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47 Cards in this Set
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LM is a 55 yr old man who presents to clinic complaining of palpitations that have been occurring for the past 2-3wks. He has a hx of hypothyroidism, HTN, COPD and atrial fibrillation. He underwent successful electrical cardioversion 3mo. ago for an episode of persistent Atrial Fibrillation and has been in normal sinus rhythm since that time. He was a 30-pack-year hx of smoking. His COPD is poorly controlled; LM has been using albuterol frequently the past few weeks.
Current meds: levothyroxine 100mcg/d ipratropium 2 puffs qid salmeterol 2 puffs bid albuterol 2 puffs q 4-6h prn hctz 25mg po qd Vital signs: B 130/80 mmHg ECG: atrial fibrillation; ventricular rate=135/min All labs are normal. His left ventricular ejection fraction is 55% Which one of the following treatment regimens is the most appropriate for managing LM's atrial fibrillation if a rate control strategy is preferred? a. Atenolol and warfarin (titrated to an INR of 2-3) b. Diltiazem and warfarin (titrated to an INR of 2-3) c. Amiodarone and warfarin (titrated to an INR of 2-3) d. No treatment is required at this time |
b. Diltiazem and warfarin (titrated to an INR of 2-3)
a) LM has uncontrolled lung disease relieved by albuteril, therefore B-blockers would not be recommended. b) Diltiazem offers rate control without risk of aggravating existing lung disease and is the best choice. Warfarin is also indicated because of his risk for stroke. c) His rate is uncontrolled at this time, however, amiodarone is not first-line therapy for rate control. d) This patient is symptomatic and is at risk for stroke while in AF, therefore he required treatment (D). |
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LM is a 55 yr old man who presents to clinic complaining of palpitations that have been occurring for the past 2-3wks. He has a hx of hypothyroidism, HTN, COPD and atrial fibrillation. He underwent successful electrical cardioversion 3mo. ago for an episode of persistent Atrial Fibrillation and has been in normal sinus rhythm since that time. He was a 30-pack-year hx of smoking. His COPD is poorly controlled; LM has been using albuterol frequently the past few weeks.
Current meds: levothyroxine 100mcg/d ipratropium 2 puffs qid salmeterol 2 puffs bid albuterol 2 puffs q 4-6h prn hctz 25mg po qd Vital signs: B 130/80 mmHg ECG: atrial fibrillation; ventricular rate=135/min All labs are normal. His left ventricular ejection fraction is 55% After 1 month, LM is still symptomatic although his ventricular rate is adequately controlled. The decision to made to attempt cardioversion again in LM and initiate chronic rhythm maintenance therapy. Which of the following medications is most appropriate at this time? a. Flecainide b. Dofetilide c. Amiodarone d. Sotalol |
a. Flecainide
a) Flecainide is the best choice for this patient given its established efficacy and low risk for organ toxicity b) & c) Amiodarone and Dofetilide are not first-line therapy for this patient since he does not have LV dysfunction |
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PB is a 51 yr old woman with a history of type 2 DM, dyslipidemia, HTN, and paroxysmal atrial fibrillation. Echocardiogram reveals left ventricular ejection fraction of 60%, no evidence of thrombus, and no left ventricular hypertrophy.
Current meds: HCTZ 25mg qd Metoprolol 50mg bid Aspirin 81mg qd Pravastatin 40mg qd Warfarin 2.5mg qd (initiated 6mo. ago) Glyburide 5mg bid Notable lab values are serum creatinine 2.0mg/dL, potassium 4.5mEq/L, INR 2.5. Her physician decides to admit her for electrical cardioversion due to increasing symptoms of fatigue and dizziness of atrial fibrillation. Following successful cardioversion, what is the most appropriate recommendation anticoagulation for PB? a. None is needed in this patient because she is in normal sinus rhythm b. Aspirin 325mg daily c. Warfarin daily for at least an additional 4 weeks following cardioversion (INR 2-3) d. Warfarin (INR 2-3) + Aspirin 325mg daily for at least an additional 4 weeks following cardioversion. |
c. Warfarin daily for at least an additional 4 weeks following cardioversion (INR 2-3)
a) Therapy is indicated for this pt. b) Aspirin is not sufficient based on her CHADS2 score c) Based on the CHADS2 score sytem, her score is >1, warfarin is indicated for this pt for an additional 4 weeks following cardioversion with a goal 2-3 d) There is no need to increase the dose of Aspirin to 325mg and add to warfarin for the purpose of preventing stroke |
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MG is a 48 yr old woman who presents to the internal medicine clinic complaining of palpitations, dizziness and fatigue, which have worsened over the past month. She has a hx of type 2 DM, dyslipidemia, prior MI (LVEF of 29%), and paroxysmal atrial fibrillation.
Current meds: Aspirin 81mg qd Lisinopril 10mg qd Metoprolol CR/XL 100mg qd Pravastatin 80mg qd Warfarin 5mg qd (initiated 6mo ago) Glyburide 5mg bid Her vital signs are B 125/75mmHg, heart rate 72/min. Labs: potassium 4.5mEq/L, serum creatinine 2.2mg/dL, INE 2.5 ECG reveals atrial fibrillation with ventricular rate of 70 bpm. MG's physician initiates amiodarone for managing MG's arrhythmia. Which of the following is most correct with respect to the monitoring parameters for MG's amiodarone therapy? a. Lung dysfunction is transient and resolves without intervention b. Liver function tests should be checked annually c. Amiodarone must be discontinued due to hypothyroidism d. GI toxicity is often dose-related and improves with dose reduction |
d. GI toxicity is often dose-related and improves with dose reduction
a) Lung dysfunction should be addressed by d/c amiodarone since this can be permanent and is not changed by dose reduction b) Liver function tests should be given every 3-6mo after baseline c) Amiodarone-induced hypothyroidism can be addressed with replacement therapy d) GI toxicity is often dose-related and improves with dose reduction |
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MG is a 48 yr old woman who presents to the internal medicine clinic complaining of palpitations, dizziness and fatigue, which have worsened over the past month. She has a hx of type 2 DM, dyslipidemia, prior MI (LVEF of 29%), and paroxysmal atrial fibrillation.
Current meds: Aspirin 81mg qd Lisinopril 10mg qd Metoprolol CR/XL 100mg qd Pravastatin 80mg qd Warfarin 5mg qd (initiated 6mo ago) Glyburide 5mg bid Her vital signs are B 125/75mmHg, heart rate 72/min. Labs: potassium 4.5mEq/L, serum creatinine 2.2mg/dL, INE 2.5 ECG reveals atrial fibrillation with ventricular rate of 70 bpm. MG's physician initiates amiodarone for managing MG's arrhythmia. MG must discontinue amiodarone due to hepatotoxicity (liver function tests >3X the upper limit of normal). Which other therapy is best for MG for managing her arrhythmia? a. Catheter ablation b. Doferilide c. Sotalol d. Propafenone |
a. Catheter ablation
a) The only option listed that is appropriate b) She should not receive doferilide due to kidney dysfunction c) & d) This patient should not receive sotalol or propafenone due to LV dysfunction. |
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RL is a 40 yr old man who recently received an implantable cardioverter defibrillator after being resuscitated from cardiac arrest due to ventricular fibrillation that was not related to acute MI. Over the past 2mo. he has received 5 shocks which he states have been extremely painful. The ICD reveals that RL is having recurrent episodes of ventricular tachycardia. He has a hx of nonischemic dilated cardiomyopathy (LVEF 25%)
Current meds: Ramipril 5mg bid Metoprolol CR/XL 150mg qd Furosemide 40mg qd Potassium Chloride 20mEq qd His vital signs are BP 108/80mmHg, HR of 62bpm. Labs are within normal range. Which of the following treatment regimens is the best for reducing the frequency of ICD shocks in RL? a. Initiate sotalol b. Initiate digoxin c. intitiate oral amiodarone d. increase metoprolol CR/XL to 200mg qd |
c. intitiate oral amiodarone
a) Sotalol, while it can be used for this purpose, is not appropriate for this patient with LV dysfunction due to risk of proarrythmia b) Digoxin is not indicated for this purpose c) Based on the lectures, amiodarone is the best option for changing the threshold of ICD firing. d) Increasing the dose of metoprolol when the HR is already 62bpm is unlikely to change the behavior of the ICD |
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FG is a 50 yr old woman who comes to the internal medicine clinic for a routine visit. Her past medical hx is significant for type 2 DM, HTN, and dyslipidemia. Currently, she is complaining of intermittent heart palpitations occurring several times daily. A 24-hour Holter monitor is placed on FG and shows 20 premature ventricular contractions per hour and 8 occurences of no-sustained ventricular tachycardia.
Meds: Lisinopril 20mg qd Glyburide 10mg bid Simvastatin 20mg qd Her BP is 125/80mmHg and HR is 75bpm What is the best recommendation to manage RT's heart palpitations? a. No treatment is necessary b. Atenolol 25mg po qd c. Amiodarone 200mg po qd d. Digoxin 0.25mg po qd |
b. Atenolol 25mg po qd
a) Since the patient is symptomatic, she should be treated. b) The best answer is Atenolol since B-blockers are considered first-line therapy for NSVT c) For the treatment of NSTV, because this patient has no indication of structural heart disease, amiodarone is not first line therapy. d) Digoxin is not indicated for this purpose |
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A 74 yr old, 68kg man is to receive Digoxin as part of therapy for CHF. His serum creatinine is 1.1mg/dL, which has been stable for several weeks. The patient is not obese (i.e. assume body weight is ideal). Calculate a maintenance dose regimen to achieve a target steady-state concentration that is in the MIDDLE of the target therapeutic range for patients with heath failure (0.5 to 1.0ng/ml) Select the exact regimen that is CLOSEST to the calculated value. Assume a tablet formulation (with the exact dose you calculate) that has a bioavailability of 75% will be used.
CLCr={ [(140-age)xbody wt] / (Scr x 72) } x 0.85 (female) Digoxin CL (L/hr) = 3.00 + (0.0546 x ClCr ml/min) MD = [(Target Css x CL x tau) / F], where tau=24hrs and F=0.75 a. 98mcg qd b. 117mcg qd c. 146mcg qd d. 156mcg qd e. 195mcg qd |
c. 146mcg qd
(look at 2008 exam #19 if you cant understand calculation) |
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Which of the following has the greatest potential to increase the INR in a patient taking warfarin?
a. Fluconazole b. Fluvoxamine c. Rifampin d. Ritonavir e. Smoking |
a. Fluconazole
S-warfarin is metabolized predominately by CYP2C9 and is the more active isomer (2-5 fold greater activity). Drugs that alter CYP2C9 are of the most concern for drug interactions. In this case, the drug would have to inhibit CYP2C9 to increase the INR (increased pharmcodynamic effect due to decreased warfarin clearance), this only answer A is correct. |
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Genetic variation in which of the following enzymes associated with warfarin dosing regimens?
a. CYP1A2 b. CYP2B6 c. CYP2C9 d. CYP2D6 e. CYP3A4 |
a. CYP2C9
S-warfarin is metabolized by CYP2C9 and carriers of one or more allelic variants (e.g. 2C9*2 or 2C9*3) typically have loswer dose requirements. |
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Which of the following statements regarding statin drugs is FALSE?
a. Itraconazole administration increases the plasma AUC of lovastatin more than pravastatin. b. Inhibition of the OATP1B1 hepatic transporter increases systemic concentrations of both atorvastatin acid and atorvastatin lactone. c. Atorvastatin, fluvastatin, and simvastatin are all lipophilic statins d. Rosuvastatin is predominantly eliminated unchanged e. The magnitude of LDL reduction observed with fluvastatin has not been shown to be dependent on genetic variation in the SLCO1B1 gene, which encodes for the OATP1B1 transporter. |
e. The magnitude of LDL reduction observed with fluvastatin has not been shown to be dependent on genetic variation in the SLCO1B1 gene, which encodes for the OATP1B1 transporter.
Answer e is false because LDL reduction has been shown to associate with the OATP1B1 haplotype (slide 86). The other statements are true. |
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KF is a 92-year-old Caucasian female with past medical history significant for
chronic obstructive pulmonary disease, hypertension, chronic heart failure (with significant left ventricular hypertrophy), and atrial fibrillation. She presents to the Emergency Room accompanied by her caretaker with a complaint of left sided weakness and slurred speech. Her home medications are as follows: diltiazem 300 mg daily, potassium chloride 40 meq twice a day, furosemide 20 mg daily, donepezil 20 mg daily, metoprolol succinate 200 mg daily, paroxetine 20 mg daily, and hydrocodone/acetaminophen as needed. Based on CHADS2 risk assessment, which of the following would be most appropriate for this patient at this time? a. Clopidigrel 75mg po daily b. Warfarin 5mg po daily c. Aspirin 325mg po daily d. Aspirin 81mg po daily |
b. Warfarin 5mg po daily
Based on CHADS2 risk assessment the patient should be on anticoagulation therapy (Warfarin). The patient has a score of 3 (age, CHF, and hypertension) which implicates warfarin therapy. Clopidigrel therapy has not been proven efficacious in stroke prevention for Atrial Fibrillation patients. |
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PY is a 71 year old man with persistent atrial fibrillation diabetes, and stable angina who was admitted for chemical cardioversion with dofetilide. His chronic medications are metoprolol, warfarin, insulin, sotalol, nitroglycerin prn, and lisinopril. After checking that his electrolytes and baseline QT-interval were within normal limits, and calculating his creatinine clearance (55 ml/min), 250 mcg of dofetilide twice daily was ordered. The patient received 2 doses and subsequently developed torsades de pointes. What treatment(s) should be provided in the care of this patient at this time?
a. Chemical cardioversion with amiodarone b. DCC c. IV magnesium d. Both B & C |
d. Both B & C
DCC and IV magnesium recommended treatments for torsades. Chemical cardioversion is not recommended for treatment of torsades. |
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JS is a 58 year old woman who presents to the ED complaining of light headedness and fluttering in her chest that began about 3 days ago. Her vitals are HR: 95 beats per minute, BP: 120/70. Past medical history is significant for Hypertension and diabetes. Her current medications include lisinopril 20 mg QD, HCTZ 25 mg QD and glyburide 10 mg QD. Her renal and Left Ventricular Ejection Fraction are normal. Based on ECG findings, she is diagnosed with acute Atrial Fibrillation. Which of the following is the best recommendation concerning cardioversion in this patient?
a. This patient should placed on warfarin for 3 weeks and then undergo direct current cardioversion. b. This patient is not a candidate for either electrical or pharmacological cardioversion. c. Initiate amiodarone 400mg TID with close ECG monitoring until cardioversion occurs. d. Administer propafenone 600 mg PO. |
a. This patient should placed on warfarin for 3 weeks and then undergo direct current cardioversion.
This patient’s AF began > 2days ago so she needs 3 weeks of anticoagulation prior to cardioversion. She is a candidate for an attempt at cardioversion b/c this is her first episode of AF. B is incorrect b/c she IS a candidate after anticoagulation. C and D are incorrect b/c she needs anticoagulation first |
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PG is a 72 year old man with a history of diabetes, hypertension, and myocardial infarction two months ago. He comes to the clinic complaining of occasional fluttering in his chest that is accompanied by dizziness. Holter monitoring reveals that he has frequent premature ventricular contractions (averaging 10 beats/hour) which are associated with his symptoms. His current medications include: aspirin 325 mg QD, lisinopril 10 mg QD, simvastatin 20 mg QD, and glyburide 5 mg BID. His vital signs include: BP 132/78 mmHg and HR 70 beats per minute. What therapy would be the best to decrease PG’s symptoms associated with these PVCs?
a. Amiodarone b. Atenolol c. Flecainide d. No drug therapy should be given at this time |
b. Atenolol
This patient has PVCs associated with symptoms. He is also post-MI. Therefore, a BB is the optimal therapy. A-amiodarone therapy is not recommended for the treatment of PVCs C-flecainide is incorrect because class IC agents are not recommended to suppress PVCs post-MI based on the results of the CAST trial. D- No drug therapy is incorrect because this patient is experiencing symptoms associated with his PVCs. In addition, he is post-MI so BB are recommended regardless if he is having PVCs or not. |
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TL is a 69 year old man who had a myocardial infarction (MI) 3 weeks ago. After his MI, his Left Ventricular Ejection Fraction was 25% and he was short of breath and could not walk a block without stopping to rest. A Holter monitor indicated that he had nonsustained ventricular tachycardia (NSVT). He is taken to the electrophysiology laboratory and is found to have non-inducible ventricular tachycardia. Which one of the following is the best treatment for TL at this time?
a. Implantable cardioverter-defibrillator (ICD) placement b. Metoprolol c. Procainamide d. Digoxin |
b. Metoprolol
The best therapy for this patient from the options above is B) Metoprolol. Β blockers and amiodarone are the recommendations for NSVT. Digoxin and Procainamide are not indicated. |
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FT is a 75-year old male admitted following an episode of syncope with a
presyncopal syndrome of seeing black spots and dizziness before passing out. Telemetry monitor reveals sustained monomorphic ventricular tachycardia for 45 seconds. His past medical history includes: Heart failure NYHA class III, Ejection Fraction=30%, myocardial infarction x 2, hypertension x 20 years, left ventricular hypertrophy, diabetes mellitus, and diabetic nephropathy. His current medications include: Lisinopril 2.5 mg qd, furosemide 20 mg BID, metoprolol 100 BID, digoxin 0.25 mg qd, glyburide 5 mg qd and aspirin 325 mg qd. BP 120/75 mmHg, HR 80 beats per minute, BUN 30 mg/dl, SCr 2.5 mg/dl. Ht: 5’6, 70 kg. Which one of the following is the best drug therapy for conversion of his sustained VT? a. Amiodarone b. Sotalol c. Dofetilide d. Procainamide |
a. Amiodarone
Sotalol and dofetilide are not used for converting VT. Also, sotalol and procainamide should not be used in patients with left ventricular dysfunction (B, C, and D incorrect). Amiodarone can be safely used in patients with LV dysfunction and renal impairment. |
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A patient taking digoxin (0.125 mg per day) for CHF is admitted to the hospital.
A serum drug concentration obtained at 1142 is 5.4 ng/ml. The patient reports that the last 0.125 mg dose was taken at approximately 0720 that day. The patient has been taking the same dose for approximately 7 weeks, has not had a change in renal function, is not exhibiting any signs of toxicity and is not taking any other medications known to interact with digoxin. Which of the following statements is TRUE? a. Digoxin doses should be held until further notice and the serum digoxin concentration should be rechecked at approximately 1900. b. The patient should be given Digibind (digoxin antibody) for acute digoxin toxicity. Concentrations should be monitored frequently. c. The digoxin concentration in this patient is not at steady-state and therefore cannot be interpreted. d. The serum drug concentration was obtained too early relative to the dose in this patient. The concentration should be rechecked no sooner that 1920 in this patient. e. The digoxin serum concentration is appropriate in this patient and no further monitoring is required. |
d. The serum drug concentration was obtained too early relative to the
dose in this patient. The concentration should be rechecked no sooner that 1920 in this patient. The concentration was obtained approximately 4.5 hours after the dose. Because digoxin exhibits multicompartment pharmacokinetics, concentrations should not be determined until at least 6-8 hours after the dose. Thus, the concentration is spuriously high due to the inappropriate sampling time. A concentration obtained at least 12 hours after the dose can be checked if necessary, |
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Which of the following statements regarding digoxin bioavailability is/are TRUE?
a. Digoxin bioavailability is decreased by co-administration of bile acid sequestrants. b. Digoxin bioavailability is increased by administration of rifampin, a P- glycoprotein inducer. c. Digoxin bioavailability is decreased in “dihydro formers” who take a broad spectrum antibiotic. d. A and C e. B and C |
a. Digoxin bioavailability is decreased by co-administration of bile acid
sequestrants. Digoxin bioavailability is decreased when bile acid sequestrants are co-administered. Digoxin F is decreased by rifampin administration due to P-gp induction and is increased in dihydro-metabolite formers when taking a broad spectrum antibiotic. |
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Which of the following statements regarding warfarin pharmacokinetics is
FALSE? a. S-warfarin is predominately metabolized by CYP2C9 and has more anticoagulant activity than R-warfarin. b. Protein binding displacement interactions are common with warfarin and frequently require a dosage adjustment. c. Fluconazole has a greater potential to affect warfarin dose requirements than fluvoxamine. d. Patients who have the CYP2C9 *3/*3 genotype typically have the smallest warfarin dose requirement. e. Warfarin clearance is typically reduced in patients who carry a variant CYP2C9 allele (e.g., *2 or *3). |
b. Protein binding displacement interactions are common with warfarin
and frequently require a dosage adjustment. Protein binding displacement interactions are common with warfarin, but are generally not clinically significant and do not require a change in dose. S-warfarin is more potent than R-warfarin and is predominately metabolized by CYP2C9. Fluconazole potently inhibits CYP2C9 and will cause a greater effect on warfarin than fluvoxamine. Carrying the *3 allele has a significant impact on warfarin dosing requirements with patients who carry the CYP2C9*3 requiring lower doses of warfarin to maintain a therapeutic INR (slide 58). Warfarin clearance is lower in patients who carry a variant allele (slide 60). |
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PT is a 55 year old man with persistent atrial fibrillation, COPD and heart failure (ejection fraction = 30%). His heart rate has been effectively controlled with extended-release metoprolol and digoxin. He is also receiving aspirin for stroke prevention and enalapril for heart failure. Today he reports that he has been having bothersome palpitations for about 3 weeks. He denies chest pain and any changes in his heart failure symptoms. HR 86/min, BP 108/77 mmHg. Which of the following is the most appropriate anticoagulation strategy for conversion to normal sinus rhythm?
a. administer heparin and immediately attempt cardioversion, start warfarin and continue for 4 weeks b. start warfarin and attempt cardioversion after 3 weeks therapeutic anticoagulation (INR 2.0-3.0), continue warfarin for 4 weeks after cardioversion c. continue aspirin and perform cardioversion in 3 weeks, start warfarin (INR 2.0-3.0) after cardioversion d. start warfarin and attempt cardioversion after 3 weeks of therapeutic anticoagulation (INR 2.0-3.0), stop warfarin after cardioversion if in normal sinus rhythm |
b. start warfarin and attempt cardioversion after 3 weeks therapeutic anticoagulation (INR 2.0-3.0), continue warfarin for 4 weeks after cardioversion
emergent cardioversion is not indicated because the patient is stable. This would be appropriate only if TEE were performed prior to cardioversion and revealed no thrombus. c is incorrect because AF has been present for more than 48 hours, so anticoagulation prior to cardioversion is necessary. d is incorrect because warfarin needs to be continued for at least 4 weeks after cardioversion. b is correct because warfarin must be administered to allow time for endogenous dissolution of any existing clot that may have developed and to prevent stroke in the post-conversion phase. |
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SW is a 79 year old woman who presents to the emergency department with complaints of frequent palpitations that have occurred for over 1 week. Her medical history is significant for stable angina, acute myocardial infarction (2003), hypertension, left ventricular hypertrophy, and diabetes. Her medications include atenolol 100 mg BID, HCTZ 25 mg daily, atorvastatin 40 mg daily, ramipril 10 mg daily, and aspirin 81 mg daily. She denies chest pain and shortness of breath. Her vital signs are stable (HR 105-120 per min and BP 105/78 mmHg). Thyroid function and electrolytes are within normal limits. Continuous ECG monitoring in the emergency department reveals that she has intermittent episodes of atrial fibrillation. The physician decides to start anticoagulation with warfarin, but is contemplating rate control vs. rhythm control.
Which of the following would be the best strategy for rate control in this patient? a. add digoxin b. change atenolol to diltiazem c. add amiodarone d. change atenolol to sotalol |
a. add digoxin
History of MI would be a compelling indication for continuing β-blocker therapy, so changing atenolol to diltiazem or sotalol would not be the most appropriate option (B and D incorrect). Additionally, while sotalol is preferable in CAD patients, this patient has LVH, which may increase risk for proarrhythmia (D incorrect). It would be most appropriate to add digoxin to see if rate control improves her symptoms. Digoxin will provide additional rate control without affecting blood pressure. Amiodarone would not be helpful for rate control in this patient primarily due to the considerable delay in the onset of these effects. Additionally, amiodarone is more appropriately used to convert the atrial fibrillation to normal sinus rhythm. |
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While you are contemplating, SW starts complaining of severe chest pain. She undergoes emergent direct current cardioversion, which is successful at restoring normal sinus rhythm (NSR). Left ventricular systolic function is preserved. Given her history of CAD, the physician wants to be more aggressive and give antiarrhythmic drugs to prevent recurrence of atrial fibrillation. Which of the following would be most appropriate for restoration of NSR in this patient?
a. flecainide b. amiodarone c. digoxin d. diltiazem |
b. amiodarone
Flecainide is contraindicated in CAD (a incorrect). Digoxin and diltiazem are both used for rate control and are most unlikely to convert this arrhythmia to NSR (c and d incorrect). Amiodarone is acceptable for patients with CAD and LVH |
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RS is a 43 year old man with paroxysmal atrial fibrillation (1 severe episode 2-4 times a year) and hypertension. He takes aspirin for stroke prevention. He does not take rate control medications because his resting heart rate is usually 80 beats/min when he is not having an episode. He was prescribed flecainide to be taken as needed for symptomatic recurrence (pill in the pocket), and now presents to the pharmacy to have it filled for the first time. You respond by doing the following:
a. filling the prescription and counseling the patient to go to the emergency room if the AF episode does not resolve b. filling the prescription and counseling the patient on the signs and symptoms of bradycardia c. calling the physician to obtain a prescription for verapamil or atenolol d. calling the physician to clarify whether the prescription should have been for propafenone |
c. calling the physician to obtain a prescription for verapamil or atenolol
The patient should be counseled on the signs and symptoms of tachycardia (b incorrect) and when to seek medical attention, but the prescription should not be filled without a prescription for an AV-node blocking drug should the patient have an episode of atrial flutter (b incorrect). Flecainide or propafenone may be used for pill in the pocket therapy (d incorrect). |
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JT is a 48 year old woman with dyslipidemia and diabetes that experienced a myocardial infarction 6 months ago with no indication of left ventricular dysfunction. Since her hospitalization, she notices that several times a day it feels like her heart “does a flip”. Holter monitoring revealed that she was having frequent premature ventricular contractions (PVCs – approximately 10/hr). Her medications include atorvastatin, aspirin, glipizide, and lisinopril. Her vital signs are HR 75/min, BP 115/84 mmHg, RR 14/min. Her laboratory tests are all within normal limits. What is the best intervention to manage JT’s symptoms?
a. carvedilol b. nitroglycerin c. amiodarone d. implantable cardiac defibrillator e. refer for electrophysiology testing |
a. carvedilol
Carvedilol is indicated in this patient given history of MI and symptomatic palpitations. Nitroglycerin is for anginal chest pain (b incorrect). Amiodarone may be considered only for persistently symptomatic patients after trial of β-blocker. ICDs are used in the management VT/VF and SCD prevention, not PVCs (d incorrect). Further diagnostic testing would be indicated if she had episodes of (NS)VT with the Holter monitor. |
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SR is a 64 year old woman with NYHA class III heart failure (ejection fraction = 35%) myocardial infarction (2005). She has inducible non-sustained ventricular tachycardia (NSVT) and an implantable cardiac defibrillator (ICD) placed roughly six months ago to prevent myocardial infarction. Since implantation, she has reported that the ICD discharged 4 times in the past 3 months, causing a great deal of discomfort. Her history is also significant for paroxysmal atrial fibrillation, hypertension, and diabetes. She is on the following medications: carvedilol, furosemide, KCl, enalapril, digoxin, spironolactone, warfarin (average INR 2.1), aspirin. She is anxious but denies worsening heart failure symptoms and chest pain. Her vital signs are stable with HR 73/min and BP 100/78 mmHg. Her labs are within normal limits.
a. d/c carvedilol and start sotalol to decrease inappropriate ICD discharge b. add amiodarone to decrease frequency of NSVT and atrial fibrillation episodes c. increase carvedilol dose to decrease ventricular response to atrial fibrillation d. nothing can be done for this patient |
b. add amiodarone to decrease frequency of NSVT and atrial fibrillation episodes
Sotalol monotherapy may be used to manage ICD discharges resulting from AF and NSVT but would not replace carvedilol in the setting of heart failure (also should be avoided in patients with heart failure due to proarrhythmia risk) (A incorrect). The patient’s rate appears to be reasonably controlled, although episodes AF with rapid ventricular response may be responsible for inappropriate ICD firings (C incorrect). Amiodarone can be used to decrease ICD firings by suppressing the ventricular arrhythmia, as well as reduce inappropriate firing that result from supraventricular arrhythmias (i.e. AF). |
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PY is a 71 year old with persistent atrial fibrillation, diabetes, and stable angina who was admitted for chemical cardioversion with dofetilide. His chronic medications are metoprolol, warfarin, insulin, ranolazine, nitroglycerin prn, and lisinopril. After checking that his electrolytes and baseline QT-interval were within normal limits, and calculating his creatinine clearance (55 ml/min), 250 mcg of dofetilide twice daily was ordered. The patient received 2 doses and subsequently developed torsades de pointes. He was treated successfully with direct current cardioversion (DCC) and magnesium. Which of the following most correctly describes this situation?
a. dofetilide should not have been used for cardioversion because it is contraindicated in patients with CrCl < 60 ml/min b. dofetilide should not have been used in someone with coronary artery disease because they are at greater risk of proarrhythmia c. ranolazine should not have been administered with dofetilide due to the risk of excessive QT-prolongation d. magnesium should be used before attempting DCC in the management of torsades de pointes |
c. ranolazine should not have been administered with dofetilide due to the risk of excessive QT-prolongation
Dofetilide is contraindicated in patients with CrCl < 20 ml/min; it is otherwise adjusted based on renal function (a incorrect). Dofetilide is acceptable to use in patients with CAD and HF (b incorrect) because it does not increase the risk of fatal arrhythmias. DCC is the first course of action in the treatment of torsades de pointes (d incorrect). |
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Digoxin therapy for congestive heart failure will be started in a 72-year-old, 52-kg woman with a stable serum creatinine concentration of 1.3 mg/dl. The patient is not obese (i.e., assume body weight is ideal). Calculate a maintenance dose regimen to achieve a target steady-state concentration of 0.80 mg/L. Select the exact regimen that is CLOSEST to the calculated value. Assume a tablet formulation that has a bioavailability of 75% will be used.
CLcr = [(140 – age) body weight] / (Scr 72)] 0.85 (female) Digoxin CL (L/hr) = 3.00 + (0.0546 CLcr ml/min) MD = [(Target Css CL ) / F] where = 24 hours and F = 0.75. a. 0.076 mg every day b. 0.091 mg every day c. 0.106 mg every day d. 0.122 mg every day e. 0.137 mg every day |
d. 0.122 mg every day
CLcr = [(140 – 72) x 52] / (1.3 x 72)] x 0.85 = 32.1 ml/min Digoxin CL = 3.0 + (0.0546 x 32.1) = 4.75 L/hr Target concentration = 0.80 ng/ml or 0.80 mcg/L MD/tau = (Css x CL) / F MD = [(Css x CL x tau)/ F], where F = 0.75 and tau= 24 hrs MD = [(Target Css x CL x tau) / F] = [(0.80 mcg/L x 4.75 L/hr x24 hr) / 0.75] = 122 mcg or 0.122 mg/day. |
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Which of the following statements regarding digoxin bioavailability is TRUE?
a. Digoxin bioavailability is increased by administration of rifampin, a P-glycoprotein inducer b. Digoxin bioavailability is increased by administration of ketoconazole, a P-glycoprotein inhibitor c. Digoxin bioavailability is higher in “dihydro formers” d. A and C e. B and C |
e. B and C
Digoxin bioavailability is increased by inhibition of the intestinal transporter P-glycoprotein (B). Digoxin bioavailability is decreased by induction of P-glycoprotein (rifampin) and is higher in “dihydro formers.” |
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Which of the following would be the MOST appropriate time to obtain a blood sample for the purposes of monitoring the serum digoxin concentration?
a. Approximately 1-2 hours after the dose b. Immediately prior to the next dose c. After the second dose of a new or revised digoxin dosing regimen d. At the time of the expected peak concentration |
b. Immediately prior to the next dose
A blood sample for measurement of the serum digoxin concentration should be obtained at least 6-8 hours after the dose and preferably, 12-24 hours after the dose (slide 11). |
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The warfarin dose requirement will probably be the smallest in which of the following patients?
a.A patient taking rifampin b. A patient who is taking fluvoxamine c. A patient who is a carrier of two CYP2C9*3 alleles d. A patient who is a carrier of two CYP2C9*1 alleles e. A patient taking a drug that displaces warfarin from protein binding sites |
c. A patient who is a carrier of two CYP2C9*3 alleles
Carrying the *3 allele has a significant impact on warfarin dosing requirements with patients who carry the CYP2C9*3 requiring lower doses of warfarin to maintain a therapeutic INR (slide 56). Rifampin is an enzyme inducer (including CYP2C9), so would likely increase the dose requirement and fluvoxamine inhibits CYP1A2, which is important in the metabolism of the less potent R-warfarin. The *1 allele is the “wild type” functional allele, which is carried by most patients (slide 57) and protein binding displacement interactions are generally not clinically significant. |
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JT is a 45 yo man with a history of hypertension and hyperthyroidism. He presents
to the ED complaining of heart palpitations and dizziness that began 6 hours prior. He has never experienced this before. An ECG reveals atrial flutter and he is successfully cardioverted using direct current cardioversion (DCC). Which of the following is the most appropriate regimen for maintenance of NSR? A. Amiodarone (Cordarone) 400 mg PO QD b. Dofetilide (Tikosyn) 500 mcg PO BID c. Sotalol (Betapace) 80 mg PO BID d. No chronic antiarrhythmic therapy is indicated as this is the patient’s first episode of A. flutter |
d. No chronic antiarrhythmic therapy is indicated as this is the patient’s first episode of A. flutter
This is the patient’s first episode of atrial flutter; chronic antiarrhythmic therapy not indicated. a, b, & c are incorrect b/c no antiarrhythmics are recommended at this time. |
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JS is a 58 yo woman who presents to the ED complaining of light headedness and fluttering in her chest that began about 3 days ago. Her vitals are HR: 130 bpm, BP: 110/60. Past medical history is significant for hypertension and diabetes. Her current medications include lisinopril (Prinivil, Zestril) 20 mg QD, HCTZ (Esidrix, others) 25 mg QD and glyburide (Diabeta) 10 mg QD. Her renal and LVEF are normal. Based on ECG findings, she is diagnosed with acute atrial fibrillation. Which one of the following is your recommendation concerning cardioversion in this patient?
a. This patient should placed on warfarin (Coumadin) for 3 weeks and then undergo direct current cardioversion. b. This patient is not a candidate for either electrical or pharmacological cardioversion. c. Initiate amiodarone (Cordarone) 400mg TID with close ECG monitoring until cardioversion occurs. d. Administer propafenone (Rhythmol) 600 mg PO. |
a. This patient should placed on warfarin (Coumadin) for 3 weeks and then undergo direct current cardioversion.
A is correct because this patient’s AF began > 2days ago so she needs 3 weeks of anticoagulation prior to cardioversion. She is a candidate for an attempt at cardioversion b/c this is her first episode of AF. b. is incorrect b/c she IS a candidate after anticoagulation c & d. are incorrect b/c she needs anticoagulation first |
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CA is a 62 yo woman who developed Atrial Fibrillation after a recent Myocardial Infarction. She has been on warfarin (Coumadin) - INR of 2.4 - and diltiazem (Cardizem, Cartia, others) 240 mg QD for the past 4 weeks and is coming in to the hospital for direct current cardioversion. She currently has a HR of 86 bpm and a BP of 116/78 mmHg. She has a past medical history of diabetes, hypertension, and myocardial infarction (6 weeks ago) with an LVEF of 40%. She has had no previous episodes of AF. Which one of the following is the best anticoagulation regimen for CA after cardioversion?
a. Warfarin (Coumadin) should be continued to maintain an INR of 2.0-3.0 for 4 weeks. b. Aspirin 325 mg/day should be continued for 4 weeks. c. No anticoagulation or antithrombotic therapy is required if normal sinus rhythm is restored. d. Warfarin (Coumadin) should be continued to maintain an INR of 1.2-1.5 indefinitely. |
a. Warfarin (Coumadin) should be continued to maintain an INR of 2.0-3.0 for 4 weeks.
a) full anticoagulation with warfarin is required for 4 weeks after cardioversion while the full atrial contraction resumes. b) is incorrect b/c the pt has risk factors (HYPERTENSION, CAD), therefore requires warfarin c) is incorrect b/c must anticoagulate even if NSR is restored until atria regain their full contraction d) No indication for goal INR of 1.2-1.5, and not given indefinitely if NSR restored. |
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MM is a 75 yo man with an ejection fraction of 30% who has experienced 4 episodes of Atrial Fibrillation (AF) in the past 3 months and develops worsening symptoms of heart failure with each episode. Due to the severity of his symptoms, he will be initiated on antiarrhythmic therapy to prevent episodes of AF. Which one of the following regimens is best for this indication AND is paired with a correct monitoring parameter?
a. Amiodarone (Cordarone) 400mg QD; monitoring parameter - serum creatinine b. Sotalol (Betapace) 80 mg BID; monitoring parameter - QT interval c. Amiodarone (Cordarone) 400 mg QD; monitoring parameter - thyroid stimulating hormone d. Sotalol (Betapace) 80 mg BID; monitoring parameter - liver function tests |
c. Amiodarone (Cordarone) 400 mg QD; monitoring parameter - thyroid stimulating hormone
c) amiodarone is first line therapy for maintenance of NSR in patients with heart failure and can cause hypo/hyper-thyroidism. TSH should be monitored at baseline and Q3-6 mos. a) is incorrect because amiodarone is incorrect b/c <1% of the dose is excreted unchanged in the urine. b) & d) are incorrect b/c amiodarone is first line therapy in a pt w/heart failure. |
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TL is a 78-year-old, 55-kg woman with congestive heart failure. Her serum creatinine is 1.6 mg/dl, which has been stable for several weeks. The patient is not obese (i.e., assume body weight is ideal). Calculate a maintenance dose regimen for digoxin (Lanoxin) to achieve a target steady-state concentration that is at the low end of the reported therapeutic range for patients with heart failure. Select the regimen that is CLOSEST to the calculated value, taking into consideration that only 0.125 mg, 0.25 mg, and 0.50 mg tablets (F=0.75) are available.
CLcr = [(140 – age) x body weight] / (Scr x 72)] x 0.85 (female) Digoxin CL (L/hr) = 3.00 + (0.0546 x CLcr ml/min) MD = [(Css x CL) / F] x tau, where tau = 24 hours. a. 0.125 mg every other day (0.0625 mg per day) b. 0.125 mg every day c. Alternate 0.125 mg and 0.250 mg daily (0.1875 mg per day) d. 0.250 mg every day |
a. 0.125 mg every other day (0.0625 mg per day)
CLcr = [(140 – 78) x 55] / (1.6 x 72) x 0.85 = 25.2 ml/min Digoxin CL = 3.0 + (0.0546 x 25.2) = 4.37 L/hr Target concentration = 0.5 ng/ml or 0.5 mcg/L MD/ = (Css x CL) / F MD = [(Css x CL) / F] x tau, where F = 0.75 and tau= 24 hrs MD = [(Css x CL) / F] x tau = [(0.5 mcg/L x 4.37 L/hr)) / 0.75] x 24 hr = 69.9 mcg or 0.0699 mg/day. So a maintenance dose of 0.125 mg every other day (0.0625 mg/day) is the closest to the calculated value. |
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Which of the following would be considered an adequate indication for digoxin (Lanoxin) therapeutic drug monitoring?
a. A patient experiencing an adverse drug reaction. b. A patient recently started on digoxin (Lanoxin) therapy. c. A patient with unstable renal function who requires a dosage adjustment. d. All of the above. e. None of the above |
d. All of the above
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Which of the following is an example of “Pharmacoenhancement” or boosting?
a. Phenytoin (Dilantin) and valproic acid (Depakote). b. Probenecid (Benemid) and penicillin. c. Ritonavir (Norvir) and lopinavir (Kaletra). d. Two of the above are examples of Pharmacoenhancement or boosting . e.All of the above are examples of Pharmacoenhancement or boosting . |
d. Two of the above are examples of Pharmacoenhancement or boosting .
Answer A is not correct, this is an example of a drug-drug interaction and not boosting. Answers B and C are both correct, probenecid and ritonavir are given for the purposes of altering the pharmacokinetics of penicillin and lopinavir, respectively. Thus, answer D is the correct choice. |
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Which of the following statements is/are TRUE?
a. Enzyme inducing drugs (e.g., rifampin [Rifadin]) generally decrease bioavailability of drugs metabolized by the affected enzyme(s). b. St. John’s wort has the greatest effect on drugs that are metabolized by CYP1A2. c. A binding or chelation interaction generally results in increased bioavailability of the affected agents. d. Two of the above are true. e. Three of the above are true. |
a. Enzyme inducing drugs (e.g., rifampin [Rifadin]) generally decrease bioavailability of drugs metabolized by the affected enzyme(s).
Answer A is correct because rifampin (Rifadin) increases metabolism, which will increase first-pass metabolism and decrease bioavailability. Answer B is not correct because St. John’s wort has the greatest effect on CYP3A-metabolized drugs. Answer C is not correct because binding or chelation interactions reduce drug absorption and therefore cause decreased bioavailability. |
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JT is a 45 yo man with a history of hypertension and hyperthyroidism. He presents
to the ED complaining of heart palpitations and dizziness that began 6 hours prior. He has never experienced this before. An ECG reveals atrial flutter and he is successfully cardioverted using direct current cardioversion (DCC). Which of the following is the most appropriate regimen for maintenance of NSR? a. Amiodarone (Cordarone) 400 mg PO QD b. Dofetilide (Tikosyn) 500 mcg PO BID c. Sotalol (Betapace) 80 mg PO BID d. No chronic antiarrhythmic therapy is indicated as this is the patient’s first episode of A. flutter |
d. No chronic antiarrhythmic therapy is indicated as this is the patient’s first
episode of A. flutter d. this is the patient’s first episode of atrial flutter; chronic antiarrhythmic therapy not indicated a, b, & c are incorrect b/c no antiarrhythmics are recommended at this time. |
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JS is a 58 yo woman who presents to the ED complaining of light headedness and fluttering in her chest that began about 3 days ago. Her vitals are HR: 130 bpm, BP: 110/60. Past medical history is significant for hypertension and diabetes. Her current medications include lisinopril (Prinivil, Zestril) 20 mg QD, HCTZ (Esidrix, others) 25 mg QD and glyburide (Diabeta) 10 mg QD. Her renal and LVEF are normal. Based on ECG findings, she is diagnosed with acute atrial fibrillation. Which one of the following is your recommendation concerning cardioversion in this patient?
a. This patient should placed on warfarin (Coumadin) for 3 weeks and then undergo direct current cardioversion. b. This patient is not a candidate for either electrical or pharmacological cardioversion. c. Initiate amiodarone (Cordarone) 400mg TID with close ECG monitoring until cardioversion occurs. d. Administer propafenone (Rhythmol) 600 mg PO. |
a. This patient should placed on warfarin (Coumadin) for 3 weeks and then undergo direct current cardioversion.
A is correct because this patient’s AF began > 2days ago so she needs 3 weeks of anticoagulation prior to cardioversion. She is a candidate for an attempt at cardioversion b/c this is her first episode of AF. b. is incorrect b/c she IS a candidate after anticoagulation c & d. are incorrect b/c she needs anticoagulation first |
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CA is a 62 yo woman who developed Atrial Fibrillation after a recent Myocardial Infarction. She has been on warfarin (Coumadin) - INR of 2.4 - and diltiazem (Cardizem, Cartia, others) 240 mg QD for the past 4 weeks and is coming in to the hospital for direct current cardioversion. She currently has a HR of 86 bpm and a BP of 116/78 mmHg. She has a past medical history of diabetes, hypertension, and myocardial infarction (6 weeks ago) with an LVEF of 40%. She has had no previous episodes of AF. Which one of the following is the best anticoagulation regimen for CA after cardioversion?
a. Warfarin (Coumadin) should be continued to maintain an INR of 2.0-3.0 for 4 weeks. b. Aspirin 325 mg/day should be continued for 4 weeks. c. No anticoagulation or antithrombotic therapy is required if normal sinus rhythm is restored. d. Warfarin (Coumadin) should be continued to maintain an INR of 1.2-1.5 indefinitely. |
a. Warfarin (Coumadin) should be continued to maintain an INR of 2.0-3.0 for 4 weeks
a. full anticoagulation with warfarin is required for 4 weeks after cardioversion while the full atrial contraction resumes. b. is incorrect b/c the pt has risk factors (HYPERTENSION, CAD), therefore requires warfarin c. is incorrect b/c must anticoagulate even if NSR is restored until atria regain their full contraction d. No indication for goal INR of 1.2-1.5, and not given indefinitely if NSR restored |
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MM is a 75 yo man with an ejection fraction of 30% who has experienced 4 episodes of Atrial Fibrillation (AF) in the past 3 months and develops worsening symptoms of heart failure with each episode. Due to the severity of his symptoms, he will be initiated on antiarrhythmic therapy to prevent episodes of AF. Which one of the following regimens is best for this indication AND is paired with a correct monitoring parameter?
a. Amiodarone (Cordarone) 400mg QD; monitoring parameter - serum creatinine b. Sotalol (Betapace) 80 mg BID; monitoring parameter - QT interval c. Amiodarone (Cordarone) 400 mg QD; monitoring parameter - thyroid stimulating hormone d. Sotalol (Betapace) 80 mg BID; monitoring parameter - liver function tests |
c. Amiodarone (Cordarone) 400 mg QD; monitoring parameter - thyroid stimulating hormone
c. amiodarone is first line therapy for maintenance of NSR in patients with heart failure and can cause hypo/hyper-thyroidism. TSH should be monitored at baseline and Q3-6 mos. a. is incorrect because amiodarone is incorrect b/c <1% of the dose is excreted unchanged in the urine. b & d. are incorrect b/c amiodarone is first line therapy in a pt w/heart failure. |
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TL is a 78-year-old, 55-kg woman with congestive heart failure. Her serum creatinine is 1.6 mg/dl, which has been stable for several weeks. The patient is not obese (i.e., assume body weight is ideal). Calculate a maintenance dose regimen for digoxin (Lanoxin) to achieve a target steady-state concentration that is at the low end of the reported therapeutic range for patients with heart failure. Select the regimen that is CLOSEST to the calculated value, taking into consideration that only 0.125 mg, 0.25 mg, and 0.50 mg tablets (F=0.75) are available.
CLcr = [(140 – age) x body weight] / (Scr x 72)] x 0.85 (female) Digoxin CL (L/hr) = 3.00 + (0.0546 x CLcr ml/min) MD = [(Css x CL) / F] x tau where tau = 24 hours. a. 0.125 mg every other day (0.0625 mg per day) b. 0.125 mg every day c. Alternate 0.125 mg and 0.250 mg daily (0.1875 mg per day) d. 0.250 mg every day |
a. 0.125 mg every other day (0.0625 mg per day)
CLcr = [(140 – 78) x 55] / (1.6 x 72) x 0.85 = 25.2 ml/min Digoxin CL = 3.0 + (0.0546 x 25.2) = 4.37 L/hr Target concentration = 0.5 ng/ml or 0.5 mcg/L MD/tau = (Css x CL) / F MD = [(Css x CL) / F] x tau where F = 0.75 and tau= 24 hrs MD = [(Css x CL) / F] x tau = [(0.5 mcg/L x 4.37 L/hr)) / 0.75] x 24 hr = 69.9 mcg or 0.0699 mg/day. So a maintenance dose of 0.125 mg every other day (0.0625 mg/day) is the closest to the calculated value. |
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Which of the following would be considered an adequate indication for digoxin (Lanoxin) therapeutic drug monitoring?
a. A patient experiencing an adverse drug reaction. b. A patient recently started on digoxin (Lanoxin) therapy. c. A patient with unstable renal function who requires a dosage adjustment. d. All of the above. e. None of the above. |
d. All of the above.
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Which of the following is an example of “Pharmacoenhancement” or boosting?
a. Phenytoin (Dilantin) and valproic acid (Depakote). b. Probenecid (Benemid) and penicillin. c. Ritonavir (Norvir) and lopinavir (Kaletra). d. Two of the above are examples of Pharmacoenhancement or boosting . e. All of the above are examples of Pharmacoenhancement or boosting |
d. Two of the above are examples of Pharmacoenhancement or boosting .
Answer A is not correct, this is an example of a drug-drug interaction and not boosting. Answers B and C are both correct, probenecid and ritonavir are given for the purposes of altering the pharmacokinetics of penicillin and lopinavir, respectively. Thus, answer D is the correct choice. |
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Which of the following statements is/are TRUE?
a. Enzyme inducing drugs (e.g., rifampin [Rifadin]) generally decrease bioavailability of drugs metabolized by the affected enzyme(s). b. St. John’s wort has the greatest effect on drugs that are metabolized by CYP1A2. c. A binding or chelation interaction generally results in increased bioavailability of the affected agents. d. Two of the above are true. e. Three of the above are true |
a. Enzyme inducing drugs (e.g., rifampin [Rifadin]) generally decrease bioavailability of drugs metabolized by the affected enzyme(s).
Answer A is correct because rifampin (Rifadin) increases metabolism, which will increase first-pass metabolism and decrease bioavailability. Answer B is not correct because St. John’s wort has the greatest effect on CYP3A-metabolized drugs. Answer C is not correct because binding or chelation interactions reduce drug absorption and therefore cause decreased bioavailability. |
