Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
58 Cards in this Set
- Front
- Back
|
Polypharmacy
(def.) |
Taking multiple drugs can cause drug-drug interactions.
- can increase or decrease the action of one or more of drugs - most dangerous when clients are getting prescriptions from different doctors & filling @ multiple pharmacies - combo of OTC w/ prescription drugs is commonplace & DANGEROUS |
|
|
Incorrect Dosing (define)
|
- Dose too small = sub-therapeutic
- Dose too large = toxic |
|
|
Tolerlance
(def) |
-occurs with the activation of excess drug-metabolizing enzymes and/or decreased sensitivity @ receptor sites.
-over time larger doses required to meet same effect. - tolerance may have cross-tolerance to drugs in the same pharmacological family |
|
|
Weight
|
- variable that affects drug action
- recommended doage based on 150lb person |
|
|
Age
|
- variable that affects drug action
- Children & Elderly usually require smaller doses - they metabolize drugs differently from young/middle aged |
|
|
Gender
|
- variable that affects drug action
- Women v Men respond differently to many drugs |
|
|
Genetic Factors
|
- variable that affects drug action
- differences among ethnic & racial groups can affect response to drugs |
|
|
Psycho-Social Factors
|
- variable that affects drug action
- A person's knowledge of a drug & attitude toward taking drug can influence the biological response. |
|
|
Time of Day
|
- variable that affects drug action
- aka Diurnal Response - drug effectiveness depends on time of day administered |
|
|
Onset of Action
|
- aspect of drug action
- the time it takes the drug to reach the min. effective concentration in the plasma after it is administered. --Pharmacological action begins here |
|
|
Peak Action
|
- aspect of drug action
- drug reaches the highest level of concentration in the plasma. - Most active at this time |
|
|
Duration of Action
|
- aspect of drug action
- length of time a drug has a pharmacological effect (not exactly from when it enters & exits body) |
|
|
Therapeutic Range
|
- aspect of drug action
- ratio between the min. effective concentration & the min. toxic concentration. - monitored for drugs w/ narrow therapeutic index via periodic blood tests |
|
|
Therapeutic Index
|
- aspect of drug action
- ratio between the effective dose & the lethal dose. Drugs with narrow Therapeutic Index maybe effective & useful BUT is DANGEROUS |
|
|
Peak & Trough Levels
|
- aspect of drug action
- measurement of blood levels of a drug. - Peak level = rate of absorption. (drawn @ time drug should reach peak) - Trough level = indicates excretion (drawn before next scheduled dose) - Usually drawn when certain IV antibiotics are administered. |
|
|
Biologic Half-Life
(t 1/2) |
-time it takes for 1/2 of drug to be eliminated from body
- if 1st half life = 4hrs, then 1/2 of drug is eliminated - 1/2 of the remaining drug is eliminated in the next 4hrs, etc - Not dose related - high degree of protein binding or sustained release, kidney and/or liver dysfunction can lengthen |
|
|
Loading Dose
|
-A large initial dose that is given quickly achieves a therapeutic blood level of a drug
|
|
|
Side Effect
|
- Uncomfortable
- drugs acting on undesired receptor site. - secondary effect - drugs sometimes used for side effect. Ex. Benadryl = drowsiness |
|
|
Adverse Reaction
|
- physiological response that is harmful to body.
- potentially life threatening |
|
|
Idiosyncratic Response
|
- unexpected response from drug
- ex. sedative might cause excitement in some ind. |
|
|
Cumulation
|
- repeated doses of drug accumulate in body. Results in greater than desired pharmacological effect
- "reservoirs" can be bone, adipose tissue, liver - also occurs when excretion of drug is decreased |
|
|
Summation
(additive effect) |
- 2 or more drugs with similar actions are given simultaneously to increase effect.
- ex. anti-hypertensives. How they vasodilate is different. |
|
|
Potentiation
(synergism) |
- 2 more drugs with dissimilar actions give simultaneously to create effect that is GREATER than sum of drugs when given independently.
- ex. morphine w/ phergen (sp) anti-histamine w/ make sleepy |
|
|
Contraindication
|
- indication that a particular drug should NOT be given
|
|
|
Teratogenic Effects
|
- causes developmental disorders in fetus.
- FDA rates drugs according to 5 pregnancy safety catagories |
|
|
Category A
|
- No evidence of risk to human fetus
|
|
|
Category B
|
- Animal studies have not demonstrated risk to fetus
|
|
|
Category C
|
- Given if potential benefits to mother outweigh pot. risks to fetus
- Animal studies have shown an adverse effect on fetus - No adequate studies in humans or no animal reproduction studies |
|
|
Category D
|
- Evidence of risk to human fetus
- Given if potential benefits to mother outweigh pot. risks to fetus |
|
|
Category X
|
- Risk to the fetus outweighs the potential benefits to mother
- Animal and/or human studies demonstrate fetal abnormalities or adverse reactions |
|
|
Pharmaceutical Phase
|
- applies only to drugs that are administered via G.I. Tract
- NO IV, topical, or sub-cu - Disintergration & Dissolve occur here |
|
|
Pharmacokinetic Phase
|
- Movement of drug
- includes Absorption, Distribution, Metabolism, & Excretion |
|
|
Absorption
|
- movement of drug from its site of entry into the body to the blood stream
|
|
|
Distribution
|
- movement of the drub from the blood stream to the interstitial space then into the cells
|
|
|
Metabolism
|
- aka biotransformation
- enzymatic transformation in the liver - makes drug water soluble |
|
|
Excretion
|
- drug eliminated via kidneys
- if lipid soluble elimination via stool |
|
|
List Variables affecting the Pharmaceutical phase
|
- Type of drug prep. ex. rapid disintergration & dissolution, sustained release, enteric coated (crushing will decrease function)
- pH of Gastric fluid. Low pH best - Incomplete Swallowing. Tabs/caps can stick to tongue. Elderly - dehydrated - must monitor Psych patients - hoard in buccal space |
|
|
Bioavailability
|
- variable affecting Absorption
- percentage of dose that reaches systemic circulation. - it's affected by route of admin, degree of 1st pass & 2nd pass effects |
|
|
Routes for Drug Administration
|
- affects Absorption
1. Intravenous (parenteral - 1-3 min onset) 2. Intramuscular (parenteral) 3. Sub-cu (parenteral - slow 30-45 min onset. Ex. insulin, heparin) 4. Intrathecal (spinal canal) 5. Intradermal (ex. TB test) 6. Oral - 30-45 min onset, most common but least bioavail 7. Sublingual - fast ex. nitroglycerin for heart pain 8. Buccal - rare 9. Transdermal - ex. nitroglycerin vasodilates - constant absorption 10. Topical 11. Rectal ex. suppositories. fast. 12. Vaginal - suppos, creams, troches 13. Inhalation - inhalers, aerosols 14. Instillation - douches, enemas, eye drops |
|
|
Degree of 1st pass effect
|
- affects Absorption
- aka Hepatic 1st pass. - decreases bioavailability - liver partially inactivates drug before blood circulation - Insulin & Heparin given via sub-cu b/c it has high 1st pass effect |
|
|
Degree of 2nd pass effect
|
- affects Absorption
- aka Drug Recycling - increase bioavailability - Live excretes unmetabolized drug into bile - Gut reabsorbs |
|
|
Number of Mucosal Microvilli in small intestine
|
- affects Absorption
- more MM, more surface area = greater absorption - Elderly - low protein diet, don't absorb as well |
|
|
Gastric Mototility
|
- affects Absorption
- rapid movement of drug from stomach to small intestine speeds absorption. Slow move = slows absorb |
|
|
Presence/Absence of Food
|
- some drugs are better absorbed in the presence of food, some in it's absence.
|
|
|
Food-Drug and Drug-Drug Interactions
|
- Milk reduces absorption of iron & tetracycline
- OJ enhances absorption of iron - Grapefruit slows metabolism of calcuim channel blockers - Foods rich in calcuim & iron decrease the absorption of most drugs - Vitamin K decreases effectiveness of Coumadin (anti-coag) - Iron & Synthroid cannot be taken at same time |
|
|
Circulation of Blood
|
- affects Distribution
- poor circulation of blood delays - P/C can be caused by shock or vasoconstriction |
|
|
Degree of Plasma Protein Binding
|
-affects Distribution
- drugs have low, med, or high degree of plasma protein binding - drug bound protein = inactive - drug unbound protein = active - Highly protein bound drugs = slow onset & long duration - Low degree of protein binding = fast onset & short duration of action - As active drug decreases in circulation, some bound drug will release to maintain balance of free drug - two high protein binding drugs = competetion of sites. Resulting in increases in amt of circulating free drug = toxicity |
|
|
Plasma Protein Levels
|
- affects Distribution
- Malnutrition lowers levels of plasma proteins - reduces bindings sites - Elderly have decreased metabolism - monitor |
|
|
Presence of Tumors or Abscesses
|
- distribution is blocked
|
|
|
Liver Disease
|
- affects Metabolism
- disease decreases ability to metabolize drugs - Elderly have slower metabolism of drugs |
|
|
Length of Half-Life
|
- affects Metabolism
- the longer the half-life, the longer it takes for the liver to metabolize the drug |
|
|
Renal Disease
|
- affects Excretion
- kidneys are partially or wholly incapable of excreting the metabolized drug. - Elderly have decreased number of functioning nephrons, result in slower excretion - patients w/ renal disease are given smaller doses, further apart in time |
|
|
Binding with Receptors
|
- affects Pharmacodynamic Phase (what drug does to body)
- greater the fit between the drug and the receptor site, the more effective the drug & fewer side effects and adverse reactions it causes - Most drugs exert effect by binding with receptors |
|
|
Inhibiting Enzymes or Hormones
|
- affects Pharmacodynamic Phase (what drug does to body)
- drugs that inhibit the action of a specific enzyme cause it to bind w/ drug instead of target cells. called Antimetabolites - ex. ACE inhibitor treat hypertension, Proscar blocks enzyme to treat Prostate cancer |
|
|
Chemical Reactions
|
- affects Pharmacodynamic Phase (what drug does to body)
- drug causes a chemical reaction by direct contact w/ body fluid. - Ex. antacids |
|
|
Increasing Osmolarity
|
- affects Pharmacodynamic Phase (what drug does to body)
- water is pulled from tissues into the bloodstream or colon thru osmosis - ex. Mannitol reduces swelling of the brain via osmosis |
|
|
Chelation
|
- affects Pharmacodynamic Phase (what drug does to body)
- Chelating agents combine with toxic metals (iron, copper, arsenic, gold, lead, zinc, mercury) to form a complex that can be excreted in urine. - ex. Calcuim EDTA or Penicillamine |
|
|
Physical Properties
|
- affects Pharmacodynamic Phase (what drug does to body)
- drug that exerts an action due to it's phyical presence - ex. Metamucil |
