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54 Cards in this Set
- Front
- Back
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What are the most common Sulfa drugs? |
Sulfisoxazole (Gantrisin), Trimethoprim/Sulfamethoxazole (Bactrim/Septra)
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What antibiotics were the first effective chemotherapeutic agents for prevention and cure of bacterial infections in humans?
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Sulfonamides |
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Which antibiotics are synthetic derivatives of p-aminobenzne sulfonamide (sulfanilamide)?
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Sulfonamides
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Which Sulfonamides are classified as "anti-infectives"?
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If they posses antibacterial activity that is antagonized by p-aminobenzoic acid or p-aminobenzoyl glutamic acid
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What is the MOA of Sulfonamides?
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Competitive antagonists of para aminobenzoic acid (PABA), this prevents normal bacterial utilization of PABA for the synethsis of folic acid
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What is the MOA of Trimethoprim?
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A potent of and selective competitive inhibitor of microbial dihydrofolate reductase, prevents formation of tetrahydrofolate from Folate
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What are the characteristics of Sulfonamides? |
Bacteriostatic, Broad Spectrum (Gram +ve and -ve), but no effect oon Anaerobes |
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What are the four pharmacological group classifications of Sulfonamides?
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1)Agents absorbed and excreted rapidly 2)Agents are absorbed poorly when given orally and are active in lumen 3)Agents that are used mainly topically 4) Long acting sulfonamides which are absorbed rapidly but excreted slowly |
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Which sulfonamides are absorbed and excreted quickly?
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Sulfisoxazole and Sulfadiazine
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Which sulfonamides are absorbed poorly when given orally and are active in the bowel lumen?
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Sulfasalazine
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Which sulfonamides are used mainly topically?
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Sulfacetamide, Mafeinde and Silver Sulfadiazine
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Which sulfonamides are long acting sulfonamides which are absorbed rapidly but excreted slowly ?
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Sulfadoxine
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"Sulfonamides should be used for prophylaxis when the risk of Malaria is low" True or False?
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False, Should be used where the risk of resistant malaria is high |
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Which are the therapeutuc uses of Sulfonamides? |
1) Urinary Tract Infections 2) Nocardiosis 3) Toxoplasmosis 4) For Prophylaxis |
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What are the three time group classifications of Sulfonamides?
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1)Short Acting (4-8hrs) 2) Intermediate Acting (8-12hrs) 3) Long Acting (7 days) |
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What are the therapeutic uses of Sulfonamides/Trimethoprim?
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1) Urinary Tract Infection 2) Respiratory Tract Infections 3) Pulmonary Infections 4) Gastrointestinal Infections |
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"Trimethoprim on its own is as effective as Trimethoprim/Sulfamethoxazole combination for the treatment of respiratory tract or urinary tract infections" True or False
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TRUE |
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How common is resistance to Sulfonamide/Trimethoprim?
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Drug resistance is a problem
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"The combination of Sulfamethoxazole/Trimethoprim is equally as effective the individual components in stopping bacterial growth" True or False
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False, It is much more effective
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What are the pharmacokinetics of Sulfonamides?
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Absorbed rapidly from GI tract, 70-100% absorbed, peak plasma in 2-6hrs. Passes readily through the placenta and reaches fetal circulation and conc accumulates to toxic levels. Sulfonamides are eliminated from the body partly unchanged partly metabolic products
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"Sulfonamides can be detected in the urine within 30 minutes of ingestion" True or False?
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TRUE
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What is the major site of absorption for Sulfonamides?
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Small Intestine {but some of the drug is also absorbed from the stomach}
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"Excretions of Sulfa is lower at night time than daytime" True or False?
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False, Excretion is higher at night
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What is Crystaluria?
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In acidic urine, the older sulfonamides are insoluble and may precepitate forming crystalline deposits that can cause obstructions
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What are the adverse reactions of Sulfonamides? |
Most Common: Fever, skin rashes, nausea, vomitting and diarrhea. Disturbances in the urinary tract. Disoerders of Hematopoeitc system. |
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What causes the resistance of Sulfonamides?
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Due to mutations that result in overproduction of PABA of a folic acid synthesizing enzymes which has low affinity for sulfonamides. Dihydropteroate synthase with low sulfonamide affinity is transmissblle and disseminated rapidly. |
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What are adverse effects of Sulfonamides/Trimethoprim?
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Crystalluria, Hypersensitivity, Kernicterus
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What is "Kernicterus"?
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A condition which occurs in newborns, where sulfa drugs displace billiruben from binding sites on serum albumin and the billiruben is then free to pass into the CNS because the BBB is not fully developed
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What are the two sites of bile deposit in Kernictus?
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Two places in the brain: 1)Basal Ganglia 2)Subthalamic Region |
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"Sulfa drugs are contraindicated in newborns and infants less than 2 months of age as well as in pregnant women" True or False?
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TRUE
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What are the most common Quinolones?
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Nalidixic Acid, Ciprofloxacin
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"Quinolones are antimicrobials effective in treatment of selected community acquired and nosomical infection" True or False?
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TRUE
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How are Quinolones made into Broad Spectrum?
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By attaching a Fluro group
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What are the characterisitics of Quinolones?
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Active against Gram positive cocci. |
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What are the characteristics of first generation Quinolones?
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Moderate gram(-ve) activity and minimal systemic distribution
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What are the characteristics of second generation Quinolones?
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Expanded gram (-ve) activity and atypical pathogens but limited gram (+ve) activity
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What are the characteristics of third generation Quinolones?
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Retains the Expanded gram(-ve) and atypical pathogens of second generation, but improved gram (+ve) coverage |
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What are the characteristics of fourth generation Quinolones?
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Improved gram (+ve) coverage and maintains gram (-ve) coverage and gains anaerobic coverage
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Which Quinolone is the most active against Pseudomonas aeuginosa?
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Ciprofloxacin
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What is the MOA of Quinolones?
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Quinones rapidly inhibit DNA synthesis by promoting cleavage of bacterial DNA, the targets are DNA gyrase and Type IV topiosomerase which results in rapid bacterial death |
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What is the other name for DNA gyrase?
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Type 2 Topiosomerase
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Which type of Bacteria correlates with which Quinolone Targets?
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Gram(-ve) bacteria correlates with inhibition of DNA gyrase. Gram (+ve) bacteria corresponds with inhibition of DNA topoisomerase IV
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What are the theraputic uses of Quinolones?
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1) Prostatitis 2) Genitourinary Infections 3) Respiratory Diseases 4) Skin and Soft tissue infections 5) Gastroentertitis 6) Sexually transmitted diseases |
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"Quinolones are very synergistic with many antibiotics" True or False?
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False, they are not predictably synergisitc
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"Ciprofloxacin and Rifampin appear to be antagonistic when used against Staph Aureus" True or False?
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True |
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What are the pharmacokinetics of Quinolones?
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Well absorbed following oral administration, food does not impair absorption of most Quinolones, Quinolones chelate with cations. Widely distibuted throughout body with higher tissue penetration then tissue concentration. They are eliminated by renal and non-renal routes. |
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"IV serum drug levels of Quinolones are comparable to oral administration" True or False?
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TRUE |
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"Quinolones intracelluar concentration is exceptional in _______ and ________"
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Neutrophils and Macrophages
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"Quinolones are eliminated mostly by Hepatic pathways" True or False?
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False, They are mostly excreted renally |
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Which Quinolones are the exception to the rule and are excreted hepatically? |
1)Sparfloxacin (Zagam) 2)Moxifloxacin (Avelox) 3)Trovafloxacin (Trovan) |
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How common is Resistance to Quinolones?
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Common for Nalidixic acid and developing for Ciprofloxacin |
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How does resistance develop to Quinolones?
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1) Caused by mutations in the genes of the target enzymes (DNA Gyrase and DNA Topoisomerase IV). 2) Also porin and efflux pumps mutations. |
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What are adverse effects of Quinolones?
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GI: nausea, vomitting, diarrhea and abdominal pain. CNS: Headaches, dizziness, drowsiness, confusion, insomnia, fatigue, depression, somnolence, seizures, vertigo, restlessness and tremors. Derm: Rash, pruritis, photosensitivity reactions |
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What are the drug interactions of Quinolones?
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1) May increase risk of CNS stimulations and convulsions if used concomitantly with NSAIDs 2) May lead to hypoglycemia an/or hyperglycemia if used concomittanly with antidiabetic agents 3) Probenecids increase the halflife of the drug by competing with renal clearance 4) H2RAs decreases absorption of Quinolones |
