Pharmacology Mnemonics - Flash Cards

Name: Iodine

Class:

Mechanism: 80% contained in thyroglobulin.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility:

Special Features: Deficiency ® endemic goiter. Excess (>20 x RDA) ® blocked organification of iodine ® myxedema.

Name: Vitamin B₁₂ (Cyanocobalamin)

Class:

Mechanism: Necessary for folate Metabolismolism and DNA synth. Maintains myelinization of spinal cord tracts.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility:

Special Features: Vegan diet ® deficiency ® megaloblastic pernicious anemia and degeneration of posterolateral spinal cord tracts. If patient is deficient in B₁₂ and folate, replace B_12­ first to avoid irreversible neuro damage. Liver damage ® ­ need.

Name: Biotin

Class:

Mechanism: Incorporated in coenzyme A.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility:

Special Features: Some antibiotics kill gut microbes that synthesize biotin.

Name: Vitamin B₃ (Niacin)

Class:

Mechanism: Incorporated into NAD and NADP.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility:

Special Features: Deficiency ® pellagra (dementia, dermatitis, diarrhea). Penicillamine, hydralazine, and isoniazid complex w/B₆ ® ¯ B₆. B₆ is a cofactor of tryptophan ® nicotinic acid conversion. Results in ¯ B₃.

Name: Vitamin B₆ (Pyridoxine)

Class:

Mechanism: Derivatives serve as coenzymes in many intermed. rxns.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Megadose—severe (often irreversible) sensory neuropathy

Utility:

Special Features: Deficiency ® cheilosis, glossitis, dermatitis, peripheral neuropathy. Liver damage ® ­ need. Penicillamine, hydralazine, and isoniazid complex w/B₆ ® ¯ B₆. B₆ is a cofactor of tryptophan ® nicotinic acid conversion. Results in ¯ B₃. Pregnancy ® ­ B₆ demand.

Name: Vitamin B₁ (Thiamine)

Class:

Mechanism: Coenzyme in decarboxylation rxns. Facilitates conduction of impulses in peripheral nerves.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility:

Special Features: Deficiency ® dry & wet beriberi, Wernicke-Korsakoff’s synd. RDA directly proportional to caloric intake. Deficiency common in alcoholics.

Name: Vitamin B₂ (Riboflavin)

Class:

Mechanism: Converted to coenzymes FMN and FAD.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility:

Special Features: Deficiency ® ariboflavinosis, cheilosis, stomatitis, glossitis, dermatitis, corneal vascularization.

Name: Vitamin K

Class:

Mechanism: Cofactor in hepatic carboxylation of procoagulants—factors II, VII, IX, and X.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility: Antagonize coumarin anticoagulation (min. dose = 60-100 x RDA). Infants given injxn (infant GI tract lacks microbes that produce vitamin K).

Special Features: Deficiency ® bleeding diathesis. Some antibiotics kill gut microbes that synthesize vitamin K. Bishydroxycoumarin antagonizes effects of vitamin K. Prolonged use of large dose salicylates block vitamin K actions in prothrombin synth. ® hypoprothrombinemia.

Name: Vitamin Vitamin

Class:

Mechanism: Fat soluble antioxidant. Scavenges free radicals. Conc. in adipose tissue.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Diarrhea, headache.

Utility: Large doses may reduce rate of buildup of atherosclerotic plaques in coronary arteries and protect against stroke and heart disease.

Special Features: RDA directly proportional to intake of polyunsaturated fatty acids. Deficiency ® spinocerebellar degeneration.

Name: Ofloxacin (Floxin)

Class: Fluorinated quinolone

Mechanism: Inhib bact. DNA gyrase (topoisomerase II). Bactericidal.

Absorption: Oral admin.

Distrib.: Good tissue penetration.

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Usu. not severe. GI, CNS. Not for pregnant or nursing women or prepubertal children.

Utility: UTIs due to Enterobacteriaceae, Enteroccus, Staph, Pseudomonas. Infectious diarrhea.

Special Features: Broader spectrum than nonfluorinated quinolones. For diarrhea, treat until symptoms resolve, or no longer than 3 days.

Name: Ciprofloxacin (Cipro)

Class: Fluorinated quinolone

Mechanism: Inhib bact. DNA gyrase (topoisomerase II). Bactericidal.

Absorption: Rapid absorption after oral admin.

Distrib.: Good tissue penetration. Poor CSF.

Metabolism.: Partial hepatic Metabolism.

Excretion, t½: Glomerular filtration, secretion. Also feces, bile, sputum. 4 hr.

Toxicity/S.E.s: Usu. not severe. GI, CNS, arthropathy. Not for pregnant or nursing women or prepubertal children.

Utility: Upper and lower UTIs, DOC for Pseudomonas UTIs. Active against aerobic gram- bacilli, H. influenzae, Neisseria. Good for several causes of infectious diarrhea, osteomyelitis, and patients w/CF.

Special Features: Broader spectrum than nonfluorinated quinolones. For diarrhea, treat until symptoms resolve, or no longer than 3 days.

Name: Norfloxacin (Noroxin)

Class: Fluorinated quinolone

Mechanism: Inhib bact. DNA gyrase (topoisomerase II). Bactericidal.

Absorption: Oral admin.

Distrib.: Good tissue penetration.

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Usu. not severe. GI, CNS. Not for pregnant or nursing women or prepubertal children.

Utility: UTIs due to Enterobacteriaceae, Enteroccus, Staph, Pseudomonas. Infectious diarrhea.

Special Features: Broader spectrum than nonfluorinated quinolones. For diarrhea, treat until symptoms resolve, or no longer than 3 days.

Name: Folic Acid

Class:

Mechanism: Essential for transfer and utilization of 1-carbon units in DNA synth.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility: Recommended for all premenopausal women at dose of 2 x RDA ® reduced risk of neural tube defects. Lowers homocysteine, reduces risk of heart disease. May lower risk of cervical cancer. Treat folate-responsive schizophrenia (50-150 x RDA ® ¯ buildup of urinary homocysteine ® ¯ psychiatric symptoms).

Special Features: Deficiency ® megaloblastic anemia. Alcoholism ® ¯ folate absorption. Pregnancy ® ­ folate demand.

Name: Vitamin A

Class:

Mechanism: Component of visual pigment. Maintains specialized epithelia and resistance to infxn.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Megadose—teratogenic (face, head, brain, heart), thickening of the leg bones, ­ intracranial pressure.

Utility:

Special Features: Deficiency ® night blindness, xerophthalmia, blindness, squamous metaplasia, infxn vulnerability (esp. measles). Liver damage ® ­ need.

Name: Vitamin C

Class:

Mechanism:

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Diarrhea. Megadose—diarrhea, kidney stones, precipitation of sickle cell crisis, transient infertility, altered renal secretion of weak acids and bases.

Utility: Large doses may reduce rate of buildup of atherosclerotic plaques in coronary arteries and protect against stroke and heart disease.

Special Features: TB pts. probably need 2x normal amount of vitamin C.

Name: Vitamin D

Class:

Mechanism: Facilitates intest. absorption of Ca²⁺ and PO₄^3-, and mineralization of bone.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Megadose—hypercalcemia.

Utility:

Special Features: Quasi-vitamin—synthesized in humans. RDA inversely proportional to amount of UV light exposure. Deficiency ® rickets (kids), osteomalacia (adults).

Name: Trimethoprim-Sulfamethoxazole (Bactrim, Septra)

Class: Antimicrobial

Mechanism: Acts on two sequential steps in synth of folic acid. PABA competitive inhib, dihydrofolate reductase inhib. Bacteriostatic.

Absorption: Oral, IV

Distrib.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Megaloblastic anemia, leukopenia, granulocytopenia (prevented by admin. of folic acid)

Utility: Uncomp. UTIs, otitis media, acute exacerbations of chronic bronchitis, various pneumonias. DOC for Travelers’ diarrhea (esp. in kids), P. carinii pneumonia, Shigella enteritis, systemic Salmonella infects, prostatitis.

Special Features: Trimethoprim = highly selective inhib. of bacterial dihydrofolate reductase. For diarrhea, treat until symptoms resolve, or no longer than 3 days.

Name: Difenoxin-Atropine (Motofen)

Class: Opioid (Antidiarrheal)

Mechanism: Increased gastric tone ® delayed gastric emptying. ­ tone and ¯ propulsive peristaltic waves in large intest. ® ¯ gut motility. Effects due to inhib. of ACh release by neurons in the intest. wall. Naloxone sensitive.

Absorption: Oral

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Recommended dose ® dizziness, drowsiness, mild euphoria. Excessive doses ® pronounced euphoria, potentially serious respiratory depression (may not be evident until 12-30 hr later). ¯ peristalsis ® ¯ evacuation of bacteria and toxins. Use w/great caution in kids. Potentiates effects of barbiturate, tranquilizers, alcohol, other narcotics. Hypertensive crisis w/MAOI.

Utility: Antidiarrheal.

Special Features: Difenoxin has 5x potency of diphenoxylate. Atropine included primarily to prevent drug abuse. Kids esp. sensitive to atropine toxicity.

Name: Paregoric

Class: Opioid (Antidiarrheal)

Mechanism: Preparation of oral morphine, anise oil, benzoic acid, camphor, diluted alcohol, and glycerin. Increased gastric tone ® delayed gastric emptying. ­ tone and ¯ propulsive peristaltic waves in large intest. ® ¯ gut motility. Effects due to inhib. of ACh release by neurons in the intest. wall. Naloxone sensitive.

Absorption: Oral

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s:

Utility: Antidiarrheal.

Special Features:

Name: Loperamide (Imodium)

Class: Opioid (Antidiarrheal) (OTC)

Mechanism: Increased gastric tone ® delayed gastric emptying. Increase tone and decreased propulsive peristaltic waves in large intest. ® decreased gut motility. Effects due to inhib. of ACh release by neurons in the intest. wall. Naloxone sensitive. Anti-secretory effect (non-naloxone sensitive).

Absorption: Oral

Dist.: 90% ® GI tract and liver. Very little CNS.

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: ¯ peristalsis ® ¯ evacuation of bacteria and toxins.

Utility: Antidiarrheal. Traveler’s Diarrhea.

Special Features: No abuse liability. Preferred anti-diarrheal of the opioids. Less potential for analgesia, respiratory depression, and addiction than other opioids. Much safer than other opioids. Longer lasting effects than diphenoxylate.

Name: Diphenoxylate-Atropine (Lomotil)

Class: Opioid (Antidiarrheal)

Mechanism: Increased gastric tone ® delayed gastric emptying. ­ tone and ¯ propulsive peristaltic waves in large intest. ® ¯ gut motility. Effects due to inhib. of ACh release by neurons in the intest. wall. Naloxone sensitive.

Absorption: Oral

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Recommended dose ® dizziness, drowsiness, mild euphoria. Excessive doses ® pronounced euphoria, potentially serious respiratory depression (may not be evident until 12-30 hr later). ¯ peristalsis ® ¯ evacuation of bacteria and toxins. Use w/great caution in kids. Potentiates effects of barbiturate, tranquilizers, alcohol, other narcotics. Hypertensive crisis w/MAOI.

Utility: Antidiarrheal.

Special Features: Atropine included primarily to prevent drug abuse. Kids esp. sensitive to atropine toxicity.

Name: Kaolin-Pectin (Kaopectate)

Class: Antidiarrheal Drug (Hydrophilic Agent/Absorbent)

Mechanism: Kaolin + pectin. Absorb water, bacteria, virus, toxins, bile acids. Decrease fluidity of formed stool.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: May increase water and electrolyte loss. May absorb nutrients, folate, drugs.

Utility: Treat diarrhea.

Special Features: Not terribly effective.

Name: Docusates (Colace, Doxinate)

Class: Laxative

Mechanism: Anionic surfactant. Becomes emulsified w/stool ® softer feces, easier passage. Requires 1-3 days for action.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: May increase intestinal absorption of other drugs. Don’t use w/lubricant oils. May be mutagenic to cultured liver cells.

Utility: Laxative. Use limited to keeping stool soft.

Special Features: Only a minimal laxative effect at recommended dosage.

Name: Lubricant Oils (mineral oil, olive oil, etc.)

Class: Laxative

Mechanism: Coat stomach contents, change consistency of stool, reduce water absorption.

Absorption: Oral, enema.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Oil absorption ® foreign body rxn. Possible lipid pneumonia. Decreased absorption of fat-soluble nutrients.

Utility: Laxative. Mineral oil enemas relieve fecal impaction.

Special Features: Seldom given orally, as better agents are available.

Name: Lactulose (Constilac, Cephulac)

Class: Laxative (Osmotic Laxative)

Mechanism: Galactose-fructose disaccharide ® osmotic effect in small intest. In colon, Metabolism. by bacteria to lactic, formic, and acetic acids ® osmotic effect.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Not for use in pts on low galactose diets. Antacids can block fecal acidification (® ¯ effect on portal-systemic encephalopathy). Neomycin interferes w/lactulose action.

Utility: 1° use = symptomatic treatment of portal-systemic encephalopathy assoc. w/chronic liver disease. Acidified feces ® ­ NH₄⁺ excretion. Routine purgation.

Special Features: May be preferred for elderly patients for routine purgation, but expensive.

Name: Castor Oil

Class: Laxative (Contact Cathartic)

Mechanism: Broken down in small intest. to ricinoleic acid (anionic surfactant) ® gut irritation ® ­ peristalsis. ¯ small intest. absorption of electrolytes and water, ­ speed of transit through GI tract. Effective in as little as 2 hr.

Absorption:

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Must not be used chronically ® ¯ nutrient absorption. Violent uterine and abdominal cramping.

Utility: Laxative

Name: Anthraquinones (senna, cascara, danthron, aloe)

Class: Laxative (Contact Cathartic) (Anthraquinone Cathartic)

Mechanism: Emodin, an anthraquinone, stimulates peristalsis in the colon. Effects take > 6 hr. to develop.

Absorption:

Dist.: Breast milk.

Metabolism.:

Excretion, t½: Partial kidney excretion (may color urine).

Toxicity/S.E.s: Excessive catharsis. Colored urine. Not to be used by nursing mothers.

Utility: Laxative

Special Features: Activated by intestinal microflora. More complete evacuation than diphenylmethanes. Contact cathartics are most commonly involved in prolonged cathartic abuse. Should never be used > 1 wk of regular therapy. Not recommended for initial therapy.

Name: Bisacodyl Tannex (Clysodrast)

Class: Laxative (Contact Cathartic) (Diphenylmethane Cathartic)

Mechanism: Act on colon ® ­ peristalsis.

Absorption: Enema.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Fluid and electrolyte depletion, abdominal cramping, Metabolismolic acidosis or alkalosis, hypocalcemia, tetany. Tannic acid in large amounts is hepatotoxic. Use caution w/multiple enemas. Don’t use in pts. w/colonic ulcers or in kids < style=""> Don’t use > 7.5 g at a time or > 10 g over 72 hr.

Utility: Preparation of colon for surgery or X-ray.

Special Features: Indiv. effective doses vary 4-8x. Acid/base indicator ® pink/red urine.

Name: Bisacodyl (Dulcolax)

Class: Laxative (Contact Cathartic) (Diphenylmethane Cathartic)

Mechanism: Act on colon ® ­ peristalsis. Effects take at least 6 hr. to manifest.

Absorption: Oral ® 5% absorption. Enema, suppositories (can be irritating).

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Fluid and electrolyte depletion, abdominal cramping, Metabolismolic acidosis or alkalosis, hypocalcemia, tetany. Potential for atonic colon w/prolonged use.

Utility: Preparation of colon for surgery or X-ray.

Special Features: Most useful contact cathartic. Indiv. effective doses vary 4-8x. Acid/base indicator ® pink/red urine. Contact cathartics are most commonly involved in prolonged cathartic abuse. Should never be used > 1 wk of regular therapy. Not recommended for initial therapy.

Name: Phenolphthalein (Ex-Lax)

Class: Laxative (Contact Cathartic) (Diphenylmethane Cathartic)

Mechanism: Act on colon ® ­ peristalsis. Effects take at least 6 hr. to manifest.

Absorption: Oral ® 15% absorption

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Fluid and electrolyte depletion, abdominal cramping, ashes, osteomalacia. Potential for atonic colon w/prolonged use.

Utility: Laxative.

Special Features: Indiv. effective doses vary 4-8x. Acid/base indicator ® pink/red urine. Not effective in pts. who lack bile. Contact cathartics are most commonly involved in prolonged cathartic abuse. Should never be used > 1 wk of regular therapy. Not recommended for initial therapy.

Name: Sodium Phosphate

Class: Laxative (Saline Cathartic)

Mechanism: Nonabsorbable ions ® ­ osmotic pressure in bowel ® watery stools in 1-3 hr.

Absorption: Not much.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Large amount of Na⁺ (prob. for pts. on low Na⁺ diets). Potential problem of dehydration.

Utility: Acute evacuation of bowel in preparation for endoscopic exam. Elim. of drugs/toxins for suspected drug/food poisoning.

Special Features:

Name: Magnesium Citrate

Class: Laxative (Saline Cathartic)

Mechanism: Nonabsorbable ions® ­ osmotic pressure in bowel ® watery stools in 1-3 hr.

Absorption: Not much.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Toxic levels of Mg²⁺ may accumulate in infants, old folk, and pts. w/impaired renal fxn. Large amount of Na⁺ (prob. for pts. on low Na⁺ diets). Potential problem of dehydration.

Utility: Acute evacuation of bowel in preparation for endoscopic exam. Elim. of drugs/toxins for suspected drug/food poisoning.

Special Features:

Name: Magnesium Hydroxide

Class: Laxative (Saline Cathartic)

Mechanism: Nonabsorbable ions ® ­ osmotic pressure in bowel ® watery stools in 1-3 hr.

Absorption: Not much.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Toxic levels of Mg²⁺ may accumulate in infants, old folk, and pts. w/impaired renal fxn. Large amount of Na⁺ (prob. for pts. on low Na⁺ diets). Potential problem of dehydration.

Utility: Acute evacuation of bowel in preparation for endoscopic exam. Elim. of drugs/toxins for suspected drug/food poisoning.

Special Features:

Name: Polycarbophil

Class: Laxative (Bulk-Forming Agent)

Mechanism: Absorbs and retains water, increases fecal volume ® ­ rate of transit.

Absorption: Not absorbed.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Can bind other drugs ® reduced absorption. Admin. > 1 hr before or after other medication.

Utility: Laxative. Esp. useful in pts. w/alternating constipation and diarrhea (e.g., irritable bowel synd) ® ¯ fluidity of liquid stools and softening of hard stools. Also useful for pts who are on low residue diets; are postpartum; are elderly; or have diverticular disease, spastic colon, or hemorrhoids.

Special Features: Inert, hydrophilic. Introduce gradually to avoid GI impaction. Gentle agent. Requires 1/2-3 days for effect.

Name: Magnesium Sulfate

Class: Laxative (Saline Cathartic)

Mechanism: Nonabsorbable ions® ­ osmotic pressure in bowel ® watery stools in 1-3 hr.

Absorption: Not much.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Toxic levels of Mg²⁺ may accumulate in infants, old folk, and pts. w/impaired renal fxn. Large amount of Na⁺ (prob. for pts. on low Na⁺ diets). Potential problem of dehydration.

Utility: Acute evacuation of bowel in preparation for endoscopic exam. Elim. of drugs/toxins for suspected drug/food poisoning.

Special Features:

Name: Psyllium (Metamucil)

Class: Laxative (Bulk-Forming Agent)

Mechanism: Absorbs and retains water, increases fecal volume ® ­ rate of transit.

Absorption: Not absorbed.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Can bind other drugs ® reduced absorption. Admin. > 1 hr before or after other medication.

Utility: Laxative. Esp. useful in pts. w/alternating constipation and diarrhea (e.g., irritable bowel synd) ® ¯ fluidity of liquid stools and softening of hard stools. Also useful for pts who are on low residue diets; are postpartum; are elderly; or have diverticular disease, spastic colon, or hemorrhoids.

Special Features: Inert, hydrophilic. Introduce gradually to avoid GI impaction. Gentle agent. Requires 1/2-3 days for effect.

Name: Methylcellulose

Class: Laxative (Bulk-Forming Agent)

Mechanism: Absorbs and retains water, increases fecal volume ® ­ rate of transit.

Absorption: Not absorbed.

Dist.:

Metabolism.:

Excretion, t½:

Toxicity/S.E.s: Can bind other drugs ® reduced absorption. Admin. > 1 hr before or after other medication.

Utility: Laxative. Esp. useful in pts. w/alternating constipation and diarrhea (e.g., irritable bowel synd) ® ¯ fluidity of liquid stools and softening of hard stools. Also useful for pts who are on low residue diets; are postpartum; are elderly; or have diverticular disease, spastic colon, or hemorrhoids.

Special Features: Inert, hydrophilic. Introduce gradually to avoid GI impaction. Gentle agent. Requires 1/2-3 days for effect.

Name: Tetracycline (Achromycin V)

Class: Tetracycline

Mechanism: Active uptake into bacteria ®inhib protein synth by binding to 30S ribosome. Bacteriostatic

Absorption: Oral adequate, but incomplete. Impaired by divalent cations. IM painful. IV may cause thrombophlebitis. Never intrathecal.

Distrib.: Good CSF. Conc. in liver ® enterohepatic circ. Penetrates most tissues and fluids. Crosses placenta.

Metabolism.:

Excretion, t½: filtration (1°), bile

Toxicity/S.E.s: GI — burning, discomfort, nausea, vomiting; superinfection — due to broad spectrum, candida albicans (1°), staph enterocolitis, pseudomemb. colitis; hepatotoxicity (esp. in pregnancy); renal toxicity; Fanconi synd.; perm. brown discoloration of teeth; slowing of bone growth; phototoxicity; thrombophlebitis; hematopoetic changes; rare hypersens. rxns.

Utility: gram - cocci, gram - bacilli, acid fast bacilli, chlamydiae, mycoplasma, rickettsia, spirochetes. No effect on viruses or fungi. Also used for acne, prophylaxis for Travelers’ diarrhea. H. pylori (PUD).

Special Features: Broad spectrum. Decreased effect of oral contraceptives.

Name: Amoxicillin (Amoxil)

Class: Penicillin (Aminopenicillin)

Mechanism: Binds to PBPs, blocks activity of transpeptidases in terminal stages of cell wall formation. Bactericidal.

Absorption: Acid stable. Good oral (better than ampicillin).

Distrib.: Widely distributed, little CSF unless meninges inflamed.

Metabolism.:

Excretion, t½: Rapidly elim. by kidneys (probenecid blocks excretion), small amt. in bile.

Toxicity/S.E.s: diarrhea (less than ampicillin), hypersensitivity (1-10%), superinfection.

Utility: More effective against gram -s (esp. Proteus, H. influenzae, E. coli, P. mirabilis). Less active than Pen. G against gram+ cocci. H. pylori (PUD).

Special Features: Broad spectrum.