Pharmacology GI Cards PDF

Name: Ranitidine (Zantac) Class: H2 Receptor Antagonist...

Name: Ranitidine (Zantac) Class: H2 Receptor Antagonist Mech.: Competitive inhib. of the histamine H2 receptor, but not of the H1 receptor → inhib. of fasting and stim. acid secretion. No disruption of circadian rhythm of acid secretion. Inhib. of 80-90% of gastrin and vagal-stim. acid secretion. Pharmacology Absorption: Oral → rapid, good absorption. Single nighttime dose. Dist.: Metab.: Partial hepatic metab. Excretion, t_: Excreted intact in urine. 1.5-3 hr. GI – Cards Toxicity/S.E.s: Uncommon. Diarrhea, headaches, myalgias, skin rashes. Inhib. cyt. P-450 (less than cimetidine) → dose adjustment with phenytoin, warfarin, & theophylline. Occasional cardiac arrhythmias. Utility: PUD, Zollinger-Ellison synd., acute stress ulcers, GERD Special Features: Potency—famotidine > ranitidine/nizatidine > cimetidine. Tachyphylaxis—50% less effective after 6 months. Rebound hypersecretion 2° to receptor upregulation and inhib. of ATPase recycling. Name: Cimetidine (Tagamet) Name: Nizatidine (Axid) Class: H2 Receptor Antagonist Class: H2 Receptor Antagonist Mech.: Competitive inhib. of the histamine H2 receptor, but not of the H1 Mech.: Competitive inhib. of the histamine H2 receptor, but not of the H1 receptor → inhib. of fasting and stim. acid secretion. No disruption of receptor → inhib. of fasting and stim. acid secretion. No disruption of circadian rhythm of acid secretion. Inhib. of 80-90% of gastrin and circadian rhythm of acid secretion. Inhib. of 80-90% of gastrin and vagal-stim. acid secretion. vagal-stim. acid secretion. Absorption: Oral → rapid, good absorption. Single nighttime dose. Absorption: Oral → rapid, good absorption. Single nighttime dose. Dist.: Dist.: Metab.: Partial hepatic metab. Metab.: Partial hepatic metab. Excretion, t_: Excreted intact in urine. 1.5-3 hr. Excretion, t_: Excreted intact in urine. 1.5-3 hr. Toxicity/S.E.s: Uncommon. Diarrhea, headaches, myalgias, skin rashes. Toxicity/S.E.s: Uncommon. Diarrhea, headaches, myalgias, skin rashes. Large doses over prolonged periods assoc. w/impotence & Occasional cardiac arrhythmias. gynecomastia. Inhib. cyt. P-450 → dose adjustment with phenytoin, Utility: PUD, Zollinger-Ellison synd., acute stress ulcers, GERD warfarin, & theophylline. Occasional cardiac arrhythmias. Special Features: Potency—famotidine > ranitidine/nizatidine > cimetidine. Utility: PUD, Zollinger-Ellison synd., acute stress ulcers, GERD Tachyphylaxis—50% less effective after 6 months. Rebound Special Features: Potency—famotidine > ranitidine/nizatidine > cimetidine. hypersecretion 2° to receptor upregulation and inhib. of ATPase recycling. Tachyphylaxis—50% less effective after 6 months. Rebound hypersecretion 2° to receptor upregulation and inhib. of ATPase recycling. 1 www.brain101.info Name: Famotidine (Pepcid) Name: Aluminum Hydroxide (Maalox) Class: H2 Receptor Antagonist Mech.: Competitive inhib. of the histamine H2 receptor, but not of the H1 Class: Antacid receptor → inhib. of fasting and stim. acid secretion. No disruption of Mech.: Weak base → ↓ gastric acidity. ↑ pH → ↓ peptic activity. circadian rhythm of acid secretion. Inhib. of 80-90% of gastrin and Absorption: vagal-stim. acid secretion. Dist.: Absorption: Oral → rapid, good absorption. Single nighttime dose. Metab.: Dist.: Metab.: Partial hepatic metab. Excretion, t_: Excretion, t_: Excreted intact in urine. 1.5-3 hr. Toxicity/S.E.s: Constipation. Al3+ can form insoluble complexes w/other drugs Toxicity/S.E.s: Uncommon. Diarrhea, headaches, myalgias, skin rashes. → ↓ absorption (e.g., tetracycline). Occasional cardiac arrhythmias (more common than in other H2RAs). Utility: PUD Utility: PUD, Zollinger-Ellison synd., acute stress ulcers, GERD Special Features: Special Features: Potency—famotidine > ranitidine/nizatidine > cimetidine. Tachyphylaxis—50% less effective after 6 months. Rebound hypersecretion 2° to receptor upregulation and inhib. of ATPase recycling. Name: Omeprazole (Prilosec) Name: Al-Mg Hydroxides Class: Proton Pump Inhibitor Class: Antacid Mech.: Irreversible inhib. of H+ /K+ ATPase → > 95% inhib. of acid secretion. Mech.: Weak base → ↓ gastric acidity. ↑ pH → ↓ peptic activity. Absorption: Oral → 30-40% bioavail. Peak plasma levels at 0.5-3.5 hr. Give Absorption: prior to meals, preferably in the morning. Additional dose, if Dist.: necessary, should be given later in the day. Metab.: Dist.: Excretion, t_: Metab.: Toxicity/S.E.s: Al3+ can form insoluble complexes w/other drugs → ↓ Excretion, t_: 0.5-1 hr. absorption (e.g., tetracycline). Toxicity/S.E.s: Rare headache, diarrhea, rash. Inhib. of cyt. P-450 requires Utility: PUD altered doses of warfarin, phenytoin, diazepam, and cyclosporin. Inhib. of vitamin. B12 absorption. Special Features: Comb. of constipation (Al) and laxative (Mg) effects may cancel → rel. normal bowel function. Utility: PUD, erosive esophagitis, Zollinger-Ellison synd., GERD. Special Features: Mismatch between pharmacokinetics & pharmacodynamics. Short t_, but actions last > 24 hr (irreversible binding). Acid inhib. → ↑ gastrin. 2 www.brain101.info Name: Magnesium Hydroxide (Milk of Magnesia) Name: Misoprostol (Cytotec) Class: Antacid Class: Prostaglandin Analogue (PGE1) Mech.: Weak base → ↓ gastric acidity. ↑ pH → ↓ peptic activity. Mech.: Stim. mucus and bicarbonate secretion, mucosal blood flow, cell turnover. Inhib. acid secretion. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Longer t_ than natural prostaglandins. Toxicity/S.E.s: Diarrhea. Utility: PUD Toxicity/S.E.s: ↑ intest. secretion → diarrhea. Nausea. Uterine contractions. Special Features: ∴ c/i during pregnancy. Utility: PUD, prevention of NSAID injury. Special Features: Name: Calcium Carbonate (Tums, Rolaids) Name: Bismuth-Subsalicylate (Pepto-Bismol) Class: Antacid Class: Cytoprotective Agent/Hydrophilic Agent/Absorbent/Antimicrobial. Mech.: Weak base → ↓ gastric acidity. ↑ pH → ↓ peptic activity. Mech.: Inhib. pepsin activity, ↑ mucus secretion, coats & protects ulcer. Absorption: Antimicrobial action. May have antiinflammatory action. Dist.: Absorption: Metab.: Dist.: Excretion, t_: Metab.: Toxicity/S.E.s: Excretion, t_: Utility: PUD Toxicity/S.E.s: Binds tetracyclines. Turns stools and tongue black. Contains Special Features: Counterproductive—Ca2+ stimulates gastrin release. salicylate → additive effects w/aspirin, tinnitus. Don’t use w/salicylate allergy. May cause GI impaction in debilitated patients. Utility: PUD. Traveler’s Diarrhea (at least in Mexico)—8 doses (1-2 tablets every eight hours). Prophylaxis for Traveler’s Diarrhea. General diarrhea (usu. controls diarrhea w/in 24 hr). Special Features: 3 www.brain101.info Name: Sucralfate (Carafate) Name: Metronidazole (Flagyl) Class: Cytoprotective Agent Class: Nitroimidazole derivative Mech.: Complex of aluminum hydroxide and sulfated sucrose. Forms complex Mech.: Inhib. DNA synth, degrades DNA, e- acceptor for reduced substrates. gels w/mucus → physical barrier than impairs diffusion of HCl and Absorption: Complete, quick oral absorption. prevents peptic mucus degradation. Stim. prostaglandin release and Dist.: Well distrib to all tissues and fluids (including CSF) secretion of mucus and bicarbonate. Inhib. acid secretion by ~50%. Metab.: Hepatic metab. Absorption: Not absorbed. Excretion, t_: Dist.: Toxicity/S.E.s: GI, metallic taste, neurotox (vertigo), disulfiram-like effect Metab.: w/alcohol, neutropenia. Not for first trimester preg (mutagenic). Excretion, t_: Not for patients w/active CNS disease or hist. of blood Toxicity/S.E.s: Well tolerated. dyscrasias. Utility: PUD Utility: IV treatment of anaerobic infects. Oral for amebiasis, giardiasis, and genital infects of Trichomonas vaginalis. H. pylori (PUD). Special Features: Largely supplanted by H2RAs and PPIs. Requires acidic pH Special Features: Antiparasitic and antibacterial activity. All anaerobic cocci for activation. ∴ should not be admin. w/antacids, PPIs, or and anaerobic gram- bacilli, including Bacterioides. H2RAs. Trichomoniasis, amebiasis, giardiasis. Name: Pirenzipene Name: Amoxicillin (Amoxil) Class: -Muscarinic Antagonist Class: Penicillin (Aminopenicillin) Mech.: M1-inhib. → suppression of gastrin-stimulated and basal acid secretion Mech.: Binds to PBPs, blocks activity of transpeptidases in terminal stages of at doses that have a minimal effect on salivary glands, heart, and eyes. cell wall formation. Bactericidal. Absorption: Absorption: Acid stable. Good oral (better than ampicillin). Dist.: Distrib.: Widely distributed, little CSF unless meninges inflamed. Metab.: Metab.: Excretion, t_: Excretion, t_: Rapidly elim. by kidneys (probenecid blocks excretion), small amt. in bile. Toxicity/S.E.s: Toxicity/S.E.s: diarrhea (less than ampicillin), hypersensitivity (1-10%), Utility: PUD. superinfection. Special Features: 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. 4 www.brain101.info Name: Tetracycline (Achromycin V) Name: Methylcellulose Class: Tetracycline Class: Laxative (Bulk-Forming Agent) Mech.: Active uptake into bacteria →inhib protein synth by binding to 30S ribosome. Bacteriostatic Mech.: Absorbs and retains water, increases fecal volume → ↑ rate of transit. Absorption: Oral adequate, but incomplete. Impaired by divalent cations. IM Absorption: Not absorbed. painful. IV may cause thrombophlebitis. Never intrathecal. Dist.: Distrib.: Good CSF. Conc. in liver → enterohepatic circ. Penetrates most Metab.: tissues and fluids. Crosses placenta. Metab.: Excretion, t_: Excretion, t_: filtration (1°), bile Toxicity/S.E.s: Can bind other drugs → reduced absorption. Admin. > 1 hr Toxicity/S.E.s: GI — burning, discomfort, nausea, vomiting; superinfection — due to broad before or after other medication. spectrum, candida albicans (1°), staph enterocolitis, pseudomemb. colitis; hepatotoxicity (esp. in pregnancy); renal toxicity; Fanconi synd.; perm. brown Utility: Laxative. Esp. useful in pts. w/alternating constipation and diarrhea discoloration of teeth; slowing of bone growth; phototoxicity; thrombophlebitis; (e.g., irritable bowel synd) → ↓ fluidity of liquid stools and softening of hematopoetic changes; rare hypersens. rxns. hard stools. Also useful for pts who are on low residue diets; are Utility: gram - cocci, gram - bacilli, acid fast bacilli, chlamydiae, mycoplasma, postpartum; are elderly; or have diverticular disease, spastic colon, or rickettsia, spirochetes. No effect on viruses or fungi. Also used for hemorrhoids. acne, prophylaxis for Travelers’ diarrhea. H. pylori (PUD). Special Features: Inert, hydrophilic. Introduce gradually to avoid GI impaction. Special Features: Broad spectrum. Decreased effect of oral contraceptives. Gentle agent. Requires 1/2-3 days for effect. Name: Psyllium (Metamucil) Name: Magnesium Sulfate Class: Laxative (Bulk-Forming Agent) Class: Laxative (Saline Cathartic) Mech.: Absorbs and retains water, increases fecal volume → ↑ rate of transit. Mech.: Nonabsorbable ions→ ↑ osmotic pressure in bowel → watery stools in Absorption: Not absorbed. 1-3 hr. Dist.: Absorption: Not much. Metab.: Dist.: Excretion, t_: Metab.: Excretion, t_: Toxicity/S.E.s: Can bind other drugs → reduced absorption. Admin. > 1 hr before or after other medication. 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 Utility: Laxative. Esp. useful in pts. w/alternating constipation and diarrhea low Na+ diets). Potential problem of dehydration. (e.g., irritable bowel synd) → ↓ fluidity of liquid stools and softening of Utility: Acute evacuation of bowel in preparation for endoscopic exam. Elim. of hard stools. Also useful for pts who are on low residue diets; are drugs/toxins for suspected drug/food poisoning. postpartum; are elderly; or have diverticular disease, spastic colon, or hemorrhoids. Special Features: Special Features: Inert, hydrophilic. Introduce gradually to avoid GI impaction. Gentle agent. Requires 1/2-3 days for effect. 5 www.brain101.info Name: Polycarbophil And this is the Noble Truth of Sorrow. Birth is sorrow, age is sorrow, Class: Laxative (Bulk-Forming Agent) disease is sorrow, death is sorrow; contact with the unpleasant is sorrow, separation from the pleasant is sorrow, every wish unfulfilled is sorrow—in short Mech.: Absorbs and retains water, increases fecal volume → ↑ rate of transit. all the five components of individuality are sorrow. Absorption: Not absorbed. And this is the Noble Truth of the Arising of Sorrow. It arises from Dist.: craving, which leads to rebirth, which brings delight and passion, and seeks Metab.: pleasure now here, now there—the craving for sensual pleasure, the craving for Excretion, t_: continued life, the craving for power. Toxicity/S.E.s: Can bind other drugs → reduced absorption. Admin. > 1 hr And this is the Noble Truth of the Stopping of Sorrow. It is the complete before or after other medication. stopping of that craving, so that no passion remains, leaving it, being emancipated from it, being released from it, giving no place to it. Utility: Laxative. Esp. useful in pts. w/alternating constipation and diarrhea And this is the Noble Truth of the Way to the Stopping of Sorrow. It is (e.g., irritable bowel synd) → ↓ fluidity of liquid stools and softening of the Noble Eightfold Path—Right Views, Right Resolve, Right Speech, Right hard stools. Also useful for pts who are on low residue diets; are postpartum; are elderly; or have diverticular disease, spastic colon, or Conduct, Right Livelihood, Right Effort, Right Mindfulness, and Right hemorrhoids. Concentration. Special Features: Inert, hydrophilic. Introduce gradually to avoid GI impaction. —The Buddha Gentle agent. Requires 1/2-3 days for effect. Name: Magnesium Hydroxide Name: Magnesium Citrate Class: Laxative (Saline Cathartic) Class: Laxative (Saline Cathartic) Mech.: Nonabsorbable ions → ↑ osmotic pressure in bowel → watery stools in Mech.: Nonabsorbable ions→ ↑ osmotic pressure in bowel → watery stools in 1-3 hr. 1-3 hr. Absorption: Not much. Absorption: Not much. Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Toxic levels of Mg2+ may accumulate in infants, old folk, and 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 pts. w/impaired renal fxn. Large amount of Na+ (prob. for pts. on low Na+ diets). Potential problem of dehydration. low Na+ diets). Potential problem of dehydration. Utility: Acute evacuation of bowel in preparation for endoscopic exam. Elim. of Utility: Acute evacuation of bowel in preparation for endoscopic exam. Elim. of drugs/toxins for suspected drug/food poisoning. drugs/toxins for suspected drug/food poisoning. Special Features: Special Features: 6 www.brain101.info Name: Sodium Phosphate Name: Phenolphthalein (Ex-Lax) Class: Laxative (Saline Cathartic) Class: Laxative (Contact Cathartic) (Diphenylmethane Cathartic) Mech.: Nonabsorbable ions → ↑ osmotic pressure in bowel → watery stools in Mech.: Act on colon → ↑ peristalsis. Effects take at least 6 hr. to manifest. 1-3 hr. Absorption: Oral → 15% absorption Absorption: Not much. Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Fluid and electrolyte depletion, abdominal cramping, ashes, Toxicity/S.E.s: Large amount of Na+ (prob. for pts. on low Na+ diets). Potential osteomalacia. Potential for atonic colon w/prolonged use. problem of dehydration. Utility: Laxative. Utility: Acute evacuation of bowel in preparation for endoscopic exam. Elim. of drugs/toxins for suspected drug/food poisoning. Special Features: Indiv. effective doses vary 4-8x. Acid/base indicator → Special Features: 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: Bisacodyl (Dulcolax) Name: Bisacodyl Tannex (Clysodrast) Class: Laxative (Contact Cathartic) (Diphenylmethane Cathartic) Class: Laxative (Contact Cathartic) (Diphenylmethane Cathartic) Mech.: Act on colon → ↑ peristalsis. Effects take at least 6 hr. to manifest. Mech.: Act on colon → ↑ peristalsis. Absorption: Oral → 5% absorption. Enema, suppositories (can be irritating). Absorption: Enema. Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Fluid and electrolyte depletion, abdominal cramping, metabolic Toxicity/S.E.s: Fluid and electrolyte depletion, abdominal cramping, metabolic acidosis or alkalosis, hypocalcemia, tetany. Potential for atonic acidosis or alkalosis, hypocalcemia, tetany. Tannic acid in large colon w/prolonged use. amounts is hepatotoxic. Use caution w/multiple enemas. Don’t use in pts. w/colonic ulcers or in kids < 10 y.o. Don’t use > 7.5 Utility: Preparation of colon for surgery or X-ray. g at a time or > 10 g over 72 hr. Special Features: Most useful contact cathartic. Indiv. effective doses vary 4- Utility: Preparation of colon for surgery or X-ray. 8x. Acid/base indicator → pink/red urine. Contact cathartics are most commonly involved in prolonged cathartic abuse. Should never be used > Special Features: Indiv. effective doses vary 4-8x. Acid/base indicator → 1 wk of regular therapy. Not recommended for initial therapy. pink/red urine. 7 www.brain101.info Name: Anthraquinones (senna, cascara, danthron, aloe) Name: Castor Oil Class: Laxative (Contact Cathartic) (Anthraquinone Cathartic) Class: Laxative (Contact Cathartic) Mech.: Emodin, an anthraquinone, stimulates peristalsis in the colon. Effects Mech.: Broken down in small intest. to ricinoleic acid (anionic surfactant) → gut take > 6 hr. to develop. irritation → ↑ peristalsis. ↓ small intest. absorption of electrolytes and Absorption: water, ↑ speed of transit through GI tract. Effective in as little as 2 hr. Dist.: Breast milk. Absorption: Metab.: Dist.: Excretion, t_: Partial kidney excretion (may color urine). Metab.: Toxicity/S.E.s: Excessive catharsis. Colored urine. Not to be used by nursing mothers. Excretion, t_: Utility: Laxative Toxicity/S.E.s: Must not be used chronically → ↓ nutrient absorption. Violent Special Features: Activated by intestinal microflora. More complete evacuation uterine and abdominal cramping. than diphenylmethanes. Contact cathartics are most commonly Utility: Laxative involved in prolonged cathartic abuse. Should never be used > 1 wk Special Features: Contact cathartics are most commonly involved in prolonged of regular therapy. Not recommended for initial therapy. cathartic abuse. Should never be used > 1 wk of regular therapy. Not recommended for initial therapy. Name: Lactulose (Constilac, Cephulac) Name: Lubricant Oils (mineral oil, olive oil, etc.) Class: Laxative (Osmotic Laxative) Class: Laxative Mech.: Galactose-fructose disaccharide → osmotic effect in small intest. In Mech.: Coat stomach contents, change consistency of stool, reduce water absorption. colon, metab. by bacteria to lactic, formic, and acetic acids → osmotic effect. Absorption: Oral, enema. Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Oil absorption → foreign body rxn. Possible lipid pneumonia. Toxicity/S.E.s: Not for use in pts on low galactose diets. Antacids can block Decreased absorption of fat-soluble nutrients. fecal acidification (→ ↓ effect on portal-systemic encephalopathy). Neomycin interferes w/lactulose action. Utility: Laxative. Mineral oil enemas relieve fecal impaction. Special Features: Seldom given orally, as better agents are available. 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. 8 www.brain101.info Name: Docusates (Colace, Doxinate) Name: Kaolin-Pectin (Kaopectate) Class: Laxative Class: Antidiarrheal Drug (Hydrophilic Agent/Absorbent) Mech.: Anionic surfactant. Becomes emulsified w/stool → softer feces, easier Mech.: Kaolin + pectin. Absorb water, bacteria, virus, toxins, bile acids. passage. Requires 1-3 days for action. Decrease fluidity of formed stool. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: May increase intestinal absorption of other drugs. Don’t use Toxicity/S.E.s: May increase water and electrolyte loss. May absorb nutrients, w/lubricant oils. May be mutagenic to cultured liver cells. folate, drugs. Utility: Laxative. Use limited to keeping stool soft. Utility: Treat diarrhea. Special Features: Only a minimal laxative effect at recommended dosage. Special Features: Not terribly effective. Name: Diphenoxylate-Atropine (Lomotil) Class: Opioid (Antidiarrheal) Mech.: 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 Objections, digressions, gay mistrust, the delight in Dist.: Metab.: mockery are signs of health: everything unconditional Excretion, t_: belongs in pathology. 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 → ↓ —Nietzsche 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. 9 www.brain101.info Name: Loperamide (Imodium) Name: Paregoric Class: Opioid (Antidiarrheal) (OTC) Class: Opioid (Antidiarrheal) Mech.: Increased gastric tone → delayed gastric emptying. Increase tone and Mech.: Preparation of oral morphine, anise oil, benzoic acid, camphor, diluted decreased propulsive peristaltic waves in large intest. → decreased gut alcohol, and glycerin. Increased gastric tone → delayed gastric emptying. ↑ motility. Effects due to inhib. of ACh release by neurons in the intest. tone and ↓ propulsive peristaltic waves in large intest. → ↓ gut motility. wall. Naloxone sensitive. Anti-secretory effect (non-naloxone Effects due to inhib. of ACh release by neurons in the intest. wall. Naloxone sensitive). sensitive. Absorption: Oral Absorption: Oral Dist.: Dist.: 90% → GI tract and liver. Very little CNS. Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Toxicity/S.E.s: ↓ peristalsis → ↓ evacuation of bacteria and toxins. Utility: Antidiarrheal. Special Features: 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: Difenoxin-Atropine (Motofen) Name: Norfloxacin (Noroxin) Class: Opioid (Antidiarrheal) Class: Fluorinated quinolone Mech.: Increased gastric tone → delayed gastric emptying. ↑ tone and ↓ Mech.: Inhib bact. DNA gyrase (topoisomerase II). Bactericidal. 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 admin. Absorption: Oral Distrib.: Good tissue penetration. Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Recommended dose → dizziness, drowsiness, mild euphoria. Toxicity/S.E.s: Usu. not severe. GI, CNS. Not for pregnant or nursing women or prepubertal children. Excessive doses → pronounced euphoria, potentially serious respiratory Utility: UTIs due to Enterobacteriaceae, Enteroccus, Staph, Pseudomonas. depression (may not be evident until 12-30 hr later). ↓ peristalsis → ↓ Infectious diarrhea. evacuation of bacteria and toxins. Use w/great caution in kids. Potentiates Special Features: Broader spectrum than nonfluorinated quinolones. For effects of barbiturate, tranquilizers, alcohol, other narcotics. Hypertensive diarrhea, treat until symptoms resolve, or no longer than 3 crisis w/MAOI. days. Utility: Antidiarrheal. Special Features: Difenoxin has 5x potency of diphenoxylate. Atropine included primarily to prevent drug abuse. Kids esp. sensitive to atropine toxicity. 10 www.brain101.info Name: Ciprofloxacin (Cipro) Name: Trimethoprim-Sulfamethoxazole (Bactrim, Septra) Class: Fluorinated quinolone Class: Antimicrobial Mech.: Inhib bact. DNA gyrase (topoisomerase II). Bactericidal. Mech.: Acts on two sequential steps in synth of folic acid. PABA competitive inhib, dihydrofolate reductase inhib. Bacteriostatic. Absorption: Rapid absorption after oral admin. Absorption: Oral, IV Distrib.: Good tissue penetration. Poor CSF. Distrib.: Metab.: Partial hepatic metab. Metab.: Excretion, t_: Glomerular filtration, secretion. Also feces, bile, sputum. 4 hr. Excretion, t_: Toxicity/S.E.s: Usu. not severe. GI, CNS, arthropathy. Not for pregnant or Toxicity/S.E.s: Megaloblastic anemia, leukopenia, granulocytopenia (prevented nursing women or prepubertal children. by admin. of folic acid) Utility: Upper and lower UTIs, DOC for Pseudomonas UTIs. Active against Utility: Uncomp. UTIs, otitis media, acute exacerbations of chronic bronchitis, aerobic gram- bacilli, H. influenzae, Neisseria. Good for several causes various pneumonias. DOC for Travelers’ diarrhea (esp. in kids), P. of infectious diarrhea, osteomyelitis, and patients w/CF. carinii pneumonia, Shigella enteritis, systemic Salmonella infects, Special Features: Broader spectrum than nonfluorinated quinolones. For prostatitis. diarrhea, treat until symptoms resolve, or no longer than 3 Special Features: Trimethoprim = highly selective inhib. of bacterial days. dihydrofolate reductase. For diarrhea, treat until symptoms resolve, or no longer than 3 days. Name: Ofloxacin (Floxin) Name: Vitamin D Class: Fluorinated quinolone Class: Mech.: Inhib bact. DNA gyrase (topoisomerase II). Bactericidal. Mech.: Facilitates intest. absorption of Ca2+ and PO43-, and mineralization of Absorption: Oral admin. bone. Distrib.: Good tissue penetration. Absorption: Metab.: Dist.: Excretion, t_: Metab.: Toxicity/S.E.s: Usu. not severe. GI, CNS. Not for pregnant or nursing women Excretion, t_: or prepubertal children. Toxicity/S.E.s: Megadose—hypercalcemia. Utility: UTIs due to Enterobacteriaceae, Enteroccus, Staph, Pseudomonas. Utility: Infectious diarrhea. Special Features: Quasi-vitamin—synthesized in humans. RDA inversely Special Features: Broader spectrum than nonfluorinated quinolones. For proportional to amount of UV light exposure. Deficiency → diarrhea, treat until symptoms resolve, or no longer than 3 rickets (kids), osteomalacia (adults). days. 11 www.brain101.info Name: Vitamin C Name: Vitamin A Class: Class: Mech.: Mech.: Component of visual pigment. Maintains specialized epithelia and Absorption: resistance to infxn. Dist.: Absorption: Metab.: Dist.: Excretion, t_: Metab.: Toxicity/S.E.s: Diarrhea. Megadose—diarrhea, kidney stones, precipitation of Excretion, t_: sickle cell crisis, transient infertility, altered renal secretion of Toxicity/S.E.s: Megadose—teratogenic (face, head, brain, heart), thickening of weak acids and bases. the leg bones, ↑ intracranial pressure. Utility: Large doses may reduce rate of buildup of atherosclerotic plaques in Utility: coronary arteries and protect against stroke and heart disease. Special Features: Deficiency → night blindness, xerophthalmia, blindness, Special Features: TB pts. probably need 2x normal amount of vitamin C. squamous metaplasia, infxn vulnerability (esp. measles). Liver damage → ↑ need. Name: Vitamin E Name: Folic Acid Class: Class: Mech.: Fat soluble antioxidant. Scavenges free radicals. Conc. in adipose Mech.: Essential for transfer and utilization of 1-carbon units in DNA synth. tissue. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Toxicity/S.E.s: Diarrhea, headache. Utility: Recommended for all premenopausal women at dose of 2 x RDA → Utility: Large doses may reduce rate of buildup of atherosclerotic plaques in reduced risk of neural tube defects. Lowers homocysteine, reduces risk coronary arteries and protect against stroke and heart disease. of heart disease. May lower risk of cervical cancer. Treat folate- Special Features: RDA directly proportional to intake of polyunsaturated fatty responsive schizophrenia (50-150 x RDA → ↓ buildup of urinary acids. Deficiency → spinocerebellar degeneration. homocysteine → ↓ psychiatric symptoms). Special Features: Deficiency → megaloblastic anemia. Alcoholism → ↓ folate absorption. Pregnancy → ↑ folate demand. 12 www.brain101.info Name: Vitamin K Name: Vitamin B2 (Riboflavin) Class: Class: Mech.: Cofactor in hepatic carboxylation of procoagulants—factors II, VII, IX, Mech.: Converted to coenzymes FMN and FAD. and X. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Toxicity/S.E.s: Utility: Utility: Antagonize coumarin anticoagulation (min. dose = 60-100 x RDA). Special Features: Deficiency → ariboflavinosis, cheilosis, stomatitis, glossitis, Infants given injxn (infant GI tract lacks microbes that produce vitamin K). dermatitis, corneal vascularization. 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 B1 (Thiamine) Name: Vitamin B6 (Pyridoxine) Class: Class: Mech.: Coenzyme in decarboxylation rxns. Facilitates conduction of impulses Mech.: Derivatives serve as coenzymes in many intermed. rxns. in peripheral nerves. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Megadose—severe (often irreversible) sensory neuropathy Toxicity/S.E.s: Utility: Utility: Special Features: Deficiency → cheilosis, glossitis, dermatitis, peripheral Special Features: Deficiency → dry & wet beriberi, Wernicke-Korsakoff’s synd. neuropathy. Liver damage → ↑ need. Penicillamine, RDA directly proportional to caloric intake. Deficiency hydralazine, and isoniazid complex w/B6 → ↓ B6. B6 is a common in alcoholics. cofactor of tryptophan → nicotinic acid conversion. Results in ↓ B3. Pregnancy → ↑ B6 demand. 13 www.brain101.info Name: Vitamin B3 (Niacin) Name: Biotin Class: Class: Mech.: Incorporated into NAD and NADP. Mech.: Incorporated in coenzyme A. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Toxicity/S.E.s: Utility: Utility: Special Features: Deficiency → pellagra (dementia, dermatitis, diarrhea). Special Features: Some antibiotics kill gut microbes that synthesize biotin. Penicillamine, hydralazine, and isoniazid complex w/B6 → ↓ B6. B6 is a cofactor of tryptophan → nicotinic acid conversion. Results in ↓ B3. Name: Vitamin B12 (Cyanocobalamin) Name: Iodine Class: Class: Mech.: Necessary for folate metabolism and DNA synth. Maintains Mech.: 80% contained in thyroglobulin. myelinization of spinal cord tracts. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Toxicity/S.E.s: Utility: Utility: Special Features: Deficiency → endemic goiter. Excess (>20 x RDA) → Special Features: Vegan diet → deficiency → megaloblastic pernicious anemia blocked organification of iodine → myxedema. and degeneration of posterolateral spinal cord tracts. If patient is deficient in B12 and folate, replace B12 first to avoid irreversible neuro damage. Liver damage → ↑ need. 14 www.brain101.info Name: Zinc Name: Copper Class: Class: Mech.: Part of many metalloproteins (e.g., “zinc fingers”). Element of carbonic Mech.: Present in muscle, bone, liver, blood. In blood, almost entirely bound to anhydrase. ceruloplasmin. Component of many metalloenzymes such as Absorption: cytochrome oxidase and tyrosinase. Dist.: Absorption: Metab.: Dist.: Excretion, t_: Metab.: Toxicity/S.E.s: Excretion, t_: Utility: Toxicity/S.E.s: Special Features: Kids w/low Zinc often grow poorly and have a poor appetite Utility: (prob. 2° to impaired taste). Special Features: Excess plasma free copper may be due to Wilson’s Disease (defective ceruloplasmin) or excessive intake. Name: Selenium Name: Fluoride Class: Class: Mech.: Present in glutathione peroxidase which destroys peroxides derived Mech.: Present in bones and teeth. Fluoridation of drinking water at 1 ppm → ↓ from unsaturated fatty acids. Probably has a close functional dental caries by 30-40%. Hardens outer layers of tooth enamel. Makes relationship w/vitamin E. enamel more resistant to demineralization. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Toxicity/S.E.s: Utility: Utility: Special Features: RDA probably directly proportional to intake of Special Features: Excess (> 10 ppm in water) → fluorosis (mottling of teeth) polyunsaturated fatty acids. due to excess accumulation in teeth and bones. 15 www.brain101.info Name: Manganese Name: Cobalt Class: Class: Mech.: Present in several enzymes, required for normal bone structure. Mech.: Present in vitamin B12. Absorption: Absorption: Dist.: Dist.: Metab.: Metab.: Excretion, t_: Excretion, t_: Toxicity/S.E.s: Toxicity/S.E.s: Utility: Utility: Special Features: No reported deficiencies. Excess limited to manganese Special Features: No known deficiency states. miners. Name: Chromium Class: Mech.: Part of several metalloenzymes For one thing is needful: that a human being attain Absorption: satisfaction with himself - whether it be by this or by that Dist.: poetry and art; only then is a human being at all tolerable Metab.: Excretion, t_: to behold. Whoever is dissatisfied with himself is always Toxicity/S.E.s: ready to revenge himself; and therefore we will be his Utility: victims if only by always having to stand his ugly sight. Special Features: Deficiencies only in severely protein-deprived pts and pts. For the sight of the ugly makes men bad and gloomy. w/prolonged parenteral feeding. - Nietzsche 16 www.brain101.info