Gastrointestinal Agents

Acid controlling drugs

Neutralizing agents (antacids), H2 blocking agents, proton pump inhibitors

Antacid agents

Calcium carbonate (Alka-Seltzer, Tums), magnesium hydroxide (Milk of Magnesia), calcium carbonate and magnesium hydroxide (Rolaids), aluminum hydroxide, magnesium hydroxide, simethicone (Maalox), sodium bicarbonate (Gaviscon)

Neutralizing agents indications

Used for heartburn/GERD. Calcium carbonate (Tums) may be used for osteoporosis/ osteopenia

Neutralizing agents MOA

Compounds neutralize stomach acid, do not affect acid production

Neutralizing agents contraindications

No magnesium for renal failure patients

Neutralizing agents adverse effects

Aluminum and calcium cause constipation, magnesium causes diarrhea, sodium bicarb causes metabolic alkalosis

Neutralizing agents nursing implications

Monitor for therapeutic response (less symptoms of GERD),adverse effects (constipation/ diarrhea/ metabolic alkalosis), take 1-2 hours before or after medications

Histamine 2 receptor antagonists (H2 blockers)

Cimetidine (Tagamet), famotidine (Pepcid), ranitidine (Zantac)

H2 blockers indications

Heartburn, GERD, peptic ulcer disease (PUD), erosive esophagitis – hyperacidity conditions

H2 blockers MOA

Block H2 receptors of parietal cells, reduce hydrogen ion secretion and increasing pH in the stomach, decrease acid secretion in stomach

H2 blockers contraindications

Allergy

H2 blockers adverse effects

CNS effects in elderly patients, confusion and disorientation

H2 blockers nursing implications

Monitor for therapeutic effects, adverse effects (confusion in elderly), best to take at night

Proton pump inhibitors

Omeprazole (Prilosec), esomeprazole (Nexium), pantoprazole (Protonix), lansoprazole (Prevacid)

Proton pump inhibitors indications

GERD, active gastric ulcers, NSAID induced ulcers, H. pylori infections

Proton pump inhibitors MOA

Binds to proton pump and prevents movement of hydrogen ions out of the parietal cell and blocks all gastric acid secretion

Proton pump inhibitors contraindications

Allergy

Proton pump inhibitors adverse effects

Osteoporosis with long-term use

Proton pump inhibitors nursing implications

Monitor for therapeutic response, adverse effects, monitor for osteoporosis, used to treat ulcers with antibiotic

Antidiarrheal agents

Bismuth subsalicylate (Pepto Bismol), opioids, probiotics

Antidiarrheal agents indications

Mold diarrhea (adsorbents), severe diarrhea (Antimotility: anticholinergic/opioids), antibiotic-induced diarrhea (probiotics)

Adsorbent antidiarrheal agents MOA

Coat wall of GI tract and bind to and neutralizing causative toxins

Opioid antidiarrheal agents MOA

Reduce bowel motility

Probiotic antidiarrheal agents MOA

Replace normal bacterial flora in GI tract

Antidiarrheal agents contraindications

Allergy, intestinal obstruction

Antidiarrheal agents adverse effects

Drug specific, monitor respiratory status and sedation with opioids, Pepto Bismol turns stools and tongue black

Antidiarrheal agents nursing implications

Monitor for therapeutic effects (less frequent BM’s), adverse effects (drug dependency with opioids)

Constipation agents

Psyllium (Metamucil), methylcellulose (Citrucel), docusate Sodium (Colace), polyethylene glycol (Go LYTELY, Miralax), magnesium citrate, senna, bisacodyl (Dolcolax)

Psyllium (Metamucil), methylcellulose (Citrucel)

Increases bulk of stool to stimulate BM

Docusate Sodium (Colace)

Does not stimulate GI motility, softens stool so easier to pass

Polyethylene glycol (Go LYTELY, Miralax)

Increases oncotic pressure inside the colon, pulls water in and stimulates BM, must be well hydrated for this to work

Magnesium citrate

Draws water into intestine to stimulate BM

Senna, bisacodyl (Dolcolax)

Simulate nerves innervating colon to increase GI motility, can cause dependency

Constipation agents indications

Constipation

Constipation agents MOA

Affect fecal consistency; increase fecal movement; facilitate defecation through rectum

Constipation agents contraindications

Drug allergy, intestinal obstruction, undiagnosed abdominal pain

Constipation agents adverse effects

Electrolyte disturbances, gas formation, bloating

Constipation agents nursing implications

Monitor for therapeutic effects (relief of constipation), adverse effects (drug dependence, especially with stimulant laxatives)

Simethicone (Mylicon)

Decreases painful gas (flatulence), breaks down large gas bubbles into smaller ones (easier to expel), OTC, safe (no listed adverse effects)

Antiemetic agents

Anticholinergic drugs, prokinetics, serotonin blockers

Anticholinergic drugs

Scopolamine, dimenhydrinate (Dramamine) for motion sickness, secretion reduction prior to surgery; diphenhydramine, Promethazine (Phenergan); cause drowsiness, same side effects as other antihistamines

Prokinetics

Metoclopramide (Reglan); restlessness, dystonia, also treats delayed gastric emptying

Dystonia

Muscle spasms, uncontrolled movements

Serotonin blockers

Ondansetron (Zofran)

Water soluble vitamins

Dissolved in water and excreted in urine; vitamin B group (B1, B2, B3, B6, B12), vitamin C; not stored in the body in large amounts

Fat soluble vitamins

Stored in liver or fatty tissue; vitamin A, D, E, K; daily intake not required unless one is deficient

Vitamin A (retinol)

Fat soluble vitamin, comes from carotenes in plants (green and yellow vegetables and yellow fruits)

Vitamin A (retinol) functions

Essential for night and normal vision, cholesterol and steroid synthesis

Vitamin B1 (thiamine) indications

Carb metabolism, metabolic pathways (Krebs cycle), integrity of CV system, GI tract and peripheral nervous system

Vitamin B1 (thiamine) food sources

Whole grain bread, fortified cereals and other processed food products

Wernicke’s encephalopathy

Serious neurological condition caused by vitamin B1 deficiency, characterized by confusion, ataxia, and ophthalmoplegia, often associated with alcoholism

Vitamin B3 (niacin)

Lipid lowering agent, can cause flushing

Vitamin B3 (niacin) sources

Beans, turkey, liver, yeast, whole grain bread, cereal

Vitamin B6 (pyridoxine) indications

Many metabolic functions, protein, lipid utilization, integrity of peripheral nerves, skin and mucous membranes; TX for morning sickness and seizures unresponsive to other therapies

Vitamin B6 (pyridoxine) sources

Whole grain, yeast, fish, organ meats, eggs, nuts, bananas

Vitamin B6 (pyridoxine) deficiency causes

Inadequate intake, malabsorption, ETOH abuse, cirrhosis, or drug induced (isoniazid)

Vitamin B12 (cyanocobalamin) indications

Required for metabolic pathways, fat and CHO metabolism, protein synthesis, growth and cell replication, hematopoesis (RBC synthesis)

Vitamin B12 (cyanocobalamin) sources

Microorganisms in body, liver, fish, shellfish, poultry, eggs, blue cheese

Vitamin B12 (cyanocobalamin) deficiency causes

Malabsorption (after gastric bypass d/t lack intrinsic factor in stomach), poor dietary intake

Vitamin B12 (cyanocobalamin) deficiencies

Megoblastic anemia, neurological damage

Vitamin C indications

Acts in red-ox reactions, required for metabolic processes (collagen synthesis, tissue repair, bone/teeth/capillary integrity, folic acid metabolism, immune function, erythropoiesis), enhances iron absorption

Vitamin C deficiency

Scurvy

Scurvy

Bleeding gums, loss of teeth, bone lesions, delayed wound healing

Vitamin D indications

Works with PTH to regulate absorption and use of calcium and phosphorus, necessary for calcification of bone and teeth, treatment of hypoparathyroidism and hypophosphatemia

Vitamin D sources

Synthesized in skin through exposure to sun (cholecalciferol, D3), fish, liver, milk, OJ, cereals, eggs, dairy (ergocalciferol, D2)

Vitamin D deficiency

Rickets, tetany, osteoporosis

Vitamin E indications

Antioxidant, immune system maintenance, helps form RBCs

Vitamin E sources

Fruits, grains cereals, nuts, eggs, chicken, meats, fish

Vitamin K

Body does not store large amounts, given prophylactically to newborns (sterile bowels), reverses effects of warfarin

Vitamin K indications

Synthesis of clotting factors in liver

Vitamin K sources

Synthesized by intestinal flora, green, leafy veggies, cheese, soybean oil

Vitamin K deficiency

Risk of bleeding

Nutritional supplements

Provide nutritional support, can be given via multiple routes (PO, IV, NG/G/J tube), vary in amounts and complexity of CHO, Protein, and fat content; electrolytes, vitamins, minerals and osmolality also varies; treatment for malnutrition

Enteral nutrition indications

Supplementation of oral diet that is insufficient to meet patient’s needs

Enteral nutrition MOA

Provide basic building blocks for anabolism (tissue building), combination of nutrients is patient specific

Enteral nutrition contraindications

Allergy

Enteral nutrition adverse effects

Dumping syndrome (due to rapid feeding), severe diarrhea, digestive intolerances (lactose intolerance, aspiration pneumonia)

Enteral nutrition nursing implications

Monitor for therapeutic response (weight gain, improved LOC/ADL), adverse effects (may have diarrhea due to lactose intolerance or dumping syndrome, must be elevated 30 degrees or more to prevent aspiration pneumonia if using NG tube), check tube placement before initiating continuous feed or bolus feed

TPN indicataions

Nutrients delivered directly into circulation by IV solution (no digestion), given to patients unable to tolerate or absorb nutrients through GI tract, temp solution is used < 2 weeks

TPN MOA

Nutrients delivered directly into blood stream, central line if < 14 days or Dextrose < 12.5%, high infection risk (monitor WBC and temp)

TPN contraindications

Allergy

TPN adverse effects

Phlebitis (can cause loss of limb), fluid overload, infection, hyperglycemia

TPN nursing implications

Monitor for therapeutic response (electrolytes wnl, weight stable, LOC), adverse effects (infection), monitor IV closely (phlebitis), listen to heart/lung sounds (monitor for edema), high (monitor temp and WBC), monitor for hyperglycemia