Gastrointestinal drugs PDF

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Summary

GI drug summary...

Description

Gastrointestinal drugs Class

Type Antacids

Action/Effect/use Buffer/neutralized HCL in stomach reducing gastric PH reduces total acid load, allowing ulcers to heal

adverse effects  

Diarrhea (mg) Constipation (Al/Ca)

Contraindications 

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 H2RAs Histamine 2 receptor antagonists

Blocks stimulating effect of histamine of parietal cells of the stomach Reduces acid secretion, use for Reflux esophagitis, peptic ulcer, prevention of ulcers

Proton pump inhibitor  newer used often

Blocks final step in acid production Treats H pylori, erosive gastritis, active ulcer, zollinger-ellison syndrome

Sulcralfate

Non-absorbing paste that coats ulcerated areas while healing Does not alter GI activity Duodenal orders Antisecretory, mucosal protective prevents GI ulcers in patients taking NSAIDS without interfering with the NSAID

Prostaglandins

Produce vomiting rarely used

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Headache Diarrhea Skin rash Gynecomastia ↓ libido Hypotension/brady cardia Thrombocytopenia granulocytepenia

  few:  Nausea  Diarrhea  Headache  ↑ MI

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Rare: constipation

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Diarrhea

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Avoid Mg compounds if renal disease Use with caution in cardiac renal or hypertensive Can decrease absorption do not give within 1 hr. of antacid

Nursing implication 

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Drug interactions

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Drug interactions

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Examples

Take 1 hr. before meals of 3 hours after/at hs

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Monitor for drug interactions Dilute for IV Monitor if rapid IV Provide education

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Take before meals Administer 2 hrs. before or after other drugs Ensure it is taken throughout NSAID therapy

Maalox (al & mg) Mylanta (al/mg) Riopan (mg) Amphogel (al) Roliads (ca) Tums (ca) Cimetidine (Tagamet) *rarely used ranitidine (Zantac) famotidine (Pepsid).

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Prevacid Prilosec Losec Pantoloc Nexium Pariet

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Misoprostol (cytotec)

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Ipecac

Anticholinergic

Bind to and block ACh on vestibular nuclei of brain and the reticular formation Dry gastric secretions and reduce smooth muscle contraction ↓ N/V

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Block H1 receptors in VC Used with N/V associated with inner ear stimulation post op N/V

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Block Dopaminergic receptor in CTZ of brain Severe N/V (CA) When other antiemetics are inefrective

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Setatonin Blockers (5-HT3 receptor antagonists)

Increase peristaltic activity by increasing rate of ACh release GERD, Gastroparesis antagonize serotonin receptors, preventing activation N/V associated with CA and post op

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Tetrahydrocanninbi noids

Central effect to reduce N/V N/V CA and Appetite stimulant in HIV/AIDS

Antihistamines

Neuroleptics (Phenothiazine)

Prokinetic agents

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CNS- dizziness, drowsiness, disorientation Tachycardia Constipation Blurred vision Dilated pupils

Drowsiness Paradoxical CNS stimulation in children Dry Mouth

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↓ CNS if taken with barbiturates, tranqs, ETOH, Opiates

CNS: confusion, euphoria, weakness, agitation

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Drug interactions

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increase depression restlessness extrapyramidal rxns Diarrhea HA Dizziness Constipation Muscle aches Elevation of Liver enzymes abuse withdrawal

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Most effective if given prophylactically

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dimenhydrate (Gravol)

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promethazine (Hismanal) Prochloperazine (Nu-Prochlor) Stemitil metaclopromide (Maxeran)

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decrease absorption of other drugs

ondansetron (Zofran)

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dronabinol (Marinol) nabilone (Cesamex)

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attapuglite (Kaopectate) bismuth subsalicylate (Pepto-bismol)

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watch for overuse/dependenc

to relieve symptoms of diarrhea/underlying cause Adsorbent

Coat the wall of intestinal tract and bind with causative bacteria or toxin treatment of diarrhea and abdominal cramping

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confusion constipation ^ bleeding Hearing loss Tinnitus

Anitmotility

Slow propulsive movement of intestines, reduce pain associated with rectal spasms

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Dry mouth Constipation

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should not be used if pt. has infection

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loperimide (Imodium

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opiate related

most effective

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Narcotic dependence

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anticholinergic s

Slows peristalisis by reducing contraction and smooth muscle tone treatment of diarrhea and abdominal cramping

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hypo/hypertension Bradi/tachycardia headache confusion anxiety ED Urinary retention drowsiness

e

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dyphenoxylate (Lomotil))

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atropine hyoscyamine hyoscine

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Lacidofil

impaction above structures, fluid overload, gas formation decreased absorption of fat soluble vitamins

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psyillium (Metamucil) Polycarbophil calcium methylcellulose (entrocel)

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docusate sodium (Colace) mineral oil (fleet enema mineral oil)

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polyethylene glycol (peglyte) Lactulose sorbitol glycerine Milk of magnesium sodium phosphate (Fleet)

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biscodyl (Dulcolax) castor oil senna (Senokot)

suppress the growth of bacteria causing diarrhea Intestinal flora restore and maintain normal flora modifiers Octerotide: synthetic form of Somatostatin, a hormone that decreases GI secretions/motility. It blocks responses that cause disease symptoms Promote peristalsis Bulk forming

similar to fiber Constipation and IBS/diverticulosis

Emollients

Softener: lowers surface tension increase water and fat Lubricant: lubricates stool and prevents water loss Prevent straining after childbirth, MI, anorectal surgery draw water to intosite, distending it and promoting peristalsis chronic constipation, diagnostics, surgery

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F/E imbalance abdominal bloating

Increase osmotic pressure therefore resulting in water stool and increased peristalsis Constipation, removing unabsorbed poisons, surgical and diagnostic preparation Irritate the intestinal mucosa or stimulating nerve endings of the smooth muscle emptying the bowel prior to surgery acute constipation

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F/E imbalance cramping Mg toxicity

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Nutrient malabsorption GI irritation Cramping F/E imbalance

Hyperosmotic

Saline

Stimulants

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F/E imbalance Dysfunction of bowel dependence

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