Pharm Exam 4: GI drugs

3 acid controlling drugs:

1. Al+= aluminum hydroxide

2. Mg+= magnesium hydroxide

3. Ca+ = calcium carbonate

Histamine H2 Antagonists: (3)

1. ranitidine

2. cimetidine

3. famotidine

PPI drug:

omeprazole

Mucosal protectant:

sucralfate

Prostaglandin E Analong

Misoprostol

Anti motility drug:

Opiates

• loperamide (Immodium)

Bulk forming “fiber” drug

psyllium

Surfactant “stool softener” drug

docusate sodium

Stimulant laxative drug:

biscodyl

Important notes abt acid-controlling drugs: (5)

1. doesn’t prevent acid production and may inhibit absorption of drugs needing acidic envt

2. caution EC meds

3. long term use may mask serious illness—call HCP if lasts 2+ weeks

4. admin other meds 1-2 hrs AFTER antacids

5. give w/ 8 oz water

Adverse effect of aluminum hydroxide:

• OK or NOT ok w/ renal failure?

• Constipation

• OK w/ renal disease

Adverse effect of magnesium hydroxide:

• OK or NOT ok w/ renal failure?

• Diarrhea

• dangerous w/ renal failure!!

Calcium carbonate adverse effects: (3)

• OK or NOT ok w/ renal failure?

1. constipation

2. kidney stones

3. rebound hyperacidity

• NOT for pts/ w renal failure

Histamine H2 antagonists MOA:

decrease acid

Adverse effects of histamine H2 antagonists—cimetidine/famotidine: (3)

1. Cimetidine:

   • confusion and disorientation in elderly

2. Famotidine:

   • constipation

3. May inhibit absorption of drugs needing acidic environment

Nursing implications for histamine H2 antagonists: (2)

1. Smoking decreases effectiveness

2. Short term use (2 weeks)— then seek HCP

PPI MOA: (2)

• 1. Binds to H+/K+ enzymes— preventing movement of H+ from parietal cells to stomach

  2. causes achlorhydria

What is achlorhydia?

all gastric acid temporarily blocked when taking omeprazole

Short and long (3) term effects taking omeprazole:

1. Short: NVD & HA

2. Long:

   a. Osteoporosis/ Fractures

   b. Rebound acid hypersecretion

   c. HYPOmagnesemia

Nursing implications taking PPI: (2)

1. H. Pylori tx: PPI used w/ abx for 2 weeks for H. Pylori

2. Possible GI infection (C.DIFF!!!)

Sucralfate MOA: (2)

1. cytoprotective

2. “band-aid”

2 indications of sucralfate:

1. stress ulcers

2. can be used to decrease phosphate in CRF as binds w/ phosphate

Nursing implication sucralfate:

• give other drugs 2 hrs B4 sucralfate to avoid impaired absorption

misoprostol contraindication:

Pregnancy X

• abortive drug (miscarriages)

Nursing implication misoprostol:

stop taking if ur preggo!!

Antidiarrheal important notes: (2)

• goal (4)

1. Diarrhea is a symptom, not disease—can be acute or chronic

2. GOAL of tx:

   • stop stool frequency

   • alleviate abd cramps

   • replenish F&E

   • prevent weight loss and nutritional deficits

loperamide MOA:

an opiate— decreases GI motility and reduce pain by relief of rectal spasms

Indication of loperamide:

stop/ decrease frequency of diarrhea

Adverse effects of loperamide: (2)

1. high doses —> euphoria, CNS and respiratory depression, urinary retention

2. At recommended dose—> no opiate or anticholinergic adverse effects

Nursing implications loperamide: (4)

1. packaging only 8-12 tabs “poor mans methadone”— heart problems and death

2. Initially 4mg, then 2 mg after EACH loose stool to max of 16mg/ day

3. Loperamide is OTC, no physical dependence

4. Asses fluid vol status, monitor I&O, weight and vs

Laxatives Important notes: (2)

1. constipations a symptom

2. contraindication for all lax: NEVER give w/ diagnosis of “abd pain of unknown origin”

psyllium indication:

promotes defecation in older pts

Adverse effect psyllium: (2)

1. Impaction

2. Esophageal blockage

Nursing implication psyllium: (3)

1. can decrease absorption of other meds

2. ONLY lax SAFE to use long term!!!

3. take w/ 8oz fluid—can cause impaction/ blockage!!

docusate sodium indications: (2)

1. prevent painful voiding w/ hemorrhoids and episiotomies

2. prevent straining in pts w/ cerebral aneurysm and POST MI!

Nursing implications docusate sodium: (2)

1. Stool softener— does not aid in defecation—only softening (no straining to go)

2. Take w/ 8oz water/ juice

bisacodyl MOA:

increase peristalsis via intestinal nerve stimulation

Indication of Bisacodyl:

bowel prep for surgery

adverse effect of Bisacodyl:

electrolyte imbalance— mainly Mg+

Nursing implication bisacodyl: (2)

1. give PO w/ water ONLY (8oz)

   • interacts w/ milk, antacids, and juices

2. available as PR (pre rectum) but becomes very crampy