Acid-Controlling Medications

• These notes cover various medications and their mechanisms of action, nursing considerations, and side effects

Antacids

• Mechanism: Neutralize stomach acid, raising the pH
• Considerations:
  • Take 3-4 times per day
  • Avoid taking with other medications within 1-2 hours due to potential interactions
  • Calcium carbonate may be contraindicated in individuals with kidney disease or hypercalcemia
  • May cause rebound hyperacidity
  • Encourage patients to avoid smoking, alcohol, high-fat foods, spicy foods, and caffeine

H-2 Receptor Antagonists

• Mechanism: Blocks histamine's action at the H2 receptors of the stomach's parietal cells
• Considerations:
  • Take 15-60 minutes before consuming foods that trigger heartburn
  • Dosage adjustments may be necessary for individuals with liver or kidney disease
  • Cimetidine has a high drug interaction risk

Proton Pump Inhibitors (PPIs)

• Mechanism: Binds to the H+-K+ ATPase enzyme system (proton pump), inhibiting hydrochloric acid secretion
• Considerations: Can interfere with liver drug metabolism
• Long-term risks:
  • Zinc, magnesium, and B12 deficiency
  • Increased pneumonia risk
  • Renal dysfunction
  • Osteoporosis
  • Lupus erythematosus

Mucosal Protectants

• Mechanism: Cover and protect GI ulcers from further damage by acid, pepsin, and bile salts
• Considerations:
  • Take on an empty stomach, either 2 hours after or 1 hour before meals
  • Use caution in patients with chronic renal failure due to excretion of small amounts of absorbed aluminum
  • Side effect: Constipation

Antiflatulents

• Mechanism: Alter the elasticity of gas bubbles, breaking them into smaller bubbles
• Considerations:
  • Simethicone can be taken four times a day, after meals and at bedtime
  • Safe for infants
  • Common side effects: nausea, constipation, diarrhea, and headache
  • Encourage position changes, movement, and avoiding straws

Antidiarrheals

• Three types:
  • Adsorbents: Help eliminate toxins/bacteria from the GI tract
  • Antimotility: Slow peristalsis
  • Probiotics: Restore normal bacteria in the lower intestine

Adsorbents

• Mechanism: Coat the walls of the GI tract, bind to causative bacteria/toxins, and eliminate them
• Example: Bismuth
• Reduces the flow of fluids and electrolytes into the bowel and reduce inflammation in the intestine
• Considerations:
  • Bismuth contains salicylate; so avoid it when taking aspirin
  • Assess for Reye's Syndrome
• Contraindications: ulcer/bleeding problems
• Side effects: black or dark tongue and ringing in ears

Antimotility Agents

• Mechanism: Decrease the flow of fluid and electrolytes into the bowel and slows bowel movement
• Two examples: Opioid-like and Anticholinergics

Opioid-like

• Mechanism: Slow down the movement of the intestines, reduce the frequency & volume of bowel movements
  • Have an opioid-like structure, but cause fewer CNS effects
• Example: Loperamide
• Considerations: Taking more than the prescribed amount can result in an abnormal heart rhythm
• Side effects: abdominal discomfort, Nausea/Vomiting, dizziness, and drowsiness

Anticholinergics (Antispasmodics)

• Mechanism: Block the action of acetylcholine in the nervous system and work on smooth muscle of the GI tract to inhibit propulsive motility, and decrease gastric acid secretion
• Examples: dicyclomine (Bentyl), hyoscyamine (Levsin)
• Considerations: Assess for intestinal obstruction
• Contraindications: glaucoma, myasthenia gravis, paralytic ileus
• Side effects: dry mouth, constipation, blurred vision, confusion (especially in older adults)

Probiotics

• Mechanism: Microorganisms that help replenish normal bacterial flora in the GI tract
• Example: lactobacillus
• Considerations: Various strains with different health benefits
• Side effects: gas, bloating, and diarrhea

Laxatives

• List of Laxatives:

Fiber

• Mechanism: Adds bulk to stool to facilitate passage
• Considerations:
  • May affect GI absorption; take 2 hours before other meds
  • Produces a BM in 12-72 hours
  • Start with one dose per day; may increase to 3 doses per day to maintain soft stools

Stool Softeners (Emollient Laxatives)

• Mechanism: Facilitates the movement of water and fats into the stool
• Considerations:
  • Produces a BM in 1-72 hours
  • Monitor electrolyte imbalances
  • May interact with other meds: blood thinners & antibiotics

Osmotic Agents (Lubricant Laxatives)

• Mechanism: Causes water to be retained with the stool, increasing the number of bowel movements and softening the stool so it is easier to pass
• Considerations:
  • Usually produce a BM in 1-3 days
  • Diarrhea and abdominal cramping
  • Electrolyte imbalances
  • Dehydration

Lubricants

• Mechanism: Mineral oil coats stool to help seal in H20
• Example: Mineral oil enema (Fleet enema)
• Nursing Considerations:
  • Produce a BM in 2-15 minutes (Rapid BM)
• Side Effects:
  • Stomach cramps
  • Bloating
  • Diarrhea/dehydration
  • Electrolyte imbalances

Stimulant Laxatives

• BM in 15 minutes
• Mechanism of action: cause contraction of intestines and stimulate stool to move
• Nursing Considerations:
  • PO & Rectal Supply
  • Avoid long-term use ↳which can cause: dehydration, electrolyte imbalances, chronic constipation & laxative dependency
• Side Effects:
  • abdominal cramps, N/V, D

Antiemetics

• Antiemetics = no vomit
• Mechanism of Action:
  • Target specific neuroreceptors
  • Interact with vomiting center (VC) and chemoreceptor trigger zone (CTZ)

Types of Antiemetics

Anticholinergics

- Block acetylcholine receptors
- Prevent nausea-inducing stimuli
- Example: Scopolamine = Transdermal patch
- Side effects: Seizures, psychosis, drowsiness

Antihistamines

- Also used as Anti-Vertigo
- Block H1 receptors
- Prevent motion sickness
- Example: Meclizine
- Side effects: drowsiness, dry mouth, blurred vision

Dopamine Antagonists

- Block dopamine in CTZ
- Side effects: drowsiness, restlessness, dry mouth, constipation

Prokinetics

- Pro movement => reduce nausea
- Block dopamine and acetylcholine
- Promote motility
- Used post-op
- Contraindicated: with GI hemorrhage, Obstruction or Perforation
- SE= hypertensive Crisis or Seizure, suicidal thoughts

Serotonin Antagonists

- Block serotonin receptors
- May Cause: HA, Constipation, prolonged QTI

• Nursing Considerations:
  • Varied side effects depending on type
  • Monitor for potential interactions

Additional Medications

Phenazopyridine (Pyridium)

• Mechanism of action: Local anesthetic for lining of urinary tract
• Indications: Dysuria
• Nursing Considerations:
  • Is OTC, but higher doses available by rx
  • Is excreted in urine and may cause it to turn orange/red

Desmopressin

• Mechanism of action: Synthetic version of ADH (vasopressin); a selective agonist of V2 receptors in renal collecting duct
  • increase H20 re-absorption & reduce urine production
• Indications: antidiuretic in diabetes insipidus & bedwetting
• Nursing Considerations:
  • Nasal spray & tablet
  • Taken at night for bedwetting
  • Many drug interactions
  • Monitor BP
• May cause hyponatremia, HA, dizziness, restlessness edema, N/V

Tamsulosin (Flomax)

• Mechanism of action: blocks alpha receptors; relaxes muscles in prostate & bladder
• Indications: benign prostatic hyperplasia, kidney stone
• Nursing Considerations:
  • Monitor I & O, daily weight & BP
• Not enough data regarding pregnancy