Antidiarrheal and Laxatives Flashcards
What is the difference between acute and chronic diarrhea?
Acute
- Sudden onset, lasts 3 days to 2 weeks
- Resolves with no other complications
Chronic
- More than 3 weeks
- Fever, loss of appetite, nausea, vomiting, weight loss, and chronic weakness
What are the different causes of acute and chronic diarrhea?
Acute
- Microbial
- Drug induced
- Nutritional
Chronic
- Tumours
- Diabetes
- Hormonal (hyperthyroidism, addison’s disease(
- IBS
How are opioids used to treat diarrhea?
Loperamide (imodium)
- Decreased bowel motility and relieves rectal spasms
- Increases transit time through bowel = increased absorption
What are the adverse effects of opioids?
- Drowsiness, dizziness, sedation, lethargy
- N/V, anorexia, constipation
- Respiratory depression
- Bradycardia, palpitations, hypotension
- Urinary retention
- Flushing, rash urticaria
What is an example of an adsorbent and what’re the adverse effects?
Bismuth subsalicylate (Pepto Bismol) - Can also be used for relief of stomach acid symptoms
Adverse effects
- Constipation
- Dark stools and tongue
- Metallic taste, blue gums
- Potential confusion and twitching with renal impairment
How to antidiarrheal agents impact the absorption of other drugs?
Adsorbents decrease the absorption of drugs like digoxin, clindamycin, quinidine, and hypoglycemic agents
Who should you not give bismuth subsalicylate to?
Children younger than 16 or teenagers with viral infections (chicken pox)
- Can cause Reye’s syndrome
How to anticholinergics (antispasmodic) drugs function and what’s an example?
*Atropine
- Decrease intestinal muscle tone and peristalsis of GI
- Slows movement of fecal matter through GI tract
What are typical anticholinergic adverse effects?
- Headache, dizziness, confusion, anxiety
- Blurred vision, photophobia, increased intraocular pressure
- Dry mouth, dry skin, rash, flushing
- CV (eg tachycardia)
- Constipation
- Urinary retention, hesitancy, impotence
Should not be administered with patients with history of
- Glaucoma
- BPH, urinary retention, recent bladder surgery
- Cardiac problems
- Myasthenia gravis
What are some common complications of constipation?
Hemorrhoids Anal fissures Fecal impaction Rectal prolapse "Lazy bowel"
When should you not use laxatives?
If there’s a bowel obstruction
When not needed. It can lead to atonic colon “lazy bowel” and requirement of more laxatives (dependency)
What is bulk forming and what is an example?
*Methylcellulose (citrucel)
High fibre substances (non-digestible material)
Absorbs water to increase bulk
Distended bowel to initiate reflex bowel activity
What are fecal softeners and what is an example?
*Docusate sodium (Surfak)
Stool softeners and lubricants
Promotes more water and fat in the stools
Lubricates the fecal material and intestinal walls
What are hyperosmotic laxatives ad what is an example?
*Lactulose
Increase fecal water content
- Bowel distention, increased peristalsis, and evacuation
What are saline laxatives and what is an example?
Magnesium hydroxide
Increase osmotic pressure within the intestinal tract, causing more water to enter the intestines
Bowel distention, increased peristalsis and evacuation
