Chapter 51 Bowel disorder drugs Flashcards
(116 cards)
The key symptoms of gastrointestinal (GI) disease are?
abdominal pain, nausea and/or vomiting, and diarrhea.
Diarrhea is a leading cause of morbidity and mortality in?
underdeveloped countries
Diarrhea is defined as the passage of?
stools with abnormally increased frequency, fluidity, and weight, or increased stool water excretion.
Acute diarrhea refers to diarrhea of sudden onset in a previously healthy individual. It lasts from 3 days to 2 weeks and is self-limiting, resolving without sequelae. Causes of acute diarrhea include?
drugs, bacteria, viruses, nutritional factors, and protozoa.
Chronic diarrhea lasts for longer than 3 to 4 weeks and is associated with recurrent passage of diarrheal stools, possible fever, nausea, vomiting, weight reduction, and chronic weakness. Causes of chronic diarrhea include?
tumors, acquired immunodeficiency syndrome, diabetes mellitus, hyperthyroidism, Addison’s disease, and irritable bowel syndrome (IBS).
Drugs used to treat diarrhea include?
adsorbents, anticholinergics, opiates, and probiotics.
Treatment is aimed at stopping?
stool frequency, alleviating abdominal cramps, replenishing fluids and electrolytes, and ending weight loss and nutritional deficits from malabsorption.
Fluid and electrolyte replacement is vital while a patient is experiencing diarrhea.
.
Patients with diarrhea associated with a bacterial or parasitic infection must NOT use?
Antidiarrheal drugs, because this will cause the organism to stay in the body longer and will prolong recover
Drugs used to treat diarrhea are called antidiarrheal drugs. Based on the specific mechanism of action, they are divided into different groups:
adsorbents, antimotility drugs, and probiotics (also known as intestinal flora modifiers and bacterial replacement drugs).
Adsorbents mechanism of action
- Coat the walls of the gastrointestinal (GI) tract
- Bind to the causative bacteria or toxin, which is then eliminated through the stool
- Examples: bismuth subsalicylate (Pepto-Bismol), activated charcoal, and antilipemic drugs colestipol and cholestyramine
Antimotility drugs: anticholinergics Mechanism of action
- Decrease intestinal muscle tone and peristalsis of GI tract
- Result: slows the movement of fecal matter through the GI tract
- Example: belladonna alkaloids
Antimotility drugs: opiates mechanism of action
- Decrease bowel motility and reduce pain by relief of rectal spasms
- Decrease transit time through the bowel, allowing more time for water and electrolytes to be absorbed
- Examples: paregoric, opium tincture, codeine, over-the-counter (OTC) loperamide, diphenoxylate
Antimotility drugs: anticholinergics mechanism of action
- Slow peristalsis by reducing the rhythmic contractions and smooth muscle tone of the GI tract
- Drying effect
- Reduce gastric secretions
- Used in combination with adsorbents and opiates
Activated charcoal is not only helpful in coating the walls of the GI tract and absorbing bacteria but also is useful in cases of?
Overdose because of its drug-binding properties
Probiotics mechanism of action
- Also known as intestinal flora modifiers and bacterial replacement drugs
- Bacterial cultures of Lactobacillus organisms work by:
- Supplying missing bacteria to the GI tract
- Suppressing the growth of diarrhea-causing bacteria
- Example: Lactobacillus acidophilus (Bacid)
The primary action of opiates in diarrhea tx is to?
Reduce bowel motility. A secondary effect that makes opiates beneficial in the Tx of diarrhea is reduction of pain associated with diarrhea by relief of rectal spasms
-Because they decrease the transit time of food through the GI tract, they permit longer contact of the intestinal contents with the absorptive surface of the bowel, which increases absorption of water, electrolytes, and other nutrients from the bowel and reduces stool frequency and net volume
Antidiarrheal indications
1) Adsorbents: milder cases
2) Anticholinergics and opiates: more severe cases
3) Probiotics: antibiotic-induced diarrhea
Antidiarrheal contraindications
- known drug allergy
- any major acute GI condition (intestinal obstruction, colitis)
Antidiarrheal adverse effects for absorbents
- Increased bleeding time
- Constipation, dark stools
- Confusion
- Tinnitus
- Metallic taste
- Blue gums
Antidiarrheal adverse effects for anticholinergics
- Urinary retention, impotence
- Headache, dizziness, confusion, anxiety, drowsiness,
- Dry skin, flushing
- Blurred vision
- Hypotension, bradycardia
Antidiarrheal adverse effects for Opiates
- Drowsiness, dizziness, lethargy
- Nausea, vomiting, constipation
- Respiratory depression
- Hypotension
- Urinary retention
- Flushing
Adsorbents interactions
- Adsorbents decrease the absorption of many drugs, including digoxin, quinidine, and hypoglycemic drugs.
- Adsorbents cause increased bleeding time and bruising when given with anticoagulants (warfarin).
- Toxic effects of methotrexate are more likely when given with adsorbents.
The primary action of opiates in diarrhea treatment is to?
reduce bowel motility and thus permit longer contact of intestinal contents with the absorptive surface of the bowel. A secondary effect that makes opiates beneficial in the treatment of diarrhea is reduction of the pain associated with diarrhea by relief of rectal spasms.