Pharmacology of Gastrointestinal Medications

Antiacids

• Neutralize stomach acidity
• Decrease pepsin activity
• Increase gastric pH

Bulk-forming Laxatives

• Soften stools
• Increase stool bulk

H2 Receptor Antagonist

• Generic name ends in "-tidine"

Non-pharmacological treatments of constipation

• Increase fiber intake
• Increase hydration
• Increase exercise

Appropriate Use of Laxatives

• Short term use
• Avoid long term use
• Consult a physician for long-term treatment

Peptic Ulcer Disease (PUD)

• Characterised by erosions in the lining of the gastrointestinal tract (stomach, duodenum)

Gastroesophageal Reflux Disease (GERD)

• Occurs when stomach acid flows back into the esophagus
• Can cause heartburn
• May be linked to lifestyle changes, smoking, alcohol
• Can cause esophagitis (inflammation of the esophagus)

Promethazine

• Antiemetic
• Used to treat nausea and vomiting

Psyllium Mucilliod

• Bulk-forming laxative

### Metclopramide(Reglan)

• Prokinetic agent
• Increases the speed of gastric emptying
• Treats gastroparesis

### Ompeprazole

• Proton Pump Inhibior(PPI)
• Blocks the production of stomach acid
• Generic name ends in "-prazole"

### Sucralfate

• Mucosal Protectant
• Forms a protective layer over ulcerated areas

### Scopolamine Patch

• Antiemetics
• Used to prevent post-operative nausea and vomiting

### Diphenoxylate with Atropine

• Antidiarrheal
• Slows down bowel contractions
• Reduces diarrhea and cramping

Loperimide

• Antidiarrheal
• Slows down bowel contractions
• Decreases stool frequency

Misoprostol

• Prostaglandin E Analog
• Protects the stomach lining
• Often used to prevent PUD in patients taking NSAIDs

### Bismuth Subsalicylate

• Binds to bacteria
• Protects tissue

Ondansetron

• Antiemetics
• Prevents and treats nausea and vomiting

Bisacodyl

• Stimulant laxative
• Works through the stimulation of the intestines

Alosterone

• 5-Aminsosalicylates
• Used to treat inflammatory bowel diseases

Lactulose

• Osmotic laxative
• Increases the volume of fluid in the intestines
• Promotes bowel movement

Magnesium Hydroxide/Citrate

• Osmotic Diuretic
• Draws water into the colon
• Promotes bowel movement

Ranitidine

• H2 Receptor Antagonist
• Blocks the effects of histamine on stomach cells
• Reduces stomach acid production