2016 Lower GI Pharmacology

PROKINETIC AGENTS dramatically increase motility throughout the entire GI tract (not just the colon).  They are particularly useful in the treatment of diabetic gastroparesis.  CISAPRIDE and other 5HT4 antagonists have severe cardiac side effects that restrict their use.

• act via the enteric nervous system


• pharmacologically, considered a distinctly different class of drugs from laxatives and cathartics, which tend to act more indirectly, and to influence only the large intestine


• also increase lower esophageal sphincter pressure

Types

• Dopamine D₂ receptor antagonists: METOCLOPRAMIDE, DOMPERIDONE
  • most widely used


• Macrolide antibiotics: esp. ERYTHROMYCIN


• 5HT₄ agonist: CISAPRIDE
  • restricted (compassionate use only)

Primary Use

• impaired gastric emptying - primarily due to postsurgical disorders (vagotomy) and diabetic gastroparesis

Other Uses

• GERD and non-ulcer related dyspepsia (not so much since the advent of PPIs) due to actions on LES pressure

• Prokinetics
• Antidiarrheals
• Laxatives/Cathartics
  • Use & Abuse
• IBS Treatments