Benzamides

Metoclopramide (Maxolon)

Crosses blood-brain barrier

Well-absorbed orally but bioavailability varies widely (30-90%) due to variable first-pass metabolism

Actions

D2 antagonism

Prokinetic effects on stomach

5-HT3 antagonism at high doses

Side-effects

• Hypotension
• Extrapyramidal effects (more common in children and young adults)
• Gynaecomastia, galactorrhoea
• Arrhythmias

Usage

Uraemia, radiation, gastrointestinal disorders, cytotoxic drugs