Generic Name of Amitiza
The generic name of Amitiza is lubiprostone 1.
Drug Classification and Mechanism
Lubiprostone is a chloride channel activator (specifically activating ClC-2 channels) that is available as an oral soft gelatin capsule in two strengths: 8 mcg (pink capsules) and 24 mcg (orange capsules) 1. The chemical name is (–)-7-[(2R,4aR,5R,7aR)-2-(1-difluoropentyl)-2-hydroxy-6-oxooctahydrocyclopenta[b]pyran-5-yl]heptanoic acid, with molecular formula C20H32F2O5 1.
FDA-Approved Indications
According to the FDA drug label, lubiprostone (Amitiza) is approved for:
- Chronic idiopathic constipation (CIC): 24 mcg twice daily 1
- Irritable bowel syndrome with constipation (IBS-C): 8 mcg twice daily (approved for women only) 1
- Opioid-induced constipation (OIC): dosing varies based on indication 1
Clinical Context
The 2023 AGA-ACG guidelines classify lubiprostone as an intestinal secretagogue and suggest its use in adults with CIC who do not respond to over-the-counter agents (conditional recommendation, low certainty of evidence) 2. The mechanism involves enhancing chloride-rich intestinal fluid secretion without altering serum sodium and potassium concentrations, thereby increasing intestinal motility and facilitating stool passage 2.