Rimonabant
The first CB1 receptor antagonist for weight loss — withdrawn due to psychiatric side effects but historically significant.
Plain English
Patient-Friendly Explanation
Rimonabant was a weight-loss medication that worked by blocking cannabinoid receptors in the brain — the same receptors activated by appetite-stimulating compounds in the body. It was the first in a new class of anti-obesity drugs but was eventually withdrawn from the market.
Medical
Clinical Definition
Rimonabant is a selective cannabinoid type-1 (CB1) receptor antagonist that was the first drug in the endocannabinoid blocker class. By inhibiting CB1 receptors in the central nervous system and peripheral tissues, it reduced food intake, decreased lipogenesis, and improved cardiometabolic parameters — producing 4.7-6.3 kg weight loss in clinical trials. It was withdrawn globally in 2008 due to increased risk of psychiatric adverse events including depression, anxiety, and suicidal ideation.
Key Insight
Why It Matters
Although rimonabant is no longer available, its development taught researchers valuable lessons about the endocannabinoid system's role in weight regulation. Current research continues to explore safer CB1-targeting approaches for obesity treatment. At Accord Medical, we stay informed about emerging therapies to offer patients the most current evidence-based care.
Sources
Reviewed against standard medical references.
Medically reviewed by
Family Physician & Registered Acupuncturist, Accord Medical Clinic. MBBS (NUS), Graduate Diploma in Family Medicine (NUS), Graduate Diploma in Acupuncture (Singapore College of TCM).
Last reviewed: August 2026
This page is general health education, not medical advice. Whether any treatment is appropriate for you is a decision made in consultation after assessment.