Tesamorelin is a synthetic hormone that reduces excessive abdominal fat in adults with HIV and lipodystrophy by mimicking growth hormone-releasing hormone (GHRH) to stimulate growth hormone (GH) production. It is administered as a daily subcutaneous injection and is not a weight loss drug but specifically targets fat accumulation associated with HIV-related lipodystrophy. Potential side effects can include temporary bloating, joint stiffness, and increased appetite, and it may affect blood sugar levels.