• HIV/AIDS-related weight loss: Moderate. Dronabinol (prescription THC) is FDA-approved for this use.

• Cancer-related weight loss: Not established. Trials have not shown reliable gains in weight or muscle.

Good to know: THC can increase appetite for a few hours after a dose. A dietitian should be part of care for any unplanned weight loss.

What to ask for: A THC-dominant oral product taken before lunch and dinner , the way dronabinol is prescribed for appetite. CBD-only products do not stimulate appetite.