Prescription Weight-Loss Medications vs Supplements: What’s the Difference?

Prescription weight-loss medications are clinically tested treatments that must be prescribed by a qualified healthcare professional. They are regulated medicines, meaning they must meet strict standards for safety, quality, and effectiveness.

Two of the most widely discussed prescription weight-loss medications today are Mounjaro (tirzepatide) and Wegovy (semaglutide).

Mounjaro (tirzepatide)

Mounjaro works by activating two hormone receptors involved in appetite and blood sugar regulation:

GLP-1 (glucagon-like peptide-1)

GIP (glucose-dependent insulinotropic polypeptide)

Together, these hormones:

Reduce appetite

Increase feelings of fullness

Slow stomach emptying

Improve blood sugar control

Wegovy (semaglutide)

Wegovy activates the GLP-1 receptor only, but in a higher dose than some diabetes treatments. It works by:

Suppressing appetite

Reducing food cravings

Helping people feel full sooner and for longer

Both medications are taken as once-weekly injections and are prescribed as part of a medically supervised treatment plan.

What Are Weight-Loss Supplements?

Weight-loss supplements are products sold without a prescription. They are typically marketed as:

Fat burners

Appetite suppressants

Metabolism boosters

Detox or cleansing products

Common ingredients include:

Caffeine

Green tea extract

Garcinia cambogia

Fibre blends

Herbal extracts

Unlike prescription medications, supplements are not required to prove effectiveness before being sold.