Semaglutide: what it is, what it costs, and who sells it

Semaglutide is a synthetic peptide engineered to activate the GLP-1 hormone receptor, the same gut-hormone signal the body releases after eating. FDA has approved several branded products built on it — Wegovy (injection, for chronic weight management), Ozempic (injection, for type 2 diabetes), and a newer Wegovy tablet — confirmed directly against FDA's own Drugs@FDA record, which lists Wegovy's marketing status as “Prescription.”

A compounded semaglutide product is a different thing: a pharmacy-prepared version made under the same narrow federal exemption (21 U.S.C. §353a) tirzepatide uses, legal to sell in volume only while a reference brand stays in an FDA-declared shortage. It is not a generic and not independently reviewed by FDA the way the branded pens are — and it is the product almost every telehealth provider on the board below actually sells.

Semaglutide activates the GLP-1 receptor alone — one target, versus tirzepatide's two. That single mechanism slows gastric emptying, boosts insulin release when blood sugar is high, and reduces appetite. STEP 1, the trial that established semaglutide's 2.4 mg weight-management dose, randomized 1,961 adults to semaglutide or placebo for 68 weeks and reported -14.9% body weight versus -2.4% for placebo. In the one trial that has put semaglutide and tirzepatide head to head, semaglutide came in second — read the full comparison, including why that doesn't make it the weaker choice for everyone, in our full tirzepatide-vs-semaglutide review.

The same compounding rule that governs tirzepatide applies to semaglutide: a pharmacy may compound it because it is the active ingredient in an FDA-approved drug, and may sell it in volume only while the reference brand remains in an FDA-declared shortage. Semaglutide's own shortage-resolution timeline runs roughly two months behind tirzepatide's, independently confirmed against fda.gov rather than assumed to track it exactly.

For the complete regulatory timeline and every provider's own pharmacy-sourcing disclosure, see is compounded semaglutide still legal? and what compounded semaglutide actually is, both read directly off the statute and FDA's own guidance.

The dominant signal in semaglutide's own trial data is the same drug-class pattern tirzepatide shows: gastrointestinal. In STEP 1, nausea and diarrhea were the most common adverse events reported, and the trial's own results describe them as “typically transient and mild-to-moderate in severity” — which is what the label's four-week dose-escalation steps exist to reduce, not eliminate.

This site does not yet publish a standalone semaglutide side-effects review the way it does for tirzepatide — for the fullest picture available today, including the exact escalation-pause language FDA's label uses and the missed-dose rule, see our complete semaglutide dosing reference. None of this is a recommendation for or against starting semaglutide — talk to a licensed clinician about your own situation.