Semaglutide

most data

Also seen as: Ozempic, Wegovy, Rybelsus, sema

The Dose Guy’s verdict

Aug 28, 2026
3 sources

The deepest evidence base in the class, and the one with a cardiovascular outcomes trial that actually reduced heart attacks and strokes. Semaglutide works, the GI ride is manageable, and if you can get it through a pharmacy that route beats gray-market anything. On the gray market itself, tirzepatide and retatrutide both outperform it, so semaglutide lands when pharmacy access or the sheer weight of the safety data tips the scale.

Would I take it?Yes, the one your doctor knows.

What it is

Semaglutide is a GLP-1 receptor agonist, one receptor, one job: it mimics the gut hormone that tells your brain you’re full, slows your stomach, and quiets the constant food noise. It was the compound that proved this approach could produce real weight loss in a general population, and it opened the door for everything that followed. Newer compounds stack more receptors on top of the same base: tirzepatide adds GIP, retatrutide adds GIP and glucagon. Semaglutide is the foundation they all built on. It also exists as a daily oral tablet, but for weight loss the weekly injectable is what the trials tested and what most people run.

What the research shows

No compound in the weight-loss space has been tested in more people, across more endpoints, over more years:

STEP 1 at 68 weeks: mean weight loss of 14.9% with semaglutide 2.4 mg weekly versus 2.4% with placebo, and 50.5% of the semaglutide group lost at least 15%.NEJM 2021 · phase 3 · n=1961

SELECT, the cardiovascular outcomes trial: major adverse cardiovascular events in 6.5% with semaglutide versus 8.0% with placebo, a 20% relative reduction over a mean 39.8 months.NEJM 2023 · outcomes · n=17604

STEP 5 at 104 weeks: 15.2% weight loss sustained over two full years, versus 2.6% with placebo.Nat Med 2022 · phase 3 · n=304

Realistic protocols

Same approach as the rest of the class: dose to your hunger, not to a schedule. Start at 0.25 mg once a week, subcutaneously. If appetite is quiet and the weight is coming off, there is no reason to chase a higher dose. Push up only when hunger returns, and give each step about a month before judging it.

If you have pharmacy access, use it. The gray market is where tirzepatide and retatrutide pull ahead on raw effect, so semaglutide’s advantage is the prescription path.

Drinking on semaglutide is a common early surprise. The slowed stomach means alcohol hits harder and nausea comes faster. Most people end up drinking less without deciding to. And the same rule as every compound in this class: keep protein high and keep lifting, because the cut will take muscle if you let it.

Start0.25 mg/wkSub-q, once weekly. Four weeks here, minimum.

Holdyour doseIf hunger is quiet and weight is moving, stay.

Raisenext step0.5, 1, 1.7, 2.4 mg. Only when appetite returns. A month each.

Ceiling2.4 mg/wkApproved max. Not a target, just the top of the map.

Side effects

The GI profile is familiar across the class, and most events are front-loaded:

commonNausea and diarrhea, mostly during the first weeks on each new dose, typically mild to moderate and transient.

monitorIn diabetics, semaglutide has flagged more retinopathy complications than placebo. If you have diabetes, get a baseline eye exam before starting.

anecdotalMuscle loss on a fast cut, reported widely. The protein and lifting advice in Protocols is not optional.

monitorPancreatitis has shown up at a low rate across the incretin class. Severe upper-belly pain that bores through to your back is a stop-everything.