How long does it take for a GLP-1 to work?

What changes in the first two weeks?

The earliest signals are about appetite, not weight. Within days to two weeks, most people notice meals ending sooner, snacks losing their pull, and the background chatter about food quieting down. Some feel it after the very first dose; for others it builds across the first weeks.

The scale usually moves only modestly in this window, often 1 to 2% of body weight, and some of that is water and digestion rather than fat. The starting dose is deliberately small; its job is tolerance, not results.

What happens between months one and three?

Doses step up on a schedule (details in our titration explainer), and each step usually deepens the appetite effect. This is where steady weekly loss typically establishes itself. It is also where side effects cluster, in the days after each increase; the nausea guide covers managing them.

By the end of month three, most people who will respond well have clear evidence of it: a downward trend line, smaller default portions, and a routine that has reorganized around the medication.

When does weight loss peak and flatten?

In the major trials, average weight loss accumulated through roughly the first year, then flattened into maintenance. That flattening is physiology, not failure: a smaller body needs fewer calories, and the deficit narrows as you shrink. Our plateau guide covers reading a stall honestly.

What if nothing seems to be happening?

First, check the instrument. A weekly trend line, waist measurements, and honest food logs detect progress the bathroom scale hides. Second, remember dose context: many people feel little at the starter dose and respond clearly two steps later. If you are months in at a therapeutic dose with a truly flat trend and unchanged appetite, that is a prescriber conversation, and it goes better with records than with impressions. DoseLog keeps dose days, appetite notes, and the weight trend on one line for exactly that conversation.