Plateau

A plateau is the stretch where the scale stops moving even though nothing about your routine has changed. It is the most common reason people conclude a GLP-1 has stopped working, and usually the conclusion is wrong.

Weight loss on these drugs is never linear. It is fastest during dose escalation and slows as you approach a new equilibrium, because a lighter body burns fewer calories at rest and at the same activity level. A plateau at a lower weight is your metabolism balancing at that weight — not evidence the medication has failed.

The trial data is unusually clear on what continued treatment does. In SURMOUNT-4, participants lost a mean 20.9% over a 36-week lead-in, then were randomized; those who stayed on tirzepatide lost a further 5.5% over the next year, while those switched to placebo gained 14.0%. STEP 4 showed the same shape with semaglutide: after a 20-week run-in averaging 10.6% loss, continuing produced another 7.9% while switching to placebo produced a 6.9% gain. Plateaus in these trials were waypoints, not endpoints.

The confusion is treating a plateau as a verdict when it is a checklist. Several things look identical on the scale: you have not reached your maintenance dose yet; calorie intake has drifted upward as nausea faded; you are losing fat while gaining muscle from new training; you are retaining water after a salty week. Only one of those calls for a dose conversation, and none of them is failure.

A useful rule before acting: give it four to six weeks, track something other than weight — waist circumference, how clothes fit, a body-composition scan — and log what you are actually eating rather than what you think you are. Then ask your clinician whether a dose increase is appropriate, whether there is room left on the ladder, and whether a genuine non-response warrants switching. Our plateau decision tree and week-12 checkpoint guide work through it.