Evidence-graded answer
Why am I not losing weight on Wegovy?
Most non-responders fall into 4 buckets: dose hasn't reached maintenance (2.4 mg), titration was interrupted, calorie intake creeps to match satiety, or a hormonal/medical confounder (hypothyroid, PCOS-with-insulin-resistance, sleep apnea). Talk to your prescriber if no measurable loss by week 16 at maintenance dose.
Trial data: about 1 in 6 patients lose less than 5% at week 68 (STEP-1) — biological variance is real.
Common fixes: confirm you are at 2.4 mg (not stuck at 1.7), audit calorie intake for 2 weeks (smaller appetite ≠ smaller calories if food choices are calorie-dense), check TSH + fasting insulin, address sleep apnea.
If true non-response is confirmed by week 24 at maintenance, a switch to tirzepatide (Zepbound) is reasonable — head-to-head data favors tirzepatide on weight loss.