DisclosureWe earn commission on partner links; ranking is set by our published methodology — not advertisers.
The first month sets expectations. Most patients experience appetite reduction within days, GI side effects within the first week, and the first real weight loss by week 3-4.
First injection at sub-therapeutic starter dose (Wegovy 0.25 mg, Zepbound 2.5 mg, Mounjaro 2.5 mg). Nausea is the most common side effect: 44% of Wegovy 2.4 mg and 25-29% of Zepbound patients reported it over the full trials (vs 16% and 8% on placebo). Appetite suppression is often noticeable by day 7.
Severe nausea or vomiting requiring medical contact. Signs of dehydration (dark urine, dizziness, headaches). Hypoglycemia symptoms if you are on insulin or sulfonylureas. Injection-site reactions beyond mild redness.
STEP-1 (Wegovy) and SURMOUNT-1 (Zepbound) both showed peak nausea incidence during titration weeks 1-12. Most users adapt; <10% discontinue in the first 8 weeks due to GI effects.
The biggest mistake new users make is treating the first 4 weeks as the steady state. The starter dose is sub-therapeutic. Real weight loss accelerates after week 8. Do not judge efficacy yet.
Editorial summary, not medical advice. Cycling, dose changes, and discontinuation should be coordinated with your prescriber.