Zepbound side effect
Mild fatigue affects roughly 5–15% of GLP-1 users, mostly in the first month. It usually traces back to reduced calorie intake rather than the drug itself.
In trial — Zepbound
5.1%
In trial — placebo
1.1%
Severity
mild
Source: SURMOUNT-1 (Jastreboff et al., NEJM 2022)
GLP-1 drugs suppress appetite — if you eat well below your maintenance energy needs you'll feel tired. Adequate protein, electrolytes, and a modest deficit (not extreme) prevent the worst of it.
Timeline
Common during the first 4 weeks of any new dose; resolves as your body adapts to the lower intake.
Call your prescriber if:
Almost always under-eating. The medication suppresses appetite — if you don't deliberately hit protein and calorie targets, you'll feel drained. Aim for 100–120g of protein and at least 1200 kcal even in the deepest restriction phase.
This is general drug information, not medical advice. Talk to a licensed clinician before changing your dose, stopping, or starting any over-the-counter remedy.
Drug-specific guides for the other commonly reported reactions on Zepbound.
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