Who should not take semaglutide or tirzepatide?
The Wegovy and Zepbound labels say these drugs must not be used by anyone with a personal or family history of medullary thyroid carcinoma, by anyone with multiple endocrine neoplasia syndrome type 2, or by anyone with a known serious allergy to the drug or its ingredients. The labels also tell patients to stop if pregnancy occurs, and they warn about pancreatitis, gallbladder disease, low blood sugar with insulin or sulfonylureas, kidney injury from dehydration, and diabetic retinopathy. A telehealth intake should ask about each of these. Tell your clinician your full history before you start.
Answer dated October 16, 2026; reviewed by Dr. Jonathan Snipes, MD and Kim Callender, NP (FNP-BC).Well-tolerated by most but specific contraindications and cautions matter.
Label contraindications
Personal/family history of MTC
Class boxed warning based on rodent studies. The labels contraindicate use with a personal or family history of medullary thyroid carcinoma. Human evidence is limited but warning is regulatory standard.
MEN-2
Predisposes to MTC. Same contraindication.
Known serious hypersensitivity
Anaphylaxis or angioedema with prior GLP-1 RA therapy, or a serious reaction to any ingredient.
Pregnancy (label instruction)
Pregnancy is not listed among the label contraindications, but the labels say these drugs may cause fetal harm and must be stopped when pregnancy is recognized. The Wegovy label says to stop at least 2 months before a planned pregnancy. Zepbound and Foundayo labels advise a non-oral or backup contraceptive for 4 weeks (Zepbound) or 30 days (Foundayo) after starting and after each dose increase, because they can make birth-control pills less reliable.
Strong cautions
History of pancreatitis
Class label warns of pancreatitis. Prior pancreatitis can be considered case-by-case with informed consent. Acute pancreatitis during therapy = stop, evaluate.
Severe GI disease
Pre-existing gastroparesis is relative contraindication. Active IBD flare warrants caution.
Severe hepatic impairment
Limited safety data in Child-Pugh C cirrhosis.
Severe renal impairment
The semaglutide and tirzepatide labels give no dose adjustment for kidney impairment. FLOW studied semaglutide 1 mg in chronic kidney disease, but dehydration from GI side effects can precipitate AKI.
Active eating disorder
Active anorexia, bulimia, or severe binge eating disorder requires specialized care; GLP-1 generally not appropriate during active symptoms.
Extra monitoring
- Diabetic retinopathy — rapid A1c reduction can transiently worsen it. The labels (Zepbound and Mounjaro revised August 2026) say patients with a history of diabetic retinopathy should be monitored for progression. Ophthalmology coordination if proliferative disease.
- Severe HF with low EF — limited trial data; STEP-HFpEF applies to HFpEF.
- Depression or prior suicidality — in January 2026 FDA asked to remove suicidal behavior and ideation language from the Wegovy, Zepbound and Saxenda labels. Monitor mood as part of routine care; don't withhold reflexively.
- Cholelithiasis history — rapid weight loss raises gallstone risk; monitor for biliary symptoms.
Age
- Children <12: not approved
- Adolescents 12+: Wegovy and Saxenda approved
- Elderly: no upper age limit. Watch dehydration/AKI; monitor sarcopenia.