Contraindications and Cautions for Semaglutide and Tirzepatide

Absolute Contraindications

Personal or family history of medullary thyroid carcinoma (MTC) or multiple endocrine neoplasia type 2 (MEN 2) precludes use of semaglutide and tirzepatide. The American College of Cardiology (ACC) states this as an absolute contraindication for all adult patients. [@1]
Preclinical rodent studies show dose‑ and duration‑dependent thyroid C‑cell tumors, prompting the FDA to issue a black‑box warning for both agents. Evidence is based on animal toxicology data; no human cases have been reported. [@1]
The contraindication applies even when genetic testing for MEN 2 has not been performed. Clinical guidance recommends assuming risk in the absence of confirmed negative testing. [@5]
Pregnancy and breastfeeding are absolute contraindications. Both societies advise avoiding exposure because of potential fetal and neonatal toxicity. [@4]

Severe renal impairment or end‑stage renal disease (ESRD) – semaglutide and tirzepatide may be used only with caution, unlike exenatide and lixisenatide which are contraindicated. The ACC recommends dose adjustment and close monitoring. [@1]
Renal function should be monitored closely at therapy initiation and dose escalation because dehydration from gastrointestinal side effects can precipitate acute kidney injury. (Strength of recommendation: moderate). [@4]

History of pancreatitis – use semaglutide with caution; data are insufficient to confirm safety in patients with prior pancreatitis. ACC advises individualized risk‑benefit assessment. [@1]
Clinically significant gastroparesis – agents are not recommended because they further delay gastric emptying and may worsen symptoms. [@1]
Prior gastric or bariatric surgery – extreme caution is required due to altered anatomy and delayed emptying. [@1]

Diabetic retinopathy – semaglutide has been linked to worsening retinopathy, possibly related to rapid glucose reduction; close ophthalmologic monitoring is advised. [@1]

Nausea, vomiting, diarrhea, and constipation occur in the majority of patients and are dose‑dependent and usually transient. Evidence from large phase 3 trials (ADA) supports this frequency. [@2]

Gallbladder disease – semaglutide increases the risk of cholelithiasis and cholecystitis by >2.6‑fold (95 % CI 1.40–4.82); tirzepatide does not show a significant increase. Data derived from pooled ADA trial analyses. [@2]
Acute pancreatitis – cases have been reported in clinical trials, but causality remains unproven. (Strength of recommendation: low). [@4]
Acute kidney injury – risk is heightened by dehydration secondary to severe gastrointestinal effects. (Strength: moderate). [@4]

Hypoglycemia risk – when combined with insulin or insulin secretagogues (e.g., sulfonylureas, glinides), the risk of hypoglycemia rises; dose reduction of the concomitant agents is required. ACC guidance recommends proactive dose adjustment. [@1]
Oral hormonal contraceptives – switch to non‑oral methods or add a barrier method for 4 weeks after therapy initiation and after each dose escalation because delayed gastric emptying can reduce contraceptive absorption. (Strength: moderate). [@2]
Absorption of narrow‑therapeutic‑index oral drugs (e.g., warfarin) may be slowed due to delayed gastric emptying; clinicians should monitor therapeutic levels. [@1]

Semaglutide – start 0.25 mg subcutaneously once weekly for 4 weeks, then increase to 0.5 mg, then 1.0 mg if needed; maximum 2.4 mg weekly for weight‑management indications. This step‑wise titration reduces gastrointestinal intolerance (JAMA). [@6]
Tirzepatide – start 2.5 mg subcutaneously once weekly; increase after at least 4 weeks at each dose level (e.g., 5 mg, 7.5 mg, up to 15 mg). (Strength: strong). [@6]
Initiating therapy at high doses bypasses the body’s adaptation to delayed gastric emptying and markedly increases gastrointestinal adverse events. (Strength: moderate). [@4]

Do not prescribe semaglutide or tirzepatide to patients with a family history of MTC without first confirming the absence of the contraindication. ACC emphasizes explicit exclusion. [@1]
Do not neglect renal function monitoring in patients with pre‑existing kidney disease or those experiencing severe gastrointestinal symptoms that could cause dehydration. [@4]
Do not combine these agents with insulin or sulfonylureas without first reducing the dose of the insulin‑secretagogue to prevent hypoglycemia. [@1]
Do not use semaglutide or tirzepatide in patients with active or suspected pancreatitis. (Guideline recommendation based on safety concerns). [@1]