Adverse Effects and Red Flags in Zepbound (Tirzepatide) Use

Common Adverse Effects

Gastrointestinal side effects, including nausea, vomiting, diarrhea, and esophageal reflux, are the most common adverse reactions with tirzepatide, typically most pronounced during dose escalation and may diminish over time 1, 2
Injection site reactions can occur with subcutaneous administration of tirzepatide 2, 3
Elevated heart rate has been observed in patients taking tirzepatide 2, 3
Hypoglycemia risk is present but generally lower than with insulin therapy, with tirzepatide probably reducing severe hypoglycemia compared to insulin (RR, 0.21 [CI, 0.11 to 0.38]) 4, 5

Pancreatitis has been reported in clinical trials, and treatment should be discontinued if pancreatitis is suspected 2, 3
Gallbladder disease may be caused by tirzepatide, particularly with rapid weight loss, and patients should be monitored for cholelithiasis (gallstones) and gallstone-related complications 2, 3
Gastrointestinal obstruction, including severe constipation, small bowel obstruction, and ileus progression, has been reported, and patients with pre-existing gastrointestinal disease require careful monitoring 2, 3
Acute kidney injury is a potential risk when initiating or increasing the dose in people with kidney disease 2, 3
Medication absorption issues may occur, as tirzepatide may delay absorption of oral medications, particularly concerning for medications with a narrow therapeutic index like warfarin 2, 3
Hormonal contraception effectiveness may be reduced, and women using oral hormonal contraception should use or add a non-oral contraception method for 4 weeks after initiation and dose escalations 3
Thyroid C-cell tumors have been observed in rodents, and the FDA label includes a black box warning, although human relevance has not been determined 2, 3

Tirzepatide may reduce serious adverse events compared with insulin (RR, 0.80 [CI, 0.67 to 0.96]) 4, 5
GLP-1 agonists probably reduce serious adverse events compared with tirzepatide (RR, 0.57 [CI, 0.34 to 0.96]), suggesting tirzepatide may have a higher rate of certain adverse events than GLP-1 agonists alone 4, 5

Gradual dose titration is essential to minimize gastrointestinal side effects 2
Regular monitoring for signs of pancreatitis, such as severe abdominal pain, sometimes radiating to the back, with or without vomiting, is necessary 2, 3
Assessing for gallbladder disease in patients reporting right upper quadrant pain is recommended 3
Monitoring renal function, particularly when initiating therapy or increasing doses in patients with pre-existing kidney disease, is crucial 2, 3
Considering vitamin B12 monitoring in long-term use is advised, as this has been identified as a concern with other agents affecting incretin pathways 6
Evaluating medication regimens for potential drug interactions, particularly for medications with narrow therapeutic indices, is necessary 3

Patients with a history of gastrointestinal disorders should be monitored closely due to the high incidence of GI side effects 2, 3
Patients with a personal or family history of medullary thyroid carcinoma or Multiple Endocrine Neoplasia syndrome type 2 should avoid tirzepatide use due to the black box warning regarding thyroid C-cell tumors 3
Discontinuing treatment if severe adverse reactions occur or if pancreatitis is suspected is recommended 2, 3