Zepbound (Tirzepatide) and Vomiting: When to Call the Doctor

How common is vomiting on Zepbound?

In the two pooled placebo-controlled weight-management trials in the Zepbound label (SURMOUNT-1 and SURMOUNT-2, up to 72 weeks, 2,519 adults treated with Zepbound), vomiting was reported by 8% of patients on 5 mg, 11% on 10 mg and 13% on 15 mg, against 2% on placebo [1]. Nausea was more common at every dose (25%, 29% and 28% vs 8%), and so was diarrhea (19%, 21% and 23% vs 8%) [1].

Vomiting is part of a broader gastrointestinal picture. Any gastrointestinal adverse reaction was reported by 56% of patients at every Zepbound dose, compared with 30% on placebo [1]. Treatment was stopped for gastrointestinal reasons by 1.9% of patients on 5 mg, 3.3% on 10 mg and 4.3% on 15 mg, against 0.5% on placebo [1]. Severe gastrointestinal reactions were reported in 1.7%, 2.5% and 3.1% respectively, against 1% on placebo, and the label says Zepbound is not recommended in patients with severe gastroparesis [1]. The label does not break the severe reactions down by specific symptom such as vomiting.

Gastric emptying and dose timing

Tirzepatide is a dual GIP and GLP-1 receptor agonist given as a once-weekly subcutaneous injection [1]. The label states that it delays gastric emptying, that this delay is largest after the first dose and that it diminishes over time [1]. It also states that the majority of nausea, vomiting and diarrhea events occurred during dose escalation and decreased over time [1].

Zepbound starts at 2.5 mg once weekly for 4 weeks. The 2.5 mg dose is for initiation only and is not approved as a maintenance dose [1]. After 4 weeks the dose goes to 5 mg, and it can then be raised in 2.5 mg increments after at least 4 weeks on the current dose, depending on response and tolerability [1]. Maintenance dosing is 5, 10 or 15 mg once weekly for weight reduction, and 10 or 15 mg for obstructive sleep apnea, with a maximum of 15 mg weekly [1]. The label describes this escalation schedule as a way to reduce the risk of gastrointestinal adverse reactions, and says to consider a lower maintenance dose if a maintenance dose is not tolerated [1].

What the label warns about

Dehydration and kidney injury. The label carries a warning about acute kidney injury from volume depletion. It notes postmarketing reports of acute kidney injury, in some cases requiring hemodialysis, in patients treated with GLP-1 receptor agonists or Zepbound, with most events occurring in patients who had gastrointestinal reactions leading to dehydration, such as nausea, vomiting or diarrhea [1]. It says to monitor renal function in patients reporting reactions that could lead to volume depletion, especially during dose initiation and escalation [1].

Severe or persistent abdominal pain. The label warns about acute pancreatitis, including fatal and non-fatal hemorrhagic or necrotizing pancreatitis, in patients treated with GLP-1 receptor agonists or Zepbound. It lists persistent or severe abdominal pain, sometimes radiating to the back, which may or may not come with nausea or vomiting, as signs and symptoms [1]. The label says to discontinue Zepbound if pancreatitis is suspected and to start appropriate management [1]. In the pooled weight-management trials, 0.2% of Zepbound-treated patients had adjudication-confirmed acute pancreatitis, the same as placebo (0.2%); in the pooled sleep apnea studies the rate was 0.84 patients per 100 years on Zepbound and 0 on placebo [1].

Suspected gallbladder inflammation. Zepbound has been associated with acute gallbladder disease. In the pooled trials, cholelithiasis occurred in 1.1% of Zepbound-treated patients versus 1% on placebo, cholecystitis in 0.7% versus 0.2%, and cholecystectomy in 0.2% versus none on placebo [1]. The label says that if cholecystitis is suspected, gallbladder studies and appropriate clinical follow-up are indicated [1].

Signs of a serious allergic reaction. Serious hypersensitivity reactions including anaphylaxis and angioedema have been reported after marketing [1]. In the pooled trials, 0.1% of Zepbound-treated patients had a severe hypersensitivity reaction, versus none on placebo [1]. The label says to advise patients to promptly seek medical attention and discontinue Zepbound if a serious hypersensitivity reaction is suspected [1].

Low blood pressure. Hypotension was reported in 1.6% of Zepbound-treated patients versus 0.1% on placebo, and it was more frequent in patients also taking antihypertensive medication (2.2% versus 1.2%) [1]. The label adds that hypotension also occurred in association with gastrointestinal events [1].

How long does vomiting last?

The label's description is directional rather than timed: most nausea, vomiting and diarrhea occurred during dose escalation and decreased over time [1]. It gives no typical duration.