Strong human trialsFDA approved as Mounjaro +1

Tirzepatide side effects

Also known as: LY3298176 · Mounjaro · Zepbound · Tirz · TZ · TRZ · GLP-2TZ · GLP-2 Tirz · GLP-2 tirzepatide

Updated Oct 24, 202639 sources

17 side effects reported for Tirzepatide: 7 from studies and labels, 10 from users and guides. 12 come with the ways people manage them.

Tirzepatide overview

Side effects reported in studies and labels

Rates as each trial or label states them. A rate from one trial does not carry over to research-grade vials or other doses.

From trials and regulators7

Clinical studies and regulatory documents.

Injection site reactions
6%, 8% and 8% at 5, 10 and 15 mg vs 2% on placebo (SURMOUNT-1 and -2 pooled)
How people manage it
- Rotate between the abdomen, thigh and upper arm.
Dizziness
4%, 5% and 4% at 5, 10 and 15 mg vs 2% on placebo (SURMOUNT-1 and -2 pooled)
Thyroid C-cell tumors
Boxed warning on the label, based on tumors seen in rats
Pancreatitis
Listed in the label warnings
Gallbladder disease
Listed in the label warnings
Kidney injury from dehydration
Listed in the label warnings; linked to fluid loss from GI side effects
How people manage it
- Keep fluids up; the label warns that dehydration from vomiting or diarrhea can hurt the kidneys.
Aspiration risk under anesthesia or sedation
Listed in the label warnings

Side effects users and guides report

What people post and what dosing guides list. These are reports, not measured rates.

From users and guides10

Community reports, competitor and vendor guides, media.

Nausea
25%, 29% and 28% at 5, 10 and 15 mg vs 8% on placebo (SURMOUNT-1 and -2). Diabetes trials: 12%, 15% and 18% vs 4% (SURPASS-1 and -5).
How people manage it
- Eat smaller, lighter meals, especially in the evening.
- Slow the titration or stay on the current dose step longer until GI effects settle.
Diarrhea
19%, 21% and 23% at 5, 10 and 15 mg vs 8% on placebo (SURMOUNT-1 and -2). Diabetes trials: 12%, 13% and 17% vs 9% (SURPASS-1 and -5).
How people manage it
- Keep fluids up; the label warns that dehydration from vomiting or diarrhea can hurt the kidneys.
- Slow the titration or stay on the current dose step longer until GI effects settle.
Vomiting
8%, 11% and 13% at 5, 10 and 15 mg vs 2% on placebo (SURMOUNT-1 and -2). Diabetes trials: 5%, 5% and 9% vs 2% (SURPASS-1 and -5).
How people manage it
- Keep fluids up; the label warns that dehydration from vomiting or diarrhea can hurt the kidneys.
- Slow the titration or stay on the current dose step longer until GI effects settle.
Constipation
17%, 14% and 11% at 5, 10 and 15 mg vs 5% on placebo (SURMOUNT-1 and -2). Diabetes trials: 6%, 6% and 7% vs 1% (SURPASS-1 and -5).
How people manage it
- Drink more water and add soluble fiber.
Abdominal pain
9%, 9% and 10% at 5, 10 and 15 mg vs 5% on placebo (SURMOUNT-1 and -2 pooled)
How people manage it
- Slow the titration or stay on the current dose step longer until GI effects settle.
Indigestion and sulfur burps
Dyspepsia in 9%, 9% and 10% at 5, 10 and 15 mg vs 4% on placebo (SURMOUNT-1 and -2 pooled)
How people manage it
- Eat smaller, lighter meals, especially in the evening.
- Skip carbonated drinks if sulfur burps show up.
Fatigue
5%, 6% and 7% at 5, 10 and 15 mg vs 3% on placebo (SURMOUNT-1 and -2 pooled)
How people manage it
- Keep protein and fluids up while appetite is low.
Hair loss
5%, 4% and 5% at 5, 10 and 15 mg vs 1% on placebo. 7.1% of women vs 0.5% of men on drug; nobody stopped for it (SURMOUNT-1 and -2).
How people manage it
- Eat enough protein and stay hydrated; shedding is tied to fast weight loss.
Stopping treatment due to side effects
4.8%, 6.3% and 6.7% at 5, 10 and 15 mg vs 3.4% on placebo, mostly GI effects in the first months (SURMOUNT-1 and -2)
How people manage it
- Slow the titration or stay on the current dose step longer until GI effects settle.
Severe GI reactions
Listed in the label warnings
How people manage it
- Slow the titration or stay on the current dose step longer until GI effects settle.

How much is known

Strong human trials

Many phase 3 trials: SURPASS-1 to -5, SURPASS-PEDS, SURPASS-CVOT (13,299 patients; heart events HR 0.92 vs dulaglutide, noninferior), SURMOUNT-1 to -5, and two sleep apnea studies (AHI down 25.3 and 29.3 events per hour vs 5.3 and 5.5 on placebo). Microdosing, split dosing and research-grade vials have no trials. SURMOUNT-MAINTAIN is testing a step-down to 5 mg. The label's suicidal-ideation warning was removed in February 2026.