Does Mounjaro cause hair loss?

Mounjaro (tirzepatide) is approved for type 2 diabetes and often prescribed off‑label for weight loss. Common side effects include nausea, vomiting, diarrhea, and abdominal discomfort. Although hair loss is not listed in the official prescribing information, clinical trials of Zepbound (same active ingredient) reported hair loss in 4–5 percent of participants versus 1 percent on placebo.

Possible mechanisms

Experts suspect hair thinning may result from rapid weight loss rather than a direct drug effect. Significant, sudden weight reduction can trigger telogen effluvium, a stress‑induced shift of hair follicles into their resting phase, leading to increased shedding. Typically, this resolves within 3–6 months as follicles re‑enter the growth phase.

Reduced caloric intake may also cause nutritional deficiencies (iron, zinc, biotin, vitamin D) that impact hair health.

Other side effects of Mounjaro

  • Nausea
  • Diarrhea
  • Decreased appetite
  • Vomiting
  • Constipation
  • Indigestion
  • Stomach pain
  • Weight loss
  • Injection site reactions
  • Fast heartbeat
  • Bloating and burping
  • Heartburn (GERD)
  • Hair loss (reported)

Serious side effects

  • Anaphylaxis (hives, throat swelling, breathing difficulty)
  • Increased risk of thyroid tumors (watch for neck lumps, hoarseness)
  • Pancreatitis (severe abdominal pain, back pain)
  • Kidney damage or failure (dehydration, low urine output)
  • Gallbladder issues (upper abdominal pain, fever, nausea)
  • Hypoglycemia when combined with insulin or sulfonylureas
  • Diabetic retinopathy progression (vision changes)
  • Worsening depression or suicidal thoughts

Ozempic and Wegovy

Both contain semaglutide. In Wegovy trials, 3–4 percent of adults and adolescents reported hair loss versus 0–1 percent on placebo. Ozempic’s prescribing info does not list hair loss, though some users report it.

Preventing hair loss on Mounjaro

  • Maintain a balanced diet rich in protein, iron, zinc, biotin, and vitamin D
  • Consider supplements if dietary intake is insufficient
  • Use topical treatments like minoxidil for at least 6 months if needed
  • Manage stress through exercise, meditation, or therapy
  • Avoid tight hairstyles, heat styling, and harsh chemical treatments

Will hair regrow?

In most cases, telogen effluvium from rapid weight loss is temporary. Hair typically regrows within a few months once the body adapts. Permanent loss is uncommon but may involve other factors (genetics, age, underlying conditions). Discuss persistent hair thinning with your healthcare provider.

Sources

  • Mounjaro (tirzepatide) injection, Eli Lilly & Company. Last updated 11/2024.
  • Wegovy (semaglutide) prescribing information, Novo Nordisk. Last updated 11/2024.
  • Ozempic (semaglutide) prescribing information, Novo Nordisk. Last updated 11/2024.