Can Mounjaro cause depression?

Simon Edward • 5 December 2025

You might have heard that Mounjaro is linked with depression and anxiety. Let's look at the facts behind the claims.



You might have heard that Mounjaro is linked with depression and anxiety. Let's look at the facts behind the claims.

Today, many people living with obesity are turning to injectable medications like Wegovy (semaglutide) and Mounjaro (tirzepatide) to kickstart their weight loss journeys.


This new generation of weight loss drugs is helping transform lives. When taking the drug alongside a healthy diet and regular exercise, Wegovy users can expect to lose around 15% of their body weight.¹ With Mounjaro, meanwhile, the average weight loss is around 21%.²


However, as with all medications, there's the possibility of side effects. The most common are gastrointestinal issues like nausea, vomiting and constipation. But it's reasonable to wonder, 'Could Mounjaro impact my mental health, too?' 


Establishing the facts: the situation with Wegovy

In a previous article, we discussed whether Wegovy is linked to depression.


After reviewing the available data, the European Medicines Agency (EMA) concluded that no causal link has been found between GLP-1 medications and suicidal thoughts or self-harm.³


This stance hasn't changed. The MHRA still licenses both Wegovy and Mounjaro in the UK, and both drugs are considered safe when prescribed by a medical professional.


So, what about Mounjaro and mental health?

So far, anecdotal evidence suggests there is little risk of Mounjaro impacting mental health. This is despite in-depth clinical trials and ongoing risk assessments by medical bodies.


Let's look at two examples of how medical bodies continuously monitor the safety of drugs available in the UK and Europe.


The EudraVigilance database

EudraVigilance is a centralised EU database maintained by the European Medical Agency (EMA).


Experts examined the anonymous reports within the database for a 2024 report. They found that psychiatric events account for only 1.2% of the total reports associated with semaglutide, liraglutide, and tirzepatide.⁴

Picture of a medical scientist examining a report on a computer.

The MHRA's Yellow Card scheme

Medical guidance issued by the UK government considers feedback submitted via the Yellow Card scheme, which helps safeguard users of medical products in the UK.

The most common side effects reported by actual users of Mounjaro are gastrointestinal, and mostly mild and temporary as the patient adjusts to the dosage. Depression, suicidal thoughts or mood disorders are not called out as significant Yellow Card submissions.⁵

What NICE says

The National Institute for Health and Care Excellence (NICE) also provides guidance and support for the NHS and other UK medical bodies.


NICE's appraisal of tirzepatide does not list depression or mood disorders under common, rare, or significant side effects. Since the guidelines were published, there has been no requirement for investigation.⁶

The key facts

  • In recent years, the relationship between GLP-1 medications and depression has been assessed, with no significant relationship identified.
  • While product information can mention depressive or suicidal thoughts as a precaution, neither clinical trials nor market reports suggest a definite link.
  • Appropriate medical bodies report no concerns between the injections and mental health. However, they do recommend that users should seek advice from a healthcare professional if they're experiencing depression, anxiety or suicidal thoughts. 

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Sources

1. Wilding, J.P.H. et al. (2021) "Once-weekly semaglutide in adults with overweight or obesity" The New England Journal of Medicine, 384(11) https://doi.org/10.1056/NEJMoa2032183


2. Jastreboff, A.M. et al. (2022) "Tirzepatide Once Weekly for the Treatment of Obesity" The New England Journal of Medicine, 387(3) https://doi.org/10.1056/NEJMoa2206038


3. European Medicines Agency (2024) Meeting highlights from the Pharmacovigilance Risk Assessment Committee (PRAC) 8-11 April 2024. Retrieved from https://www.ema.europa.eu/en/news/meeting-highlights-pharmacovigilance-risk-assessment-committee-prac-8-11-april-2024


4. Tobaiqy, M. & Elkout, H. (2024) "Psychiatric adverse events associated with semaglutide, liraglutide and tirzepatide: a pharmacovigilance analysis of individual case safety reports submitted to the EudraVigilance database" International Journal of Clinical Pharmacy, 46(2) https://doi.org/10.1007/s11096-023-01694-7


5. Medicines & Healthcare products Regulatory Agency (2025) Guidance: GLP-1 medicines for weight loss and diabetes: what you need to know. Retrieved from https://www.gov.uk/government/publications/glp-1-medicines-for-weight-loss-and-diabetes-what-you-need-to-know/glp-1-medicines-for-weight-loss-and-diabetes-what-you-need-to-know


6. National Institute for Health and Care Excellence (n.d.) Tirzepatide. Retrieved from https://bnf.nice.org.uk/drugs/tirzepatide/

This article was reviewed and approved by Lujain Alhassan, Bariatric Dietitian, and Sarah Abdula, Specialist Dietitian, on 27 November 2025.


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