Do GLP-1 drugs cause depression? After reports of suicidal thoughts and self-harm in people using some of these medicines, the European Medicines Agency (EMA), the UK's Medicines and Healthcare products Regulatory Agency (MHRA) and the US Food and Drug Administration (FDA) each reviewed the evidence, and none concluded that the medicines cause these problems.
The EMA (April 2024) found the evidence does not support a causal link between the GLP-1 medicines it reviewed and suicidal and self-injurious thoughts and actions; the MHRA (September 2024) said the available evidence does not establish one, including for depression. UK SmPCs checked for this guide do not list depression or suicidal thoughts as a warning or side effect.
This is information only, not medical advice; a prescriber decides whether a medicine suits you. If you need urgent help or feel unsafe, go straight to getting help urgently.
Do GLP-1 drugs cause depression? Why regulators looked
In July 2023 the EMA's safety committee, the PRAC, began reviewing the risk of suicidal thoughts and thoughts of self-harm with GLP-1 receptor agonists, in a review triggered by the Icelandic medicines agency following reports in people using liraglutide and semaglutide. The EMA said it was not yet clear whether the reported cases were linked to the medicines themselves or to people's underlying conditions or other factors.
What the European review concluded
After asking the companies for more data in November 2023, the PRAC concluded in April 2024 that "the available evidence does not support a causal association" between the GLP-1 receptor agonists dulaglutide, exenatide, liraglutide, lixisenatide and semaglutide "and suicidal and self-injurious thoughts and actions". Having reviewed non-clinical studies, clinical trials, post-marketing surveillance data and other studies, it considered that no update to the product information was warranted.
The conclusion does not mention depression, nor does it name tirzepatide (Mounjaro). Foundayo (orforglipron) was first authorised in the UK in August 2026, after the review.
What the MHRA concluded for the UK
The MHRA says that after a potential risk of suicidal thoughts and self-harm was identified in July 2023, the companies' safety reviews of the same five medicines also looked at the risk of depression. On 4 September 2024 it announced that "the available evidence does not establish a causal relationship" between GLP-1 receptor agonists and "suicidal behaviour, suicidal ideation, self-injury and depression". Its evaluation of UK post-marketing data aligned with the European review's conclusions, and it found no update to the product information warranted at that time. It said it would "continue to closely monitor the risk of severe psychiatric reactions".
Its GLP-1 medicines page, which counts tirzepatide as a GLP-1 medicine, gives a similar general conclusion; the 2024 announcement did not name tirzepatide.
The FDA's evaluation in the US
In January 2024 the FDA, in an update that listed tirzepatide among the GLP-1 medicines, said its preliminary evaluation "has not found evidence that use of these medicines causes suicidal thoughts or actions", but that because few such events were seen it could not "definitively rule out that a small risk may exist". In January 2026, after a comprehensive review found no increased risk of suicidal ideation or behaviour, it asked the makers of Saxenda, Wegovy and Zepbound to remove information about that risk from their US labelling. Its meta-analysis of 91 placebo-controlled trials (107,910 patients) did not show an increased risk of these events, or of other relevant psychiatric adverse events such as anxiety, depression, irritability or psychosis.
What the UK product information says about mood
Section 4.4 of a medicine's Summary of Product Characteristics (SmPC) sets out special warnings and precautions. The UK SmPCs for the Wegovy injection, Wegovy tablets, Mounjaro KwikPen and Foundayo (versions revised between June and September 2026) do not mention depression, low mood, psychiatric reactions or suicidal thoughts in section 4.4 or in the section 4.8 side-effect tables, and their patient leaflets do not list them as side effects.
Foundayo's leaflet lists St John's wort, "a herbal product used for depression and anxiety", among medicines that may reduce the amount of Foundayo in your blood; its SmPC says to avoid strong CYP3A4 inducers such as St John's wort when taking orforglipron. More on each medicine: Mounjaro, Wegovy, Wegovy pill and Foundayo.
If your mood drops during treatment
The NHS says a low mood often gets better after a few days or weeks, but one that lasts 2 weeks or more could be a sign of depression. Its non-urgent advice is to see a GP if you've had a low mood for more than 2 weeks, you're struggling to cope with it, things you're trying yourself are not helping, or you would prefer a referral from a GP. In England, if you're 18 or over (or 16 or over in some areas), you can refer yourself to an NHS talking therapies service without talking to a GP.
The FDA advises telling a healthcare professional about new or worsening depression, suicidal thoughts or any unusual changes in mood or behaviour. Whether to continue, pause or stop a GLP-1 medicine is for your prescriber to decide with you.
If you're feeling like you want to end your life, the NHS says it's important to tell someone. Options it lists include an emergency GP appointment, NHS 111 (online, or on 111 choosing the mental health option), your mental health crisis team if you have one, and Samaritans, free on 116 123, 24 hours a day, every day. The NHS says to go to A&E or get an ambulance on 999 now if someone's life is at risk (for example, they have seriously injured themselves or taken an overdose), if you have seriously harmed yourself or feel you may be about to harm yourself, or if you do not feel you can keep yourself or someone else safe. Someone else can get the ambulance or take you to A&E. Do not drive yourself to A&E, and bring any medicines you take with you. You will not be wasting anyone's time.
Reporting a suspected side effect
If you think a GLP-1 medicine has affected your mood, tell your prescriber and consider a report to the MHRA's Yellow Card scheme: anyone can report an issue with a medicine, and the MHRA says reports help it identify new safety issues as early as possible. Other effects are covered in managing GLP-1 side effects.
Frequently asked questions
Is depression a listed side effect of Mounjaro, Wegovy or Foundayo?
Not in the UK SmPCs checked for this guide (Wegovy injection and tablets, Mounjaro KwikPen and Foundayo): none mentions depression, low mood or suicidal thoughts in its warnings or side-effect tables. Tell your prescriber or GP about any change in your mood.
Did the safety reviews include tirzepatide?
The EMA's and MHRA's 2024 conclusions named dulaglutide, exenatide, liraglutide, lixisenatide and semaglutide, not tirzepatide, although the MHRA's GLP-1 medicines page, which counts tirzepatide among them, gives a similar general conclusion. The FDA's January 2024 evaluation listed tirzepatide, and its January 2026 request covered Zepbound (tirzepatide).
Should I stop my GLP-1 medicine if I feel low?
Speak to your prescriber or GP; whether to continue, pause or stop is for your prescriber to decide with you. If you do not feel you can keep yourself or someone else safe, do not wait for an appointment: go to A&E or get an ambulance on 999 now.
What should I do if I have thoughts of harming myself?
Tell someone and get help straight away. The NHS says to go to A&E or get an ambulance on 999 now if someone's life is at risk, you have seriously harmed yourself, you feel you may be about to harm yourself, or you do not feel you can keep yourself or someone else safe. Other options include NHS 111, an emergency GP appointment, your mental health crisis team if you have one, and Samaritans, free on 116 123 at any time.
Sources
- EMA: statement on the review (11 July 2023); PRAC highlights, 8-11 April 2024.
- MHRA: news story (4 September 2024); GLP-1 medicines: what you need to know; Yellow Card.
- FDA: January 2024 update; January 2026 Drug Safety Communication.
- emc SmPCs and leaflets: Wegovy injection (SmPC, leaflet); Wegovy tablets (SmPC, leaflet); Mounjaro KwikPen (SmPC, leaflet); Foundayo (SmPC, leaflet).
- NHS: low mood, sadness and depression; help for suicidal thoughts; urgent help for mental health; find NHS talking therapies.