Ozempic, Mounjaro and your mood: What the evidence actually shows
Most of the loud conversation around GLP-1 drugs, such as Ozempic and Mounjaro, centres on weight. But if you’re currently taking one or considering taking one, you may also be curious about what it means for how you feel. GLP-1 drugs have transformed obesity medicine, generated over £20 billion for manufacturer Novo Nordisk in 2024 alone, and quickly became one of the most discussed medical treatments in history. But at the heart of the GLP-1 hype lies another important question: how do GLP-1 drugs interact with mental wellbeing?
Dr Andy Zamar comments “Through weight loss, GLP-1 drugs can restore mobility and improve energy levels and confidence, which gives many patients a newfound sense of self. The value of these things in terms of mental wellbeing shouldn’t be underestimated.”
Indeed, for many patients, including those with type 2 diabetes, severe obesity, or cardiovascular risk, GLP-1 drugs have proved to be completely life-changing. The SELECT trial found that in the use of semaglutide, the active ingredient in Ozempic, there was 20% reduction in major adverse cardiac events in patients with pre-existing cardiovascular disease and obesity. It also produced meaningful weight loss across all groups of people.
But what happens when a drug that modulates the brain’s reward system meets someone with a history of depression? Here, we take a look at the potential interactions of GLP-1 drugs with mood, and underlying conditions such as depression, anxiety and eating disorders.
What GLP-1 drugs actually do to your body
In most users, GLP-1 (glucagon-like peptide-1) drugs cause a significant and sustained reduction in appetite. Many patients describe experiencing a silencing of ‘food noise’ and the constant preoccupation with eating that is characteristic of obesity and certain eating disorders.
But how do Ozempic and Mounjaro do this? The science behind this is surprisingly simple. GLP-1 is a hormone naturally released by the gut after eating. It:
- Prompts insulin secretion
- Slows gastric emptying and regulated digestion
- Communicates to your brain that you are full
Drugs like Ozempic mimic this signal, which keeps it active for longer and more potently than the natural hormone.
Do GLP-1 drugs affect your brain?
What the dominant public conversation has been slow to engage with is where else GLP-1 receptors are found in the brain.
The answer is significant: GLP-1 receptors are densely expressed in the core of the brain’s dopamine reward system.
This means GLP-1 drugs do not simply regulate appetite, but also the circuits governing:
- Motivation
- Craving
- The experience of pleasure.
So, these drugs are “acting on the system that makes you want the cake, not just the system that makes you feel full”.
It’s clear that GLP-1 drugs directly impact the brain’s reward system – which in someone with depression or anxiety, for example, is worth taking a closer look at. The American Psychological Association issued a warning in July 2025 that warrants consideration. Whilst GLP-1 drugs have shown promise in blunting addictive behaviours, they may be depleting dopamine responses to more than just food – the effects of which can feel more pronounced for those with pre-existing conditions. For example, dopamine responses produced by engaging in hobbies, time with loved ones, and the little pleasures that ordinarily sustain daily wellbeing.
The psychosocial implications of accelerating GLP-1 use also remain unclear. A study by a Harvard economics professor suggests that women taking GLP-1 drugs may boost their chances of landing a job and a life partner. This leaves us facing more than a chicken-and-egg question: a self-reinforcing cycle in which the drug does not just treat the condition, but reshapes the conditions under which people are valued.
Will a GLP-1 drug affect my mood?
For most patients, they appear psychiatrically safe. For particular subsets of people – such as those with pre-existing psychiatric history, low dopamine function, or genetic predisposition to certain mental health conditions – the risk profile may be different.
What does research actually show us about GLP-1 drugs and their interplay with mental health?
On one side, a study in Scientific Reports found significantly increased risks amongst GLP-1 users, including:
- 98% increased risk of any psychiatric disorder
- 195% higher risk of major depression
- 108% increased risk of anxiety
- 106% elevated risk of suicidal behaviour.
Females and patients aged 18-49 showed the highest vulnerability, somewhat unsurprisingly given the particular societal pressures faced by members of these groups.
On the other hand: one study found that the active ingredient in Ozempic was associated with significantly lower risk of suicidal ideation compared to other anti-obesity medications.
The largest psychiatric safety study on GLP-1 drugs to date, involving over 107,000 patients, found that GLP-1 medications were not associated with increased risk of serious psychiatric adverse events overall. Later studies of major semaglutide trials found no differences in depression, suicidal ideation, or suicidal behaviour compared to placebo. However, it’s worth noting that both these studies excluded patients with known psychiatric conditions.
What does this tell us? At this point in our understanding, simply that the true clinical position remains uncertain.
I have a history of disordered eating. Is a GLP-1 drug safe for me?
This is a really important question to ask, and the honest answer is that GLP-1 drugs aren’t currently recommended for people with a history of eating disorders. Because these medications strongly suppress appetite, they can reinforce restrictive patterns or intensify binge-restrict cycles.
Interestingly, one report found that 32% of people with a diagnosed eating disorder had already used a GLP-1 drug, with 22% currently using one at the time of the survey. And at the same time, psychiatric screening before prescribing is not a standard practice.
A systematic review of adults seeking obesity treatment found that:
- 14% had binge eating disorder on clinical interview
- Up to 26% reported moderate-to-severe binge eating on self-report
The risk is specific and well-documented. For example, in patients with a history of restrictive eating, the dramatic suppression of appetite that GLP-1 drugs produce can reinforce food restriction behaviours to a pathological degree.
For people trapped within binge-restrict cycles, the drug’s suppressive effect during restriction phases may intensify any subsequent compensatory binge. A study using WHO data found disproportionate reporting of eating disorder adverse events for all three major GLP-1 drugs.
GLP-1 drugs are not recommended for patients with a history of anorexia nervosa or bulimia. The National Eating Disorders Association states clearly that it is not yet known whether these drugs are safe for people with eating disorders.
It’s important that the prescribing conversation across all clinical settings catches up to this. Dr Andy Zamar comments, “whilst GLP1s can produce amazing effects and drastically improve quality of life, we must consider whether continued use is wise in risky cases.” If any of this resonated, it’s best to speak with your psychiatrist first before starting a course of Ozempic or Mounjaro.
Can I take a GLP-1 drug if I have depression?
The short answer is yes. Having depression doesn’t automatically rule out a GLP-1 drug. Whilst some observational studies have reported higher rates of low mood amongst users, this kind of research can’t show that the drug is the cause. In addition, the FDA concluded that it had not identified an increased risk of suicidal ideation or behaviour through GLP-1 use, and removed all relevant warnings from these medications in 2026.
Ultimately, what matters most is that your prescriber is aware of your full history so that they can monitor your mood and continue to coordinate your care safely and effectively. If you’re concerned about the impacts of weight loss drugs on your mental health and want extra support, speak to one of our doctors at The London Psychiatry Centre.
What to watch for – and when to seek help
Signs that a GLP-1 drug may be affecting your mental health
If you’re on a GLP-1 drug, have a history of any psychiatric condition, or are simply noticing changes in your mood or relationship with food – the key warning signs below may be of interest to you:
- A flattening of mood or pleasure that goes beyond appetite. Food has become less compelling, but so have other things that once brought enjoyment.
- Increasing restriction of food intake beyond the drug’s intended effect: eating less than is recommended, skipping meals, or feeling satisfied by quantities that concern those around you.
- Worsening anxiety, intrusive thoughts about food or body weight, or a preoccupation with eating that has intensified rather than lessened.
- Low mood, emotional withdrawal, loss of motivation, or a sense of flatness that was not present before starting the medication.
- Thoughts of self-harm or suicide – if these are present, contact a clinician immediately.
For the first time, we have medications that produce meaningful, sustained weight loss without surgery. But the mind and body are not separate systems.
You don’t need to wait for something to go wrong to ask the question. At The London Psychiatry Centre, our clinicians offer comprehensive assessment and treatment for depression, anxiety, OCD and eating disorders, which includes access to our rTMS clinic.
If you are currently taking or thinking about taking a GLP-1 drug and have a history of any of these conditions, a psychiatric assessment at The London Psychiatry Centre is worth considering.
Contact us on 020 7580 4224 or info@psychiatrycentre.co.uk to book a consultation.