Saxenda (liraglutide 3.0 mg) is a GLP-1 receptor agonist licensed in the UK for weight management in adults with obesity or overweight with comorbidities. Whilst there is no established causal link between Saxenda and mental health conditions, some patients have reported mood changes during treatment. The MHRA and EMA continue to monitor psychiatric adverse effects through post-marketing surveillance. This article examines the relationship between Saxenda and mental health, identifies patients who may require additional caution, and provides guidance on monitoring mental wellbeing throughout treatment. Understanding these considerations helps ensure safe, effective weight management that prioritises both physical and psychological health.

What Is Saxenda and How Does It Work?

Saxenda (liraglutide 3.0 mg) is a prescription-only injectable medicine licensed in the UK for weight management in adults with obesity (BMI ≥30 kg/m²) or overweight (BMI ≥27 kg/m²) with at least one weight-related comorbidity, such as type 2 diabetes or hypertension. It is administered once daily via subcutaneous injection and is intended to be used alongside a reduced-calorie diet and increased physical activity.

Saxenda belongs to a class of medicines called glucagon-like peptide-1 (GLP-1) receptor agonists. It works by mimicking the action of GLP-1, a naturally occurring hormone released by the intestine after eating. The mechanism of action involves several pathways: it slows gastric emptying, which prolongs the feeling of fullness after meals; it acts on appetite centres in the hypothalamus to reduce hunger and food cravings; and it helps regulate blood glucose levels by enhancing insulin secretion when blood sugar is elevated.

Clinical trials have demonstrated that Saxenda, when combined with lifestyle modifications, can lead to clinically significant weight loss. The treatment involves a weekly dose titration schedule, starting at a lower dose and gradually increasing to the full 3.0 mg dose to improve tolerability. According to NICE Technology Appraisal guidance, liraglutide 3.0 mg is recommended as an option for managing overweight and obesity in specific patient groups, typically within specialist weight management services. NHS availability is restricted to patients meeting strict eligibility criteria, with treatment reviewed after 12 weeks at the full dose and continued only if at least 5% of initial body weight has been lost.

Common side effects include gastrointestinal symptoms such as nausea, vomiting, diarrhoea, and constipation, which typically improve over time. Patients should report any suspected side effects to their healthcare professional or directly to the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk). While there is no established causal link between Saxenda and mental health conditions, regulatory bodies continue to monitor reports of mood changes during treatment.

Depression, Anxiety and Mood Changes During Saxenda Treatment

The relationship between Saxenda and mental health remains an area of ongoing clinical scrutiny. There is no established causal link between liraglutide and the development of depression or anxiety disorders, as confirmed by recent reviews by the MHRA and European Medicines Agency (EMA) Pharmacovigilance Risk Assessment Committee (PRAC). However, these regulatory bodies continue to monitor post-marketing surveillance data for potential psychiatric adverse effects.

Some patients have reported experiencing mood changes, low mood, anxiety, or depressive symptoms whilst taking Saxenda. These reports have prompted healthcare professionals to remain vigilant, particularly given that weight management itself can be emotionally challenging. It is important to recognise that individuals seeking weight loss treatment may already have underlying mental health vulnerabilities, and the process of significant lifestyle change can be psychologically demanding.

The Summary of Product Characteristics (SmPC) for Saxenda notes that mood disorders including depression have been reported in clinical practice, though with uncommon frequency. Factors that may potentially contribute to mood changes during treatment include:

• The psychological impact of dietary restriction and lifestyle changes

• Pre-existing mental health conditions that may fluctuate

• Gastrointestinal side effects affecting quality of life and wellbeing

• The emotional aspects of weight management

• Individual psychological responses to body changes

Patients should be advised to monitor their mental wellbeing throughout treatment and report any concerning symptoms promptly. Healthcare professionals should conduct a thorough mental health assessment before initiating Saxenda and maintain regular follow-up. If significant mood disturbance, persistent low mood, anxiety, or suicidal ideation develops, patients should seek urgent medical advice. Treatment discontinuation should be considered while appropriate mental health support is arranged, in line with clinical judgement.

Who Should Avoid Saxenda Due to Mental Health Concerns?

Whilst Saxenda is not absolutely contraindicated in individuals with mental health conditions, careful risk-benefit assessment is essential before prescribing to patients with current or previous psychiatric disorders. Healthcare professionals should exercise particular caution and consider alternative weight management strategies in certain circumstances.

Patients with active severe depression or those experiencing suicidal ideation would generally benefit from mental health stabilisation under appropriate psychiatric care before commencing Saxenda. The additional psychological demands of weight loss treatment may be challenging during periods of mental health vulnerability. Similarly, individuals with poorly controlled anxiety disorders or those in acute mental health crisis may require stabilisation before considering pharmacological weight management.

Those with a history of eating disorders, including anorexia nervosa, bulimia nervosa, or binge eating disorder, require specialist assessment in line with NICE guidance (NG69). The focus on weight loss and appetite suppression may potentially affect disordered eating patterns. A multidisciplinary approach involving mental health specialists, dietitians, and eating disorder services is advisable before considering Saxenda in this population.

Additional considerations include:

• Patients taking psychotropic medications – while direct drug interactions are limited, Saxenda's effect on delaying gastric emptying may affect absorption of some oral medicines

• Individuals with bipolar disorder, particularly during unstable phases

• Those with substance use disorders, as weight loss medications require careful adherence

• Patients lacking adequate mental health support networks

Before prescribing Saxenda, clinicians should:

• Conduct a comprehensive mental health history

• Screen for current mood disorders using validated tools

• Assess suicide risk and self-harm history

• Ensure appropriate mental health support is in place

• Discuss potential risks openly with the patient

• Arrange more frequent follow-up for vulnerable individuals

Patients should be empowered to make informed decisions, understanding that alternative weight management approaches, including psychological interventions, dietary support, and increased physical activity, may be more appropriate for their circumstances.

Managing Mental Wellbeing While Taking Saxenda

For patients deemed suitable for Saxenda treatment, proactive mental health monitoring is essential throughout the treatment course. A collaborative approach between the prescribing clinician, the patient, and where appropriate, mental health services, optimises both physical and psychological outcomes.

Before starting treatment, patients should be educated about potential mood-related side effects and encouraged to maintain open communication with their healthcare team. Establishing a baseline mental health assessment using standardised screening tools such as the PHQ-9 (Patient Health Questionnaire-9) for depression or GAD-7 (Generalised Anxiety Disorder-7) for anxiety provides a reference point for monitoring changes.

During treatment, patients should:

• Monitor mood regularly and keep a symptom diary if helpful

• Maintain regular contact with their GP or prescribing clinician, typically monthly initially

• Report any concerning symptoms immediately, including persistent low mood, anxiety, irritability, or thoughts of self-harm

• Continue existing mental health treatments and medications as prescribed

• Engage with psychological support such as counselling or cognitive behavioural therapy (CBT) if needed

• Prioritise self-care, including adequate sleep, stress management, and social connection

• Ensure nutritional adequacy through balanced eating despite reduced appetite

• Maintain physical activity, which has proven mental health benefits

Healthcare professionals should schedule regular review appointments to assess both weight loss progress and mental wellbeing. Treatment should be discontinued if a 5% weight loss has not been achieved after 12 weeks at the full 3.0 mg daily dose, in line with the SmPC and NICE guidance. If mood deterioration occurs, a thorough evaluation is required to determine whether symptoms are related to Saxenda, the weight loss process itself, or independent factors. Management options include:

• Dose adjustment or temporary treatment pause

• Enhanced psychological support or referral to mental health services

• Optimisation of existing mental health treatments

• Discontinuation of Saxenda if symptoms are severe or persistent

When to seek urgent help: Patients should call 999 if they are at immediate risk of harm to themselves or others. For urgent but non-life-threatening mental health concerns, they should contact NHS 111, their local NHS urgent mental health helpline, or their GP. The Samaritans (116 123) offer confidential emotional support.

Patients should report any suspected side effects to their healthcare professional or directly to the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk). Successful weight management with Saxenda requires a holistic approach that prioritises mental health alongside physical health outcomes, ensuring patient safety and wellbeing remain paramount throughout treatment.

Frequently Asked Questions