Over Half of Weight Loss Injection Users Stop Treatment Within a Year

Over Half of Weight Loss Injection Users Stop Treatment Within a Year

What UK Patients Should Know

A recent large-scale Danish study, presented at the European Association for the Study of Diabetes (EASD), has found that more than half of individuals without diabetes discontinue the GLP-1 receptor agonist semaglutide within one year of starting treatment. This real-world data raises critical questions about long-term adherence, cost, and sustained weight loss. At Harley Street Obesity Clinic, we believe this study is important for anyone considering obesity treatments such as semaglutide (Ozempic) or its UK-licensed counterpart, Mounjaro, along with our comprehensive weight management programmes.

Key Findings from the Danish Study

  • The study tracked 77,310 adults (aged 18+) without diabetes, starting semaglutide for weight loss in Denmark between December 2022 and October 2023.
  • After 1 year:
    • Over 50% had discontinued treatment.
    • Discontinuation rates at 3, 6, and 9 months were approximately 18%, 31%, and 42% respectively.
  • Main reasons for stopping semaglutide included:
    • Cost: High out-of-pocket expense even in Denmark.
    • Side effects, especially gastrointestinal ones (nausea, vomiting, diarrhea).
    • Underlying medical or psychiatric conditions.
  • Demographics more likely to stop early:
    • Younger age (18-29) was associated with ~48% higher risk of stopping within a year vs middle age groups.
    • Men had higher discontinuation than women.
    • Those with prior gastrointestinal or psychiatric medication history.
    • People living in lower income areas.

Implications for Weight Loss Treatment in the UK

Issue

What It Means for UK Patients / Clinics

Semaglutide vs. Mounjaro

Semaglutide is well-known internationally and has been used for both diabetes and obesity. In the UK, Mounjaro (tirzepatide) is a GLP-1 (and GIP) agonist with some similar appetite-reducing effects. Patients and clinicians should note that outcomes / side effects / cost / adherence may differ between drugs.

Adherence & Long-Term Use

The Danish data emphasises that GLP-1 treatments are not “set-and-forget”. To maintain benefits (weight loss, risk reduction for obesity-related conditions), long-term adherence is often required. Stopping early is associated with weight regain and loss of the health benefits.

Cost & Access

Even in well-resourced health systems, out-of-pocket cost is a major barrier. In the UK, many obesity treatments are available via private clinics. NHS access is more limited. Patients need clarity on the total cost (drug, monitoring, support) before starting.

Side Effects & Patient Support

Gastrointestinal side effects are a common reason people stop. Clinics offering semaglutide or Mounjaro must have strong support structures: counselling, gradual dose escalation, dietary advice, side-effect management.

Patient Selection

Some patients may be more likely to persist: older, women, those without major comorbidities or psychiatric history. These factors can help personalise treatment plans.

At Harley Street Obesity Clinic: Our Approach to GLP-1 & Similar Therapies

At our clinic, we use evidence-based practices to maximise benefit and minimise drop-out. Key elements include:

  1. Thorough Assessment Before Treatment
    We review patients’ medical history (including gastrointestinal and psychiatric), current medications, lifestyle, and support systems. This helps predict who may struggle with side effects or cost barriers.
  2. Tailored Dosage & Support
    For those prescribed Mounjaro (since semaglutide for obesity may not always be available), we start low and increase carefully, monitor side effects, and coordinate with dietitians and behavioural coaches.
  3. Regular Monitoring & Follow-Up
    Frequent check-ins help us see how patients tolerate treatment, adjust support, and address problems early to reduce chances of discontinuation.
  4. Integrated Lifestyle & Psychological Support
    Medication is never a stand-alone fix. Nutrition, physical activity, mental health and behavioural counselling are essential to help sustain results and improve adherence.
  5. Cost Transparency
    We clearly explain the costs involved, what may or may not be covered by insurance/private arrangements, and what additional services or follow-ups entail.

What Patients Should Ask & Know Before Starting

  • Will I need this drug long term, or is it temporary?
  • What are the likely side effects and how do you manage them?
  • What are all the costs (drug + clinic fees + follow-ups)?
  • Are there patient support programmes (dietetic, psychological) included?
  • What are the expected results for someone with my age, BMI, comorbidities?

The Danish study highlights a sobering fact: even “breakthrough” weight-loss medications often fail in the real world not because they don’t work biologically, but because people struggle with cost, side effects, or practical barriers to staying on them.

For UK patients, Mounjaro and other GLP-1-based therapies offer powerful options, but their success depends on long-term commitment, good clinical support, and realistic expectations.

Here at Harley Street Obesity Clinic, our mission is to help patients navigate those challenges - offering the best medical tools, psychological support, and lifestyle change strategy to achieve sustainable weight loss and improved health.

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