Introduction
GLP-1 medicines such as Wegovy (semaglutide) and Mounjaro (tirzepatide) are effective treatments for weight loss and improving blood sugar control. If you have a history of cancer and are now in remission, you may be wondering whether these medicines are safe for you.
Research so far has not shown a proven link between GLP-1 medicines and cancer in humans, but long-term studies are ongoing. For patients in remission, these medicines may be suitable if used with caution and regular follow-up from your GP or specialist.
GLP-1 Medicines and Cancer: What We Know
In animal studies, GLP-1 medicines caused thyroid C-cell tumours (medullary thyroid carcinoma) in rodents (1,2).
In human studies, no clear increase in cancer risk has been found to date, but data are still being collected (3,4).
Because of the animal findings, GLP-1 medicines are not suitable for patients with a personal or family history of: Medullary Thyroid Carcinoma (MTC) and Multiple Endocrine Neoplasia type 2 (MEN2) (2)
Patients in Cancer Remission
If you are in remission, GLP-1 medicines may be an option, but you must:
- Continue with regular monitoring through your GP or cancer specialist.
- Be aware that some side-effects of GLP-1 therapy (such as fatigue, nausea, or weight loss) can overlap with cancer-related symptoms.
- Report any new or unexplained symptoms promptly.
Red Flag Symptoms to Watch For
Contact your GP or specialist if you experience:
- Breathlessness
- Difficulty swallowing
- Skin changes such as new lumps, moles, or scaly patches that don’t heal
- Growing lumps anywhere in the bod
- Persistent fatigue or weakness
Summary
GLP-1 medicines like Wegovy and Mounjaro have not been shown to cause cancer in humans, but careful monitoring is important for anyone with a cancer history.
If you are in remission, these treatments may be suitable, provided you stay under the care of your GP or specialist.
Always watch for red flag symptoms and seek urgent help if symptoms are severe.
Avoid GLP-1 medicines completely if you or a family member has a history of MTC or MEN2.
With proper follow-up and communication, GLP-1 medicines can be used safely as part of a long-term health and weight management plan in many people with a cancer history.
References
- Nauck MA, Friedrich N. Do GLP-1–based therapies increase cancer risk? Diabetes Care. 2013;36 Suppl 2:S245-52.
- U.S. Food and Drug Administration (FDA). Wegovy prescribing information. 2023.
- Boniol M, Franchi M, Bota M, Bonovas S, Russo AG. GLP-1 receptor agonists and cancer risk: A systematic review and meta-analysis of randomised controlled trials. Diabetes Obes Metab. 2022;24(1):36–46.
- Kristensen SL, Rørth R, Jhund PS, Docherty KF, Sattar N, Preiss D, et al. Cardiovascular, mortality, and kidney outcomes with GLP-1 receptor agonists in patients with type 2 diabetes: A systematic review and meta-analysis. Lancet Diabetes Endocrinol. 2019;7(10):776–85.