GLP-1 weight loss: what to know before you start

The conversation around weight management in Ireland has shifted dramatically in recent years, largely due to the arrival of GLP-1 receptor agonists. These medications have garnered significant attention, and as a pharmacist, I receive questions about them daily. Whether you have heard of them through news reports, social media, or conversations with friends, it is essential to understand what these treatments are, how they work, and the realities of using them within the Irish healthcare system.

GLP-1 receptor agonists work by mimicking a hormone naturally produced in the body called glucagon-like peptide-1. This hormone targets areas of the brain that regulate appetite and food intake. By mimicking this action, the medication helps you feel fuller sooner after eating and keeps you feeling satisfied for longer. This naturally leads to a reduction in calorie intake, which is the primary mechanism for weight loss. It is a physiological approach to managing weight, addressing the biological signals that drive hunger.

In Ireland, the landscape of these medications has evolved. Ozempic, a well-known brand name, contains the active ingredient semaglutide. It is crucial to note that Ozempic is licensed and prescribed exclusively for the treatment of type 2 diabetes. For patients with this condition, it may be covered under the medical card or the Long Term Illness scheme. However, it is not licensed as a weight-loss medication for those without diabetes.

For weight management specifically, Wegovy became available in Irish pharmacies in March 2025. Wegovy also contains semaglutide but is formulated and licensed specifically for weight loss. It is prescribed for adults with a Body Mass Index (BMI) of 30 or higher, or a BMI of 27 or higher if there is an accompanying weight-related comorbidity, such as high blood pressure or high cholesterol. Another option available is Mounjaro, which contains the active ingredient tirzepatide. Mounjaro works slightly differently by targeting two hormones, but it is prescribed under similar BMI criteria as Wegovy.

When considering these medications, it is vital to understand the financial implications. Unlike some treatments for chronic conditions, medications prescribed solely for weight loss, such as Wegovy and Mounjaro, are not currently covered by the medical card or the Drugs Payment Scheme (DPS). Patients must cover the full cost of these prescriptions privately. This is a significant factor to discuss with your healthcare provider when exploring your options.

While these medications can be highly effective, they are not a magic solution and must be part of a comprehensive approach to health. They are designed to be used alongside a reduced-calorie diet and increased physical activity. The medication helps manage the biological drive to eat, making it easier to adhere to lifestyle changes, but the lifestyle changes themselves remain the foundation of sustainable weight management. Relying solely on the medication without addressing diet and exercise will likely yield suboptimal results and make long-term maintenance difficult.

Like all medications, GLP-1 receptor agonists come with potential side effects. The most common issues reported by patients are gastrointestinal in nature. These can include nausea, vomiting, diarrhoea, constipation, and abdominal pain. These side effects are often most pronounced when starting the medication or when the dose is increased. Your doctor will typically start you on a low dose and gradually increase it to help your body adjust and minimise these effects. If you experience severe or persistent side effects, it is important to consult your doctor or pharmacist.

A critical safety concern in Ireland is the sourcing of these medications. The Health Products Regulatory Authority (HPRA) has issued strong warnings against purchasing weight-loss medications online from unregulated sources. There is a significant risk of receiving counterfeit, substandard, or entirely different substances, which can pose severe risks to your health. These are prescription-only medications that require medical supervision. They are not intended for cosmetic weight loss in individuals who are already at a healthy weight. Always obtain your medication through a registered Irish pharmacy with a valid prescription from a qualified healthcare professional.

If you are considering a GLP-1 medication for weight management, the first step is to have an open and honest conversation with your GP. They can assess your overall health, determine if you meet the criteria, and discuss whether this is the right path for you. At Blackrock Meds, we are always here to support you, answer your questions about your prescriptions, and provide guidance on managing any side effects.

Take care of yourselves, Aidan