Who Can Prescribe Weight Loss Medications?

Wednesday, April 9, 2025

If you're exploring options to support your weight management, you may have come across prescription treatments like Mounjaro or Orlistat. But who can actually prescribe these medicines, and how do you know if they’re suitable for you?

In this guide, we’ll explain the types of healthcare professionals who can prescribe weight loss treatments, how eligibility is assessed, and how the NHS and private services differ.

Are weight loss medications prescription-only?

Medicines like Mounjaro and Wegovy are only available on a prescription. This means they can’t be bought over the counter and must be prescribed by a qualified healthcare professional following a consultation.

These treatments are usually considered for people living with obesity (typically a BMI of 30 or above), or for those with a slightly lower BMI who also have weight-related health conditions like type 2 diabetes or high blood pressure. (1)

Higher-strength Orlistat (120mg) is also prescription-only. There is a lower strength (60mg) which is available over the counter, but only from pharmacies.

Who can prescribe them?

In the UK, weight loss medications can be prescribed in person or online by:

GPs and doctors in NHS or private settings
Independent prescribers (such as qualified pharmacists and nurse practitioners)
Specialist weight management clinics

At Oxford Online Pharmacy, our consultation service is reviewed by independent UK doctors who assess whether a treatment is appropriate for you. If a prescription is issued, it is dispensed by our Oxfordshire pharmacy team.

What treatments are available?

There are several licensed medicines available in the UK, each with different mechanisms:

Orlistat (also known as Xenical or Alli) – works by reducing fat absorption
Liraglutide (Saxenda) – a daily injection that mimics the body’s satiety (fullness) hormone (GLP-1)
Semaglutide (Wegovy) – a once-weekly GLP-1 injection
Tirzepatide (Mounjaro) – a newer treatment that acts on both GLP-1 and GIP receptors

Not all treatments are suitable for everyone. The most appropriate option depends on your medical history, BMI, other medications, and lifestyle factors.

NHS vs private prescribing

The NHS follows strict guidance from NICE (the National Institute for Health and Care Excellence). This includes eligibility criteria around BMI thresholds, co-existing health conditions, and structured support plans. (2)

Some newer medicines like Mounjaro are being rolled out gradually across NHS services. If you're eligible, your GP or weight management team may be able to refer you.

However, availability may vary by region.

Private services, like Oxford Online Pharmacy, provide access to weight management treatments through online consultations. These are reviewed by independent UK prescribers, and any approved treatment is issued safely through our registered pharmacy.

What about safety and side effects?

All prescription medicines carry a risk of side effects, and weight loss treatments are no exception. The most common side effects for GLP-1 medicines like Wegovy or Mounjaro include:

Nausea
Constipation
Diarrhoea
Indigestion

These may affect more than 1 in every 10 people who use the medicine. More serious but rarer side effects include pancreatitis or gallbladder problems. Your prescriber will discuss these with you, and a full list is included in the patient information leaflet. (3)

Considering treatment?

If you're thinking about treatment, it's important to engage with a safe, regulated service. At Oxford Online Pharmacy, our pharmacist-led team works with independent doctors to assess whether a treatment is right for you.

Start with an online consultation to explore your options. You’ll get clear, honest advice and access to UK-licensed treatments if appropriate for your health needs.