What you need to know before considering weight loss jabs

Kate Ng
·Trending Lifestyle Reporter
Updated ·5-min read
Ozempic Insulin injection pen for diabetics and weight loss.
Weight loss medications have risen in popularity - but should you actually be taking them? (Getty Images)

Over the last year, weight loss jabs have become highly popular, particularly as the NHS began offering Wegovy in late 2023 and will start offering Mounjaro to patients in March 2025.

There has also been a surge in demand for weight loss jabs after a number of celebrities began using Ozempic, which is primarily used to treat type 2 diabetes, to lose significant amounts of weight.

In the UK, the first patients to receive Wegovy from the NHS, a medication containing semaglutide that is approved for weight loss, began taking the jabs last year.

However, the rollout has been slow, with a very small proportion of the 3.4 million patients in England who are eligible for the drug actually getting access to it. According to the BBC, the health service isn’t able to give the medication to everyone who is eligible immediately or it would "simply bankrupt the NHS".

Some people may turn to private healthcare providers in order to get their hands on the weight loss jabs. However, Britons have been repeatedly warned about the dangers of using these medications without a doctor’s supervision following serious complications experienced by some patients.

If you are considering taking weight loss jabs this year, here’s everything you need to know about eligibility, safety, and whether you should really be on them.

Waist measurement in medical practice. The nurse is using a tape measure
Patients must be assessed by their healthcare provider in order to determine if they meet the eligibility criteria for weight loss jabs. (Getty Images)

Wegovy is the brand name for semaglutide which is licensed and approved for managing obesity and overweight. It differs from Ozempic, which is another brand name for semaglutide and is used for treating type 2 diabetes. Ozempic should not be prescribed solely for weight loss.

The NHS began offering Wegovy in September 2023 as an option for weight management in line with guidance from the National Institute for Health and Care Excellence (NICE).

It is recommended that the medication be used in tandem with a reduced-calorie diet and increased physical activity.

You are eligible for Wegovy if you meet the following criteria:

  • Have a Body Mass Index (BMI) of at least 35

  • One weight-related comorbidity (such as hypertension of cardiovascular disease)

  • Have a BMI of 30 to 34.9, provided you meet the criteria for referral to specialist weight management services

The Department for Health and Social Care adds: "Wegovy is for those dealing with obesity and weight-related problems, not for people who just want to lose some weight."

Wegovy is taken via an injection once a week. Should you meet the eligibility criteria and are prescribed Wegovy, your healthcare team will give you more information about how to take it and how to inject it.

Mounjaro is approved for weight loss and weight management in adults aged 18 and over who meet the eligibility criteria. It works by regulating a person’s appetite so they feel full, making them feel less hungry and experience fewer food cravings.

It is recommended that Mounjaro be used together with a reduced-calorie diet and increased physical activity.

You are eligible for Mounjaro if you meet the following criteria:

  • Have a BMI of at least 30

  • Have a BMI between 27 to 30, and weight-related problems such as prediabetes, high blood pressure, high cholesterol, or heart problems

Mounjaro is available as a pre-filled injection pen that is to be injected under the skin of your stomach area, thigh or upper arm. The starting dose is 2.5mg once a week for four weeks, increasing to 5mg once a week.

According to the Medicines and Healthcare products Regulatory Agency (MHRA), the dose may then be increased in at least four-week intervals up to the maximum dose of 15mg per week.

Women using oral contraceptives may be advised to consider using a barrier method of contraception, such as a condom, or switching to a non-oral contraceptive method for four weeks after starting Mounjaro. This is because Mounjaro may affect the efficacy of the contraceptive pill.

You can get both Wegovy and Mounjaro via a private prescription in the UK. Neither medication is available over the counter from a pharmacy, as you will need to be assessed for suitability before being given a prescription. You should also get ongoing support from the prescriber.

However, the National Pharmacy Association (NPA) warned last year of a possible "explosion in the unlicensed sale of medication online" and urged people not to take the risk of buying weight loss injections without proper checks.

The NPA advised patients to speak to their GP about whether they are eligible for and should have a prescription for weight loss drugs. The warning came after the MHRA reported that nearly 50 people were hospitalised after using weight loss drugs last year.

The MHRA said prescription-only medications such as Wegovy and Mounjaro are "effective and acceptably safe when used within their licensed indications", adding that there are still "risks associated with their use”.

"When appropriately used in line with the product license, the benefits of these medications outweigh the risks for patients," said the regulatory agency. "However, this benefit-risk balance is positive only for patients within the approved indications for weight management or type 2 diabetes as described in the product information."

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