If you’ve read the tabloids in the past few months, chances are you’ve heard of a new class of medications being used for type 2 diabetes and weight loss. This class of medications, referred to as GLP-1s, include a number of different brand names, but you’re most likely to be familiar with an injectable GLP-1 called Ozempic. In this article, we’ll explain what GLP-1s are, how they work for blood sugar control and weight loss, and dive into a few of the different versions that you may come across.
What are GLP-1s and how do they work?
GLP-1 (glucagon-like peptide-1) medications are a type of drug originally used to treat type 2 diabetes. They work by mimicking the effects of the naturally occurring hormone GLP-1, which helps to regulate insulin production and lower blood sugar levels. GLP-1 medications can also slow down the rate at which food leaves the stomach and can lead to weight loss—in fact, they are so effective at inducing weight loss that some GLP-1 medications have recently been relicensed for weight management, whereas previously they were only available for treatment of type 2 diabetes.
Within the GLP-1 category, there are a few different types of compounds, including semaglutide, liraglutide, dulaglutide, and a number of others currently being developed. As with most medications, however, the brand names used for marketing are different to the compound name, so chances are you’ll be more familiar with the brand names.
Brand name examples of GLP-1 medications include Ozempic (semaglutide), Wegovy (semaglutide), Victoza (liraglutide), Trulicity (dulaglutide), Bydureon (exenatide extended-release), and Rybelsus (oral semaglutide).
Semaglutide: A GLP-1 that’s become common for weight loss
While the GLP-1 class of medications has been around for years for the treatment of type 2 diabetes, it’s only recently that semaglutide, Ozempic, and Wegovy started gracing the pages of news sites.
Let’s first understand the difference between these three terms, as medication names can quickly start to feel a bit like alphabet soup.
Semaglutide is simply the compound that both Ozempic and Wegovy contain. Ozempic is the brand for semaglutide that’s marketed for type 2 diabetes—Wegovy is the brand for semaglutide marketed for weight loss. What’s actually inside both medications is the exact same compound! The only difference (and this will become relevant as you continue reading) is that the maximum dose for Wegovy is 2.4 times higher than the maximum dose for Ozempic.
What the research evidence now seems to suggest is that, at higher doses, semaglutide medications are more effective at inducing weight loss. Research evidence on the efficacy of higher dose semaglutide was only published in 2021, which in part explains why we’ve only recently started talking about these medications for weight loss as opposed to for type 2 diabetes.
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Can you take Ozempic for weight loss?
As mentioned above, Ozempic is semaglutide marketed for type 2 diabetes—which means it is meant to be prescribed for people with type 2 diabetes. However, ever since Wegovy was approved for weight loss, there has been some blurring of the lines between the two medications.
The first thing to understand is that “off-label” prescribing is a relatively common and accepted practice amongst prescribers. Off label means that the prescriber wants their patient to use it in a different way than that stated in its licence. This could mean using the medicine for a different condition or a different group of patients, or it could mean a change in the dose or that the medicine is taken in a different way. Off-label prescribing is sometimes used for cancer treatment, for example, as some cancer drugs are licenced for a specific type of tumor, but may also be effective on other types. Someone prescribing a medication for one of these “other” types would be doing so off label.
Once Wegovy was approved for weight loss and patients started seeing how powerful the medication could be, supply issues started cropping up as the manufacturer of Wegovy wasn’t expecting such high amounts of demand, particularly in the US. As patients were still keen to access the medication for weight loss, some doctors started prescribing Ozempic off-label to patients without type 2 diabetes.
In the UK, NICE has issued draft guidance for the licensing of Wegovy, however at present Wegovy is not available in the UK. That has meant that, similar to in the US, some people in the UK have gotten Ozempic (which is currently available) prescribed off-label.
Should I take GLP-1 medication for weight loss?
The ultimate decision as to whether or not to take a medication is one that you'll need to make, alongside advice from your doctor. If you're considering taking a medication like Ozempic, however, there are some important considerations to take into account:
- GLP-1 medications are meant to be taken alongside a healthy diet and exercise routine, so they're not a quick fix. You'll need to put time and effort into rethinking your relationship with food in order to make lasting change and keep the weight off for good.
- Medications like Ozempic and Wegovy may result in side effects in some people, including primarily gastrointestinal effects such as nausea and vomiting. If you do decide to take a medication for weight loss, it's important to be aware of potential side effects, and seek medical help if they become unmanageable.
- Wegovy is not currently available in the UK, so if you'd like to try out semaglutide for weight loss you'll need to get Ozempic prescribed off-label.
 N Engl J Med 2021; 384:989-1002DOI: 10.1056/NEJMoa2032183 Accessible here