Weight Loss Injections: The Science

How do weight loss injections work?

What is GLP-1?

GLP-1, or glucagon-like peptide-1, is a hormone that helps regulate blood sugar levels. It's produced by the body after eating, and it helps the body produce insulin, reduce sugar production, and slow digestion. GLP-1 also helps people feel full and reduces appetite

GLP-1 receptor agonists (GLP-1RAs) are a class of drugs that mimic GLP-1's actions and are used to treat type 2 diabetes and obesity. GLP-1RAs can be taken as injections or tablets, and they work by:

  1. Helping the body produce more insulin

  2. Reducing the amount of sugar produced by the liver

  3. Slowing down digestion

  4. Reducing appetite

Is it effective?

GLP-1 medications have been produced for over a decade, with a number of wide-scale, long-term studies proving its efficacy. One key study, involving 1,961 people, people treated with Wegovy were able to lose on average 15% of their body weight after 68 weeks compared with a 2% loss of weight in people who had placebo (a dummy treatment). In addition, 84% of people in the Wegovy group were able to lose at least 5% of their weight compared with 31% of people in the placebo group.

What GLP-1 drugs are available?

Ten GLP-1 drugs are FDA-approved to treat either type 2 diabetes or weight loss. Some GLP-1 agonists have the same generic name but are marketed under a different brand name and are approved for a different purpose, depending on the dose and how they are taken.

How long do weight loss injections take to work?

GLP-1 medications start working straight away, and most patients start feeling fuller within the first few days of taking it. You should start seeing noticeable improvements to your weight within 5-6 weeks. Speak to your doctor if you don’t see any weight loss results within 6 months of taking Wegovy, as it may not be the right option for you in that case.

How long does the medications stay in your system?

GLP-1 medications stay in your body for 5-7 weeks after your last dose. This medication is a long-acting medication, which is why you only need to take 1 dose a week for it to be effective. Because of this, it takes a longer period of time for it to be fully removed from your body. You may find during this time that your appetite is lower than usual, but it should return to normal 5-7 weeks after your last dose.

Backed by science

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