What are GLP1 and GLP1/GIP Agonists? A word about Wegovy/Ozempic and Zepbound/Mounjaro.
There are several different types of weight loss drugs currently on the market. They all work in some form to decrease appetite or cravings. The most effective FDA-approved weight loss drugs are the GLP1 and GLP1/GIP agonists. These are the medications that are getting a lot of press right now, Wegovy, Zepbound, Ozempic and Mounjaro. These medications mimic a gut hormone that responds to food. They are responsible for the so-called “Incretin effect” that has several functions in the body. GLP1 agonists regulate blood glucose by regulating your natural insulin and glucagon production, they also slow down gastric emptying (slow transit in the gut). They are excellent drugs for diabetes, but they always work in response to the sugar that is there, so if you are not high, they will not make your sugar crash. They can be used in people with no history of diabetes or insulin resistance. These medications also work on the hunger center in the brain. They shut down the hunger signal, patients experience earlier satiety (fill up faster), and reduced cravings. Many patients describe it as “reduced hunger noise”.
Contrary to popular belief, these drugs are not new. The first GLP1 agonist, Exenatide (Byetta) was approved for treatment of Type 2 Diabetes in 2005. Byetta is a twice daily injection that did have on average more side effects. Over time, newer and more effective GLP1 agonists have been developed. Liraglutide was approved for diabetes as Victoza in 2010, and then for weight loss as Saxenda in 2014, this was the first time any GLP1 agonist was approved specifically for weight loss.
In more recent years, we have seen a big leap in these medications, including the approval of Ozempic (semaglutide) for diabetes in 2017 and then Wegovy (also semaglutide) for weight loss in 2021. Ozempic soon proved to be more effective than any of its predecessors for both diabetes and weight loss. Wegovy has on average about 15% weight loss. In 2022, Mounjaro was approved for diabetes. It is slightly different from the others in that it is our first combination drug molecule, GLP1 and GIP, two hormones that work the same way and have a synergistic effect, boosting for strongest results. After long-anticipation, it finally received weight loss approval as Zepbound in November of 2022. Zepbound and Mounjaro show an average of 22% weight loss.
Both Wegovy and Zepbound are excellent medications for weight loss. This category of drug has shown to have other benefits as well, studies with Ozempic/Wegovy have shown reduced risk of heart attack and stroke, as well as improvement in kidney function. Mounjaro/Zepbound is newer, but they are currently undergoing research that will likely show comparable results.
When used correctly, these medications are safe and can be very effective. They are not a quick fix and should not be used to “jump start” a diet or to lose those last ten pounds. They are best used as a long-term therapy. They help to get people off that roller coaster of weight gain and loss to allow for more permanent change.
These medications are most successful when combined with lifestyle modification and counseling. Your best bet at weight loss and improving your health is to sit down with a board-certified weight loss physician (Diplomate of the American Board of Obesity Medicine) that can evaluate you and work with you to produce your ideal treatment plan.