Speed of Appetite Reduction by GLP-1 Medications

In the ongoing battle against obesity, two new medications, semaglutide (WegovyTM) and tirzepatide (Zepbound®), are making waves. Known as GLP-1 agonists, these drugs mimic the gut hormone GLP-1, which is naturally produced in the intestines and brain, and can help with insulin response, body weight control, and slowing stomach emptying.

The effects of these medications can be felt within the first few days, with changes in appetite or side effects like nausea, vomiting, or diarrhea. However, the initial dose may not have any immediate effect, and the full benefits may not be seen until several months into the treatment as the drug doses are adjusted.

Continuing lifestyle modifications, such as improving sleep, a healthier diet, or physical activity, can help GLP-1s work their best. Research shows a connection between how a person initially responds to GLP-1s and how it may benefit them long-term.

Typical effective doses for weight loss are around 2.4 mg once weekly for semaglutide, and tirzepatide doses for weight loss typically range from 5 mg up to 15 mg once weekly, adjusted based on tolerance and efficacy. These doses have been shown to achieve significant weight loss in most people.

Ongoing research will continue to shed light on how fast GLP-1s work, but it's clear that if a person responds well to GLP-1s initially, they may benefit from it long-term. If a person loses more than 5% of their body weight in the first three to four months on an obesity medication, they are more likely to maintain that body weight after 12 months. A recent study with tirzepatide shows that if someone loses 10% or 15% of their body weight by six months, they are more likely to keep it off after one year.

Each person's response to the medication can vary, and factors that can influence how fast it starts working include diet, exercise, metabolism, menstrual cycle, sleep, and stress levels. A change in appetite may not be noticeable after the first dose and may take several weeks to become apparent.

While these medications offer a promising new tool for managing obesity, it's important to remember that they should be used as part of a comprehensive weight loss plan that includes lifestyle changes and regular medical supervision. As always, consult with a healthcare professional before starting any new medication.