Getting started
If you're weighing your options, the conversation almost always comes down to two medicines: semaglutide and tirzepatide. A handful of others exist, but these two have the deepest clinical evidence and the largest pool of real-world experience behind them right now.
Semaglutide
Sold under the brand names Ozempic and Wegovy, semaglutide acts on the GLP-1 receptor. It dials down appetite, slows how quickly your stomach empties, and helps regulate blood sugar. In the STEP trials, participants lost an average of roughly 15% of their body weight over 68 weeks.
Tirzepatide
Marketed as Mounjaro and Zepbound, tirzepatide layers GIP receptor activation on top of the GLP-1 mechanism. That dual action showed up in the SURMOUNT trials as an average body weight reduction of around 20-22%. Interestingly, the second pathway also seems to ease GI side effects for some people compared with GLP-1 alone.
Give it time - this is the part most people get wrong
Here's something worth setting expectations around early: many people don't see meaningful weight loss until they reach the top one or two doses. The lower doses you start on aren't really there to drive results - they exist to let your body acclimatize to the medication while it builds to a steady state. Climbing to those higher doses is deliberately slow, and it can realistically take three to four months to get there.
Almost every day, someone arrives two weeks or a month in, frustrated that nothing has happened, asking whether they should switch medications, quit, or jump to the next dose ahead of schedule. Far more often than not, the issue isn't the drug - it's that the expectation was set too high, too soon. Those first couple of low doses simply aren't therapeutic doses; they're titration steps, meant to give your body room to adjust before the medication reaches the level where it actually does its work.
Practical considerations
- Both need a prescription. Neither is something you start on your own.
- Brand versions are pricey if you're paying out of pocket without insurance.
- Compounded versions through licensed pharmacies are far more affordable and accessible. That said, the FDA has been actively revising its stance on compounded GLP-1s, so check the current status before going that route.
Side effects
For both medicines, the side effects are mostly gastrointestinal - nausea above all, and especially during the titration phase. Both can also cause muscle loss alongside fat loss, which is worth getting ahead of with adequate protein and resistance training.
A note: none of this is medical advice, and I'm not a doctor. This is just one person who read a lot and wanted to organize it in a way that might help. Always make decisions with a qualified physician.