Where people notice differences

Here’s where things get interesting. Many users say Mounjaro feels “heavier” on appetite, almost like it presses a stronger brake on hunger. That can be a win for weight loss, but it sometimes comes with more intense nausea or fatigue, especially in the first weeks of a new dose.

Ozempic, on the other hand, is often described as a little gentler. People sometimes say it’s easier to tolerate, though they may also notice cravings creeping back in sooner between doses compared to their time on Mounjaro.

Neither description is universal. For every person who found Mounjaro rougher, there’s another who felt Ozempic knocked them harder. The variation is huge, which is why prescribers always say individual response matters more than averages.

Side effects that tend to surprise

Some things aren’t in the glossy leaflets but pop up again and again in user stories. Burping is one, and both drugs can bring on loud, unexpected belches that seem to come out of nowhere. Another is the way taste and smell can shift. Suddenly, a favourite food might smell off, or something you never fancied before becomes oddly appealing.

These quirks can happen on both drugs, but people often say they showed up differently. On Mounjaro, it might be an intense aversion to richer foods. On Ozempic, it could be a subtle change in taste that makes portion control easier without thinking about it.

How long do side effects last?

Most side effects are dose-related and tend to fade once your body adjusts. That’s why prescribers start low and increase slowly; it’s not to frustrate you, it’s to give your system time to adapt.

With both Mounjaro and Ozempic, many users report that nausea and bloating are at their worst in the first couple of weeks on a new dose, then ease off. Constipation, however, can linger if diet and hydration aren’t adjusted alongside.

It’s a very common experience for side effects to flare again when switching from one drug to the other. Even if you’d “settled” on Mounjaro, moving to Ozempic can feel like going back to week one for a short while. The same is true in reverse.