Mounjaro stopped working for me at 7.5mg. plateau, side effects. Has anyone been here?
Started Mounjaro on 1 July 2025 at 215 lbs. Here’s the timeline as clearly as possible because I’m trying to work out whether the issue is the medication interruptions, the dose changes, or whether MJ just may not work as effectively for me long term. I thought it was finally going to help me.
For context, I’ve struggled with my weight since around 2021 and it’s been incredibly resistant to shifting consistently, which is why starting MJ felt like such a big change initially.
2.5mg (July–August):
Weight steadily trending down with no significant side effects.
5mg (September–November):
Continued losing consistently. By late November I was around 195–199 lbs, so roughly 16–20 lbs down from my starting weight.
7.5mg (late November/December):
Weight continued dropping and I reached my lowest around January at 192–193 lbs.
December break (~2 weeks):
Had an unplanned gap because I bought my next pen late.
January restart at 7.5mg:
This is where things changed. For about 3 consecutive injections I had severe vomiting after each jab, so I stopped again for roughly 3 weeks.
Late February restart at 5mg:
Restarted lower because I was nervous about the side effects. Since then my weight has mostly fluctuated between 194–204 lbs without any real sustained downward trend.
A few other factors:
• I’ve had a pretty stressful few months personally/work-wise.
• I started therapy around December and have been processing some heavier things emotionally.
• My eating habits are honestly better now than they were in my first 6 months on MJ, which is part of why the stall has confused me.
• I exercise regularly (including spin) and my muscle mass appears to be increasing slowly. (Last year I mainly walked and occasionally Pilates at home. But when weight stopped moving I started netball for 6 weeks this year, started HIIT once a week and weight training 2x a week).
• Appetite suppression feels less consistent now than it did earlier in the journey.
• I haven’t calorie tracked consistently, so I’m open to the possibility that’s contributing too.
My questions:
• Has anyone had severe side effects after a break, then successfully gone back up to a higher dose later?
• Did dropping back down from 7.5mg to 5mg significantly reduce effectiveness for you?
• Has anyone experienced long stalls after interruptions and eventually started losing again?
• Does this sound more like a protocol/interruption issue than the medication “failing”?
I have about 9 years of weight/history data so I can clearly see the shift when things became inconsistent. Looking for responses from people who’ve actually navigated something similar rather than generic advice