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Weight loss injections/treatments

Discuss weight-loss injections and treatments, including personal experiences. Mumsnet hasn't checked the qualifications of anyone posting here. You may wish to speak to a medical professional before starting any treatments.

Feel awful

25 replies

Shootingstar1111 · 11/02/2026 17:36

I did 4 weeks on 2.5, felt great, good weight loss. I took my first dose of 5mg on Sunday evening and felt ok, then the early hours of Tuesday morning I had horrific stomach cramps, diarrhoea and vomiting. This lasted about 6 hours. I felt rough yesterday and continued to have diarrhoea. Then again at 1am this morning I started being sick with stomach cramps and I feel awful.
has anyone else had similar after increasing their dose?

OP posts:
MJagain · 11/02/2026 17:47

It’s a well known side effect. Many threads on here.

SilenceInside · 11/02/2026 17:51

Yes, it’s often associated with moving up a dose. I had similar on 5mg and to a slightly lesser extent when moving up to 7.5mg. It’s listed in the side effects as a common side effect which affects around 1 in 10.

There’s some good advice in this article from Asda Online Doctor:

https://onlinedoctor.asda.com/uk/mounjaro-side-effects.html#8_Managing_Mounjaro_side_effects

Aliceisagooddog · 11/02/2026 17:54

I would move back down to 2.5mg. Where u being careful to avoid fatty foods? That's whst always gave me the worst symptoms.

PurpleCoo · 11/02/2026 18:02

Curious as to why you increased the dose when you have had good weight loss? I stayed in 2.5 until I felt it wasn't working as well, and then went up to 3.75 and then stayed there until I felt it wasn't working as well.

You have doubled the dose when the lesser dose seemed to be working ok, so I am not surprised you are having lots of side effects. I hope it doesn't last long for you and you feel better soon, but I would consider taking a lower dose next time

Have you modified your diet? I.e. avoiding known food triggers such as fatty food?

Gollumscat · 11/02/2026 18:07

What have you eaten? I had chips once and was so ill I haven't touched anything fried since, also the amount? Tried going past the feeling of fullness once and was violently sick in the night, horrible (tmi) undigested food, also going up to 5, it's very common to get awful side effects, I increased to 3.75 before I tried 5 after a couple of months on 2.5.

susiedaisy1912 · 11/02/2026 18:15

Were you loosing weight on 2.5mg? No need to rush up the doses unless you are stalling on the dose you’re on. I’ve lost 6 stones so far and I’m still only on 7.5mg. And to answer your question yes when I went from 2.5 to 5 in one leap I ended up in A&E as I was so unwell. So I have always crept up the doses much slower 2.5 then 3 for a few weeks then 3.5 etc.

Rainraingoawaydontcomeback · 11/02/2026 18:21

I agree with other, if you have good weight lose you shouldn’t move up a dose. You can count the clicks to move back down to 2.5 from your 5 pen.

Have you taken any medication to help with you’re effects? Immodium, gaviscon and electrolytes would be my go to.

Shootingstar1111 · 11/02/2026 18:29

To be honest I ordered the 5mg because I thought that was what you were meant to do after 4 weeks on 2.5. My friend had a code so I ordered it 2 weeks into 2.5. If I had waited then I would have ordered 2.5 again.
I’ve honestly never felt so ill. Doesn’t help I’m full of a cold too! Im just drinking as much as I can.
if I go to 2.5 counting clicks I will run out of needles, where can I get some more?

OP posts:
putthehamsterbackinitscage · 11/02/2026 18:29

Pepto bushel might help with symptoms, and I would say go back down in dose first now - in a few days once your levels have dropped you should be back to where you were.

Then take a couple of weeks to let things settle before either graduallly increasing using interim dose by counting clicks, or you could jab more frequently (split dose) so as to keep levels more constant and avoid spikes.

see thread on split dosing for more info.

LifeisLemons · 11/02/2026 18:37

You can buy a boxes of 100 needles from your local pharmacy or online.

I’ve been on MJ since September and still only taking 3.75mg from a 5mg pen.

Did you join the January starters thread? The other posters will be at about the same point as you and very few will have moved up to 5mg.

I’d definitely drop back to 2.5mg if it was still working for you. It’s 30clicks of a 5mg pen. Look up click counting if you’re unsure.

JHound · 11/02/2026 18:44

Oooh this scares me - I have a shooting event nex weekend which wbe my first weekend on 5mg - I hope I don't get severe side effects. I debated staying on 2.5mg but it honestly did next to nothing for me. Saiety as slightly better in the first two weeks but my appetite is not really changed. I am heading into my 4th week and felt masively hungry this week (although my period is due).

Hang on in there!

Gollumscat · 11/02/2026 18:58

I think the more sensitive to it you are the worse the side effects seem to be, I was very sensitive to 2.5 and only really went up because I thought I should, although I only went up to 3.75, and then 5 for a couple of weeks lost over 5 stone on lower doses, but it's a case of being mindful of your own body and how you're tolerating the doses much more than what the protocol is.
I would say don't up doses if you're not comfortable with that, don't be pushed into it by the prescriber, obviously if you aren't responding anymore and you're not losing weight time to up the dose but if you're OK then stick to your dose or increase by a smaller increment than 2.5 to test the waters.

Tammy214 · 11/02/2026 19:14

it sounds like it could have been a combination of things if you also have a cold.
I had no big issues on 2.5,5, and then 7.5 i felt rough and i did question if i should have gone up.
However when i started researching, its to be expected on some dosages and very well known on the step up to 7.5. However the suppression wasnt great on 5 so whilst i delayed the 2nd dose of the 7.5 and that was fine.
So really i decided that i will go up to 10 next time as i want to get the maximum benefit out of this, and this is the compromise. if i had not improved or wasnt able to eat by the 2nd-3rd day, and feeling pretty normal by 4th i would be nervous of having the next jab.
It seems alot of people stick to 5, which is fine if your getting what you want from the drug, but if your not then perhaps thats the pay off?

newmenewwhatever · 11/02/2026 19:22

I had the same problem this week on 5.
i was wondering if where you Inject has a baring on side effects?!

Daisywhatsyouranswer · 11/02/2026 21:36

I’d similar on 5 the first week, not so bad, second week still icky but less so, third week fine. Many feel unwell when they move to five, but it settles down.

PearlTeapot · 11/02/2026 21:47

I was the same when I tried 5, I then dropped to 3.75 the following week and was just as unwell. Take lots of liquids for dehydration if you can, I wish you better.

I bought the pen needles from Uk Medi which I recommend.

I’m now at 4 stone loss and am now taking 3.33.

SquishyGloopyBum · 11/02/2026 22:00

its the biggest jump when you up doses as you are doubling it. I stuck with 3.75 (45 clicks) for a good while before then going up.

Springbaby2023 · 12/02/2026 00:50

I have very similar side effects currently at it is absolutely horrific. Really hoping it eases tomorrow. I am on 7.5mg (took my second dose Monday) but will be dropping back down after this experience as nothing is worth how I’m feeling right now!! Interestingly though I’ve also had a cold, I wonder if that is making everything worse for us both.

Springbaby2023 · 12/02/2026 00:52

@Tammy214 Did you just get that after your first 7.5? I was ok after first 7.5, just some usual tiredness, but this second one has knocked me for six I feel so ill with cramping, D&V.

Shootingstar1111 · 12/02/2026 11:58

I slept for 12 hours last night and feel a lot better today, still a bit rough but nothing like I have been. I’ll be sticking to 2.5mg from now on, nothing is worth feeling like that!!

OP posts:
Tammy214 · 13/02/2026 12:06

my first 7.5 i felt rough and was travelling so awful as i wasnt eating and felt a bit sick, i didnt start feeling like i could eat until the 3rd day. I had the 2nd jab and felt a bit queasy the first day or so but been fine but a very low appetite, i feel ok now and its the 3rd day.
I am likely to go up to 10mg next order as am feeling ok after the first 48 hours which apparently is expected.

I would persevere with it, it sounds like you have a combination of being ill and then the side effects of the jab. you might want to delay the jab until your feeling 100% because if you go back to 2.5 it slows down your potential losses and likely it will mean you wont benefit from the full benefits of the drug, 5 is the first full dosage.obvs thats my opinion, i know what its like to ahve those symptoms with past medications, but it can be hard to get back on the horse but sometimes knowing thats the worst it will get means we can get past it

LifeisLemons · 14/02/2026 12:43

@Tammy214 How will going back to 2.5mg slow down her losses exactly? Or are you just making stuff up?

Noominia · 14/02/2026 12:50

I had exactly the same when I went from 2.5 to 5. I dropped down to 4 and then went back up to 5 with no problems a couple of weeks later, it sounds as though maybe you could drop back even further. On the upside, after that rough period was over I suddenly realised that I had lost a good chunk of weight and my body was looking quite different. That was a real psychological boost and since then the loss has been much slower and steadier.

TheActualQueen · 14/02/2026 18:56

Shootingstar1111 · 11/02/2026 18:29

To be honest I ordered the 5mg because I thought that was what you were meant to do after 4 weeks on 2.5. My friend had a code so I ordered it 2 weeks into 2.5. If I had waited then I would have ordered 2.5 again.
I’ve honestly never felt so ill. Doesn’t help I’m full of a cold too! Im just drinking as much as I can.
if I go to 2.5 counting clicks I will run out of needles, where can I get some more?

You can buy needles online op. pharmacies like medexpress hace them.
I have just had severe vomiting from going up to 5mg last month, even after doing a couple of 3.75’s. Going back down to 2.5 this week.

Wallywobbles · 14/02/2026 19:05

I did half doses of the new one every time so 3.75 using the syringes recommended on every MJ thread. Did it at every dose increase. Also spent 3 months at each dose.

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