Mounjaro Can I get a 2.5mg dose from a 5mg pen?

[Mittens67]

I want to stay on 2.5mg longer so can I use the 5mg pen I have ready to move up to for a 2.5mg dose instead? And if so how?

Won't any secure seal be broken if you do that and possibly introduce infection?

Yes you can take half the dose by counting 30 clicks when you're turning the bottom of the pen

Yes you can, but you need to stick with the guideline to use the pen within 30 days of the first use. So you could get 5 doses of 2.5mg out of it within that timeline. You would do 30 clicks to get a 2.5mg dose from a 5mg pen. It would waste a fair amount of the medication. Would it not be more cost effective to keep the 5mg pen assuming it's in date for a good while longer, and just order another 2.5mg pen and use that. Then use the 5mg pen when you are ready to move up doses.

30 clicks for a 2.5mg dose from 5mg pen.

If the cost of the 5mg is not much different from the 2.5mg, it means if you feel you want to move up mid month you have the flexibility to increase to 5mg (or less) on any week. There will be medication to discard at the end of the pen, but I try not to think of it as wasted if I got the effect I wanted for those weeks.

After 5 weeks on 2.5mg I have been on 3.75mg (45 clicks) for 12 weeks now and it is still working well.

Does anyone know if 35 clicks is just under 3mg if I've worked that out correctly?

36 clicks is 3mg from a 5mg pen.

30 clicks is 2.5mg from a 5mg pen.

So yes, 35 clicks is just under 3mg, by a tiny amount!

Thank you @HippoPortlyMouse I don't know why I didn't think of 36 clicks 😂 x

Thank you everyone

It’s absolutely fine to keep the pen for more than 30 days once open. Just use the alcohol swabs and keep it in the fridge.
I’ve used 5mg pens to give myself 2.5mg ( 30
clicks) for 10 weeks ( counting the bonus dose) .

You sound certain, where did you get that information? When prescribers have reached out to Eli Lilly, they’ve been firm and consistent about discarding after 30 days from first use due to medication stability.

I’ve gone slightly over the 30-day mark myself, but doubling to 10 weeks seems excessive unless there’s at least some knowledge about the potential risks involved. I worry people minimise the risks of this medication, as it is "only" for weightloss and relatively easily available, when it is making some quite powerful changes to your hormones that control blood sugar or metabolism.

The risk might be low, similar to the low risk of reusing a needle, and up to each individual to decide on if they want to accept that risk, but if that risk does materialise, it could lead to harm.

I was thinking what previous person has said.. where did you find info saying 10 weeks was OK? . In that case why don't you get a 10mg or 15mg and make it last weeks and weeks..

Hi I have a 7.5 mg pen but only want to use 5 mg as the first dose was to strong for me how do do this please xxx

@Hev1111 5mg is two thirds of 7.5mg, so you would need to do two-thirds of a normal dose. A normal dose is always 60 clicks on any strength pen. Two-thirds of 60 is 40, so you would turn your 7.5mg for 40 clicks instead of all the way to the 1 position.