How Long Will Mounjaro Be Out of Stock? (October 2026)

01 · The honest answer

How long will a Mounjaro stock gap last?

A gap at one pharmacy may reflect that pharmacy's own ordering rather than a national problem, so the practical answer is to check another supplier the same day.

We source Mounjaro through official LillyDirect supply, direct from Eli Lilly's UK distribution, and stock all six doses. Right now they are in stock. You can check live availability and prices on the Mounjaro pen page.

02 · Next steps

What to do if your dose is unavailable

Speak to your prescriber first, because the right move depends on where you are on the dose ladder. Everyone starts on 2.5mg; the dose rises after at least 4 weeks to 5mg, then in 2.5mg steps at minimum 4-week intervals, up to 15mg.¹ Your prescriber can advise on timing and whether any change is appropriate.

Our guide on what to do if Mounjaro is out of stock goes further, and if your gap is at a specific strength, see whether 10mg is out of stock.

03 · Switching provider

Switching provider mid-treatment

If you move to us at any dose, you start with a free online consultation reviewed by a GPhC-registered prescriber. New customers save £40 on their first order with code FIRST40, and an automatic £25 reorder discount applies to every future order (code DOSE25). You can start your free consultation online; same-day dispatch applies when ordered by 3pm, with free next-day tracked delivery.

Related guide: Mounjaro Before and After 1 Month.

04 · If you miss a dose

If a gap makes you miss a dose

Take a missed dose as soon as you can within 4 days (96 hours) of the scheduled time, then carry on as usual.¹ If more than 4 days have passed, skip it and take the next dose on your normal day. Never take two doses within 3 days of each other.¹³

You can also change your injection day, provided at least 3 days (72 hours) have passed since your last dose.¹

05 · Why not stretch doses

Why you should not stretch or split pens

Stretching or splitting pens is not licensed and not supported by the pen's design or any UK regulator. It means unknown dosing accuracy and no safety data.

06 · Stopping and clearing

What happens during a longer break

Tirzepatide has a half-life of about five days, so after a final dose it takes roughly 4–5 weeks to clear the system. There is no way to speed this up.¹

If a break is likely, talk to your prescriber about how to restart safely rather than resuming at your old dose yourself.

07 · Storage of pens you hold

Storing pens while you wait

Keep pens in a fridge at 2–8°C and never freeze them. Once in use, a pen can stay out of the fridge not above 30°C for up to 30 days, then it should be discarded.¹ Unopened pens keep until the expiry date on the box. For an unopened pen that has been out of the fridge, check with the pharmacy before using it. See our guide on how long Mounjaro can be out of the fridge.¹³

08 · Price and counterfeit risk

Shortages, prices and counterfeit risk

Across the UK pharmacies we track, Mounjaro pens range from £143.96 to £339.00 (checked 11 October 2026). Read more on how much Mounjaro will be.

Gaps are when scams appear. Only buy from a registered pharmacy and be wary of anyone offering to supply without a consultation or prescription. The MHRA publishes counterfeit alerts and runs the Yellow Card scheme.⁷ You can verify us on the GPhC register (9012878).¹²