If you miss one Mounjaro or Wegovy injection, follow the leaflet rule for your product. Mounjaro allows four days late and Wegovy five. Several missed doses or a longer break need a prescriber to review your restart. Write down the date of your last dose. A prescription, order or delivery date does not replace the dose date.
Which kind of treatment gap do you have?
Work out which kind of gap you have before you ask for advice. Each kind needs a different answer:
- One late or missed injection: follow the missed-dose rules for your exact product.
- Several missed doses or a longer break: ask your prescriber (the doctor, nurse or pharmacist who approves your medicine) whether and how to restart.
- A delivery problem: tell the clinical team when your next dose is due and how much medicine you have left.
- A planned change of injection day: follow the day-change rules for your product.
- A change of medicine or form, such as pen to tablet: this needs its own prescribing plan, separate from any gap sum.
This page covers adult UK weight-loss treatment. Use the page to prepare. The page gives no personal restart plan. If you stopped because of symptoms, or a clinician told you to pause, get advice. Do not treat this pause like a forgotten dose.
Missed one Mounjaro or Wegovy injection: the leaflet rules
| Medicine | How late? | What the leaflet says |
|---|---|---|
| Mounjaro | Four days or less after the due date | Take the missed dose as soon as you remember, then go back to your usual weekly day. Leave at least three days between doses. |
| Mounjaro | More than four days after the due date | Skip that dose and take the next one on your usual day. |
| Wegovy injection | Five days or less after the due date | Take the missed dose as soon as you remember, then take the next one on your usual day. |
| Wegovy injection | More than five days after the due date | Skip that dose and take the next one on your usual day. |
Never take a double dose to make up for a missed one. Count the days from the date the missed injection was due. Your order date does not count. Check the Mounjaro patient leaflet or the Wegovy injection patient leaflet for your pack. If you are unsure of the dates, ask the pharmacist to check them with you.
How to change your weekly injection day
Leave at least three days between injections when you change day. The Mounjaro leaflet sets a minimum of three days between injections. Wegovy’s prescribing information asks for at least three days, set out as more than 72 hours, then weekly doses. Check the Wegovy day-change rules.
These minimum gaps do not let you inject more often as a habit. If a late dose and a day change overlap, ask your pharmacist for the exact dates.
Restarting after two or more missed doses or a longer break
Contact your prescriber before you restart. Do not go back to an old high strength because you still have a pen or an old prescription. Wegovy prescribing information says a lower starting dose should be considered after several missed doses. The same information gives no single restart answer for every length of break.
NICE’s tirzepatide restart guidance asks clinicians to look at why treatment stopped and how you responded before. After some side effects, a slower build-up may suit you. Confirmed pancreatitis is a reason not to restart. Tell the team why you paused, as well as how many days the break lasted.
Ask for the plan in writing: the restart strength, first dose date, later schedule and follow-up. If you need a different strength, ask how the pharmacy will correct any order still waiting to go through. Do not place another order while you are unsure what has been prescribed or sent.
How a pharmacy measures a gap in your records
A pharmacy may count your gap differently from you. MedExpress’s published gap policy counts from the previous prescription date to the new order date. This figure differs from the number of days since your last injection. The MedExpress review can change your dose. Do not treat the MedExpress policy as a general restart rule for other pharmacies.
The difference matters when you switch pharmacy. A month with no order at one pharmacy may include an order from another. A recent delivery does not prove you used the medicine either. Give the new pharmacy your order history and a record of the doses you took, with proof where you have some.
For example, a prescription dated 1 September, a delivery on 3 September and a last injection on 24 September are three separate facts. Write each one under its own heading. The example shows how to keep records. The example is no restart advice.
If you switch pharmacy every month to pay the new-customer price, keep this record up to date for every move.
Missed Wegovy tablet: different rules from injections
If you miss a Wegovy tablet, leave out the forgotten tablet and take the next one the following day. This rule comes from the UK Wegovy tablet prescribing information. The four-day and five-day injection windows do not apply to daily tablets. Foundayo and other products need their own current leaflet and your prescriber’s instructions. The injection table above does not cover them.
Give the full brand, form and strength when you contact a new pharmacy. “Wegovy” on its own does not say whether you mean tablets or injections. The pharmacy then cannot tell which rules apply.
What to do if a pharmacy switch delays your next dose
Start the new consultation at least a week before your next dose is due. If a delay still happens, take these steps:
- Contact the new pharmacy before your next dose is due. Say whether your consultation is complete and when your current medicine runs out.
- Send real treatment evidence quickly through the team’s secure channel. Ask whether anything is still missing.
- Ask who will advise you if the delivery does not arrive in time, and how to reach them outside normal hours.
- Keep the old pharmacy’s cancellation and dispatch dates clear, so you do not end up with two orders by mistake.
- If you miss a dose, write down the date. Then follow the product advice or the clinical plan for your situation.
A dispatch promise is no prescribing decision. A comparison site cannot approve a restart or fix a clinical delay. Use our delivery planning guide and duplicate-order checklist alongside the clinical advice.
Spacing out injections to make a pack last longer
Do not make your own gap to stretch a pack. Spacing out injections on purpose changes your dosing, so talk to your prescriber first. A missed-dose rule does not approve an ongoing schedule. If price is the problem, ask about an affordable treatment plan and compare suitable pharmacies.
Compare the same prescribed medicine through our comparison guides for each treatment. Allow time for the consultation and delivery. A discount should never set your next dose date.
Message template for your clinical team about a missed dose
I take [brand, form and strength]. My last dose was on [date and time, if known]. My next dose was due on [date]. I missed [details] because [reason]. My symptoms now are [details or none]. Changes to my medicines or health: [details]. My last prescription and delivery dates were [dates]. Please confirm whether I can follow the single missed-dose rules or need a restart review. Please send my next dose and timing in writing.
Mark any date you are unsure of. Do not upload health records to a comparison site, or send them to someone sharing a discount code.
GLP-1 side effects that need urgent medical help
Get urgent medical help for severe stomach pain which does not go away, especially if the pain spreads to your back or comes with vomiting. Ongoing vomiting or diarrhoea can cause serious dehydration. MHRA guidance explains these risks. Tell the clinician which medicine you used and when. A late delivery or a cheaper quote never comes before a serious symptom.
Frequently asked questions
What if I miss a Mounjaro injection by more than four days?
Skip the missed Mounjaro dose and take the next one on your usual day, says the UK leaflet. If you are four days late or less, take the missed dose as soon as you remember. Leave at least three days between doses.
How late can I take a missed Wegovy injection?
Take a missed Wegovy injection as soon as you remember if five days or less have passed since the due date, says the UK leaflet. After more than five days, skip the dose and take the next one on your usual day. Never take a double dose.
Do I need a restart review after missing several GLP-1 doses?
Yes. Contact your prescriber before restarting after two or more missed doses or a longer break. Wegovy prescribing information says a lower starting dose should be considered. NICE asks clinicians to look at why tirzepatide treatment stopped.
What should I do if I miss a Wegovy tablet?
Leave out the forgotten Wegovy tablet and take the next one the following day, says the UK tablet prescribing information. The four-day Mounjaro and five-day Wegovy injection windows do not apply to daily tablets.
Does my pharmacy’s gap calculation match my last injection date?
Not always. MedExpress, for example, counts a gap from the previous prescription date to the new order date. When you switch pharmacy, give the date of your last injection as well as your prescription and delivery dates. Each date is a separate fact.
Sources
Links checked on 6 October 2026. Provider prices and policies change, so confirm the details with the provider before you pay. The organisations linked here have not reviewed or endorsed this guide.
- Lilly: Mounjaro KwikPen patient information leaflet, via emc
- Novo Nordisk: UK Wegovy FlexTouch patient leaflet
- Novo Nordisk: UK Wegovy FlexTouch prescribing information, section 4.2
- Novo Nordisk: UK Wegovy tablets prescribing information
- NICE: guide to prescribing medicines for overweight and obesity, including restarting tirzepatide
- MedExpress: managing a gap in Mounjaro or Wegovy treatment
- MHRA: GLP-1 medicine risks and when to seek medical help
Pharmacy Hopper does not give medical advice. Read our editorial standards.