Mounjaro is taken once a week, so it can be easy to forget taking your injection occasionally.
If you've missed your usual injection day, don't panic.
What you should do depends on how long it has been since your missed scheduled dose.
The Mounjaro dosing instructions are quite specific, so it's important not to take two doses within a narrow time-frame close together.
Here's what you need to know:
I forgot to take my Mounjaro dose. What should I do?
The current Mounjaro product information gives a simple rule:
If it has been 4 days or less
Take the missed dose as soon as possible.
You can then return to your normal weekly injection schedule.
If it has been more than 4 days
Skip the missed dose.
Take your next dose on your regularly scheduled day.
Do not take two doses to make up for the missed injection.
Can I take Mounjaro late?
Yes.
If your usual injection day has passed but it has been no more than 4 days, the missed dose can be taken as soon as possible.
For example, if you normally take Mounjaro on Monday but remembered it on Wednesday, you can take the missed dose when you remembered it on Wednesday.
You can then return to your usual schedule taking your injection on Monday.
If more than 4 days have passed, say you remembered your missed dose on Saturday, skip the missed dose. You can then take the next dose on Monday as scheduled.
Can I change my Mounjaro injection day?
Yes, if necessary.
The Mounjaro patient information leaflet allows you to change your weekly injection day, provided at least 3 days (72 hours) have passed since your last actual injection.
For example, if you took your last dose at 8pm on Monday, Thursday at 8pm would be 72 hours later. Thursday morning would be too soon. Count the hours from the injection you actually took, rather than just counting the calendar days.
Once you've changed your injection day, you can continue taking Mounjaro once a week on the new chosen day (Thursday).
Important Note:
Don’t change your injection day in a way that results in the two doses being taken less than 3 days apart.
What if I accidentally take two doses too close together?
Don't take another Mounjaro dose until you've received appropriate advice.
Taking more than prescribed can cause low blood sugar (hypoglycaemia), nausea and vomiting, as described in the patient information leaflet. The prescribing information (Summary of Product Characteristics) states that there is no specific antidote for an overdose of tirzepatide; healthcare professionals provide supportive treatment according to the person's symptoms and may need to monitor them for a prolonged period.
If you've accidentally taken more Mounjaro than prescribed, contact your doctor immediately for advice. Do not wait for symptoms to appear.
If you're experiencing severe symptoms, seek urgent medical attention.
What if I've missed more than one Mounjaro dose?
The standard missed-dose instructions cover a single missed dose.
If you've missed multiple doses, don't simply assume that you should restart at your previous dose.
Speak to your prescriber before restarting treatment, particularly if you've been without Mounjaro for an extended period.
Your previous dose, how long you've been without treatment, and your individual circumstances may all be relevant.
Will missing a Mounjaro dose affect my weight loss?
Missing one dose does not mean that your treatment has failed.
However, taking Mounjaro consistently as prescribed is important because the medicine is designed to be taken once weekly.
If you've missed a dose, follow the instructions above rather than trying to compensate by taking an extra injection.
If you are regularly forgetting doses, consider setting a weekly reminder on your phone or choosing a consistent day that fits easily into your routine.
What if I miss my dose because I'm feeling unwell?
If you've missed your injection because you're experiencing side-effects, don't automatically take the missed dose without considering how you're feeling.
Nausea, vomiting and diarrhoea are common side-effects of Mounjaro, particularly during dose escalation. They generally become less promenent over time.
If you're experiencing significant or persistent side-effects, speak to your prescriber.
NICE advises that Mounjaro doses should not be increased during the titration stage if an adverse effect has not resolved or has not become tolerable.
For more information, see: Mounjaro Side Effects: What to Expect and When to Get Help
What if I miss my dose while travelling?
Travelling doesn't change the missed-dose rules.
If you have your Mounjaro with you and are within 4 days of your scheduled dose, follow the usual instructions.
If more than 4 days have passed, skip the missed dose and take your next injection on your normal day.
You should also make sure that Mounjaro is stored correctly while travelling. Follow the storage instructions provided with your medicine and check the Patient Information Leaflet for specific requirements.
The main thing to remember
If you forget your Mounjaro injection, the most important thing is not to take doses too close together.
Remember:
- 4 days or less: take the missed dose as soon as possible.
- More than 4 days: skip the missed dose and take your next dose on the usual day.
- Never take two doses within 3 days of each other.
If you've missed multiple doses or you're unsure what to do, speak to your prescriber or pharmacist.
Frequently asked questions
How many days can I be late taking Mounjaro?
You can take a missed dose within 4 days (96 hours) of the scheduled time. If more than 4 days have passed, skip the dose.
Should I take two Mounjaro injections if I miss one?
No. Do not take a double dose or an extra injection to make up for a missed dose. Always leave at least 3 days (72 hours) between any two doses.
What happens if I miss taking Mounjaro for a week?
If more than 4 days have passed since your scheduled dose, skip the missed dose and take your next dose on your normal day.
Can I change the day I inject Mounjaro?
Yes. The day can be changed provided there are at least 3 days between the doses.
What happens if I miss several Mounjaro doses?
Speak to your prescriber before restarting, particularly if you've been without treatment for an extended period. Don't assume that you should automatically restart at your previous dose.
Can I take Mounjaro early?
If you're changing your injection day, there must be at least 3 days between the two doses. Do not take doses closer together than this time frame.
Related articles
You may also find these useful:
- Mounjaro Side Effects: What to Expect and When to Get Help
- How Long Should You Take Mounjaro for Weight Loss?
- Who Can Get Mounjaro for Weight Loss?
- What Can You Eat While Taking Mounjaro?
- How Does Mounjaro Work?
Considering Mounjaro?
If you're considering prescription weight management treatment, Genmeds offers an online consultation where a prescriber can assess whether treatment is appropriate for you.
If prescribed, Mounjaro should be used alongside a reduced-calorie diet and increased physical activity.
