What to do depends on how far away your next scheduled dose is, and the rule differs between products. Check the instructions for your specific medication, or call your pharmacist, who can answer this in under a minute. What you should not do is take two doses close together to catch up.
Never double up. Taking a missed dose too close to the next scheduled one means a much larger amount in your system at once, and the gut effects can be severe. If you are unsure whether you are inside the window, skip it and take the next one on schedule rather than guessing.
For how this fits into the wider titration picture, see GLP-1 Dosing and Titration: The Complete Guide.
The logic behind the rule
These are weekly medications with a long duration of action. Missing one does not undo your progress, and there is a window in which taking it late is fine.
The question is only whether taking it now would put it too close to your next scheduled dose. Beyond a certain point, the correct move is to skip and resume normally.
Each product states that threshold precisely in its instructions for use, which is why a general article should send you to the specific one rather than offer a number that may not apply to what you take.
Where to find the answer in two minutes
The instructions for use that came with your pen state it directly. If you have discarded them, your pharmacist can tell you immediately, and a pharmacy call is faster than waiting for a prescriber callback.
Many manufacturers also publish the guidance on the product website.
Longer gaps
Missing several weeks is a different situation from missing one. After an extended break, your tolerance may have fallen, and restarting at the dose you were on can produce the symptoms you had when you first reached it.
Products give guidance on how long a gap warrants re-initiating at a lower dose. This is a prescriber conversation rather than something to judge yourself, and it is worth having before you inject rather than after.
Keep your injection day consistent
Missed doses usually come from a drifting schedule rather than a single forgetting. A fixed day, an alarm, and keeping the pen somewhere you will see it prevent most of them.
If your day has drifted, changing it deliberately is straightforward but should be done with your prescriber’s input rather than by shifting it on your own.
If you missed it because you could not get a refill
A supply or coverage gap is a different problem, and it is worth telling your prescriber the reason for the interruption rather than only the fact of it. Interruptions caused by shortages or authorization lapses sometimes change what happens next, including whether re-titration is needed.
Never double up to catch up. After a longer gap tolerance falls, which is covered in restarting after a break. Missed doses usually come from a drifting schedule rather than one lapse, and fixing your injection day prevents most of them.
Frequently asked questions
Will one missed dose set me back?
Unlikely to matter much. These medications persist in the body for days, and a single miss is a common occurrence.
Can I take it a day late?
Usually yes, within the window your product specifies. Check the instructions for use.
What if I already doubled up?
Contact your prescriber or pharmacist for advice, and seek urgent care if you develop severe abdominal pain or persistent vomiting.
Do I restart the titration schedule?
For a short gap, generally not. After a longer break, possibly. Ask rather than assume.
Can I change my injection day permanently?
Usually straightforward, but arrange it with your prescriber rather than shifting it yourself.
What if I am unsure how long it has been?
Skip and resume on your normal schedule, and ask your pharmacist. Skipping is the safer error.