How should I store my Mounjaro or Wegovy pen?

Guides

Written By Eesa Shaikh - updated 16/03/2026 14:00Reviewed By Wajahet Ali Bhatti - 16/03/2026 11:00

Proper storage of your medication is essential in ensuring it remains safe and effective. As Mounjaro and Wegovy are temperature sensitive, they must be stored correctly from the moment you receive them.

Storage comparison

	Mounjaro	Wegovy
Unopened Storage	Fridge (2℃ to 8℃)	Fridge (2℃ to 8℃)
Once in use	Up to 30 days	Up to 6 weeks
In-use temperature	Below 30℃, but ideally in a Fridge	Below 30℃, but ideally in a Fridge
If Frozen	Do Not Use	Do Not Use
Light protection	Keep cap on when not in use	Keep cap on when not in use

Specific Guidelines

Mounjaro (Tirzepatide)

The Fridge rule - Store the Mounjaro KwikPen in the refrigerator (2℃ to 8℃). Make sure it does not touch the back or sides of the fridge and keep away from the freezer compartment.
The 30-day clock - Once you have opened the pen for the first time, it can be kept at room temperature (below 30℃) for a maximum of 30 days. After 30 days, any remaining liquid left in the pen must be discarded.

Wegovy (Semaglutide)

The Fridge rule - Store the Wegovy Pen in the refrigerator (2℃ to 8℃). Make sure it does not touch the back or sides of the fridge and keep away from the freezer compartment.
The 6-week clock - Once you have opened the pen for the first time, it can be kept at room temperature (below 30℃) for up to 6 weeks. After this time, any remaining liquid left in the pen must be discarded.

Important safety Checks

Before each dose, visually inspect the medication. Do not use if:
- The liquid is cloudy, discoloured or you can see particles. (the solution should be clear and colourless)
- The pen has been accidentally frozen. (freezing destroys the chemical structure of the drug)
- The pen appears damaged.

Tips for Maintenance

To make sure the pen lasts the duration of treatment, and doesn’t jam, follow these tips:

Protect the mechanism - do not store the pen upright on the dose knob as this can damage the internal mechanism. Store the pen on its side, with the cap on.
Keep it clean - avoid storing your pen in areas likely to hold debris like the bottom of a handbag or rucksack. Small dust particles can enter the mechanism causing it to jam
Temperature fluctuations- if the medication has been left out of the fridge for a long time, or exposed to extreme high or low temperatures, do not use it.