Semaglutide Left Out of the Fridge: What the Guidance Actually Says

What the SmPC actually specifies about room-temperature storage

The starting point is the prescribing information, not forum advice. The Wegovy SmPC, published on the Electronic Medicines Compendium, states that each pen (opened or still sealed) may be kept at temperatures up to 30°C for a maximum of 28 consecutive days. After that point it must be discarded, even if some solution remains. This is a cumulative limit: days spent on the kitchen counter in January and days left on a warm shelf in July all count toward the same 28-day total for that pen.

The fridge target is 2–8°C. Pens stored there (away from the freezer compartment and not touching the back wall, where ice can form) are stable until the expiry date printed on the label. Once a pen has been out at room temperature, returning it to the fridge does not reset the clock, the 28 days started the moment it left cold storage and keeps ticking whether the pen is in the fridge or not. Our dedicated page on semaglutide out of the fridge explains exactly how to track that running total and what counts as the starting point.

For a fuller picture of how semaglutide storage interacts with your treatment plan, the guide to semaglutide fridge storage covers every scenario in detail, including what to do at weekends and during power cuts.

Frozen, overheated, or out for longer than 28 days: the discard cases

Three situations require discarding the pen without injecting it. First: freezing. If a pen has been stored against the back wall of the fridge and frozen, or left in a car boot on a cold night, the solution may have been damaged even if it looks normal. Semaglutide can degrade on freezing without any visible change to the liquid. Second: sustained heat above 30°C. A pen left in a hot car, on a windowsill in direct sunlight, or near a radiator may have been exposed to temperatures well above the 30°C ceiling, and again visible appearance is not a reliable guide. Third: the 28-day limit has passed. There is no grace period and no visual cue, the pen looks identical whether it is on day 27 or day 35.

In all three cases, the right step is to discard the pen in a sharps container rather than the household bin, and to contact your prescriber promptly. Missing a weekly dose is inconvenient; injecting a degraded medicine is a different kind of risk. Your prescriber can advise whether to inject on schedule with a replacement pen or to wait until the next planned dose day, that decision belongs with them, not with a storage table.

If you are trying to work out exactly how long your pen has been out, our page on how long semaglutide can safely be out of the fridge works through the timing in plain terms.

Unopened pens left out: a slightly different picture

The 28-day room-temperature rule applies equally to pens that have never been activated. An unopened Wegovy pen left on the worktop overnight is fine, provided the temperature stayed below 30°C and the total time out of cold storage does not exceed 28 days. Many people accidentally leave a delivery bag by the front door on a mild afternoon and worry unnecessarily, if it has been a few hours and the room was not unusually warm, the pen is almost certainly unaffected. The specific guidance for unopened semaglutide pens works through these scenarios more carefully.

Spare pens you are not yet using are better kept in the fridge until needed, simply because there is no benefit to shortening their room-temperature window before the current pen is finished. A practical habit: keep the active pen in the fridge door and bring it to room temperature for a few minutes before each injection, which tends to reduce stinging at the injection site. The pen does not need to be cold when you inject, it just needs to have stayed within the permitted storage conditions.

Cost and access questions come up alongside storage ones fairly often. If you are managing a prescription through a private pharmacy and want to understand how pricing and coverage work, our overview of getting Wegovy online explains what is included in a legitimate private prescription service.

When to contact your prescriber, and what to tell them

Storage mishaps are more common than people think, and prescribers hear about them regularly. The NHS guidance on weight-management injections, published by NHS England, consistently reinforces that clinical support (not self-management alone) is central to safe use of these medicines. If you are unsure whether to inject a pen that has been left out, or you need to discuss replacing a pen and how that affects your dose timing, contact your prescriber before injecting. Do not delay your next dose unnecessarily, but equally do not inject from a pen you have reasonable grounds to doubt.

When you call or message, it helps to have three pieces of information ready: the approximate time the pen was out, the likely temperature of the space it was in (a warm kitchen versus a hot car makes a real difference), and how much solution remains in the pen. That gives the prescriber enough to advise you clearly. Some people find it useful to note the date they first take a pen out of the fridge, a sticky label on the pen itself, changed at each injection day, takes about five seconds and avoids a lot of uncertainty. That kind of small habit is something our prescribers often mention to patients who are starting out on Wegovy.

If you are new to Wegovy or are considering starting semaglutide for weight management, the free consultation at nume connects you with a GPhC-registered Independent Prescriber who can assess your suitability and talk through the practical side of treatment, including storage, on the same day. Check your eligibility and get started there.