What should you do if you lose your Wegovy pen?

If a pen is lost, do not try to replace it with another GLP-1 medicine unless advised by a clinician. Contact your NHS clinic or pharmacy to discuss a replacement and how to manage any missed doses. Following the five-day rule for missed injections will guide whether to take the next dose early or wait. Keeping pens stored securely and bringing only what you need when travelling reduces the chance of loss.

Why replacement must be clinician-led

Wegovy contains semaglutide, a specific GLP-1 receptor agonist licensed in the UK for weight management under NICE TA875. If a pen is lost, patients may be tempted to substitute it with another GLP-1, such as liraglutide (Saxenda), dulaglutide (Trulicity), or tirzepatide (Mounjaro). However, these medicines have different dosing schedules, strengths, and approved uses. NICE guidance makes it clear that substitution should only be managed by a prescriber within a structured programme. The STEP and SELECT trials were based on once-weekly semaglutide 2.4 mg, and other GLP-1s have not been tested in the same way for weight loss. Attempting to self-switch could lead to underdosing, overdosing, or unnecessary side effects. For this reason, the safest option is to contact the NHS clinic or pharmacist who issued the prescription and let them decide the next steps.

Managing missed doses

If a lost pen means an injection is missed, there is clear NHS advice. The “five-day rule” is straightforward: if you remember within five days of the scheduled dose, you can inject as soon as possible. If more than five days have passed, skip that dose and take the next one at your usual time. Doubling up is never recommended, as it increases the risk of side effects without improving results. This guidance reflects the stability of semaglutide in the body, as shown in clinical trials. STEP-5, which followed participants for two years, demonstrated that small variations in timing did not undermine outcomes, provided the overall weekly pattern was maintained. NHS services emphasise that a single missed dose is unlikely to cause harm, but repeated gaps can reduce effectiveness.

Practical steps if a pen goes missing

Losing a pen at home or while travelling can be stressful, but there are practical ways to handle the situation. First, check whether you have a spare pen stored safely. Some clinics issue more than one pen at a time, particularly during stable maintenance phases. If not, contact your pharmacy or clinic as soon as possible to arrange a replacement. NHS commissioning guidance recognises that supply constraints have been an issue with GLP-1 medicines, so replacement may require some coordination. Patients are advised not to borrow medicines from friends or family, even if they are prescribed similar drugs, as this is unsafe. In the meantime, following the five-day rule will help decide whether to inject later or wait until the next scheduled dose.

Preventing loss in the first place

Prevention is the best strategy, and NHS staff often provide tips to avoid losing pens. At home, keeping pens in a consistent storage place such as the fridge door or a dedicated medicine box reduces the chance of misplacing them. When travelling, it is best to carry only the pens you need for the trip, rather than transporting an entire supply. Some patients have found it helpful to store pens in a labelled case with a sharps bin included, keeping everything together. Others keep a small notebook or app-based log to track how many pens they have left. Clinics also advise against leaving pens loose in luggage or handbags, where they can be lost or damaged. These practical habits make it less likely that a pen will be misplaced.

Support from the NHS and manufacturer

NHS clinics and pharmacies are the first points of contact if a pen is lost. They can advise on whether a replacement is immediately available and how to manage dosing until then. In some areas, specialist weight management services offer helplines for patients using GLP-1s, providing quick advice. The manufacturer, Novo Nordisk, also provides patient support materials and contact centres. While they do not supply replacements directly, they can give information on safe storage, handling, and disposal, which may help reduce future risks. NICE TA875 emphasises that semaglutide should always be prescribed with structured follow-up, and this includes guidance on handling unexpected situations like lost pens. Patients are encouraged to use these services rather than making decisions alone.

The bigger picture

Losing a Wegovy pen is inconvenient, but it does not have to disrupt treatment long term. The key steps are to avoid self-replacement, contact NHS services promptly, and follow the five-day rule for missed doses. Preventive measures such as secure storage and careful travel planning further reduce risks. NICE guidance, NHS support pathways, and trial evidence all reinforce the same message: safety and consistency depend on clinician-led management and good patient habits. The bigger picture is that while individual pens can be misplaced, treatment goals remain achievable with the right support and preparation.