Medication errors have occurred with injectable forms of GLP-1 analogues and dual GIP/GLP-1 analogues. Below are a few reminders for a proper use of these medicines.
The Federal Agency for Medicines and Health Products (FAMHP) has been informed that medication errors have occurred in large numbers with injectable presentations of analogues of the incretin hormone glucagon-like peptide-1 (GLP-1) and dual GIP/GLP-1 analogues.
The errors often consist of overdosing and expose patients to an increased risk of side effects (and their intensity), such as hypoglycaemia (which can include palpitations, tremors, agitation, confusion, etc.), headaches, gastrointestinal disorders that can lead to dehydration (nausea, diarrhoea, vomiting, constipation).
Based on the reports received, the main causes of these errors include:
- incorrect use of the injection pen;
- failure to comply with the prescribed dosage.
Misuse of the product for ‘aesthetic’ purposes could also be a factor that can contribute to errors.
Which medicines are affected?
Dulaglutide, liraglutide and semaglutide are analogues of the incretin hormone glucagon-like peptide-1 (GLP-1). GLP-1 is an intestinal hormone that controls blood sugar levels by slowing gastric emptying, reducing glucagon release in pancreatic α-cells and stimulating glucose-dependent insulin secretion in β-cells (Commented Directory of Medicines, CBIP/BCFI - GLP-1 analogues).
Tirzepatide is a ‘dual agonist’ of both GLP-1 and glucose-dependent insulinotropic polypeptide (GIP). It increases food-stimulated insulin secretion and insulin sensitivity. It also reduces glucagon secretion and food intake, and delays gastric emptying (Commented Directory of Medicines, CBIP/BCFI - dual GIP/GLP-1 analogues).
The indications for the various specialities containing a GLP-1 analogue or a dual GIP/GLP-1 analogue are summarised in the table below.
| Indications |
Dulaglutide |
Liraglutide |
Semaglutide |
Tirzepatide |
| Treatment of type 2 diabetes (in combination with other antidiabetics or as monotherapy when metformin is not tolerated or contraindicated)* | Trulicity | Victoza |
Ozempic, Rybelsus |
Mounjaro |
| Weight control* | Saxenda | Wegovy | Mounjaro |
*Situation as of 7 November 2025, summary of the indication. For the full indication, please refer to the summary of product characteristics (SPC), available on the FAMHP website.
With the exception of Rybelsus, which comes in tablet form, all the specialities listed above must be injected subcutaneously.
These medicines are only available in pharmacies and require a medical prescription. Their online sale is therefore banned in Belgium.
Advice for healthcare professionals
- Provide patients and healthcare professionals with full and clear instructions on dosage.
- Explain to patients and healthcare staff how to use the injection pen correctly.
Inform patients of the symptoms of overdose.
Advice for patients
The FAMHP calls for greater vigilance in using these medicines.
- Only use these medicines on medical advice and only if they are intended for you.
- Follow the prescribed dose: a higher dose will not speed up weight loss but will increase the risk of potentially serious side effects.
- Do not buy these medicines on the internet and, as with any medicine, buy them from legal pharmacies and under the supervision of a pharmacist.
- Read the instructions for use in the package leaflet carefully to ensure correct use of the injection pen. If in doubt, ask your doctor or pharmacist for advice.
- Remain alert for any side effects. If you experience any, contact your doctor or pharmacist.
Always report a side effect
The FAMHP reminds you of the importance and necessity of reporting any potential or actual medication errors which have led to side effects or not.
Report medication errors to the FAMHP.
- Without side effect: medication-errors@fagg-afmps.be
- With side effect: use the standard reporting system to describe the circumstances of the error at www.famhp.be/en/side_effect/ or via a notification form available on the FAMHP website.
If you have any urgent questions relating to necessary measures in the event of a medication error, please call the Belgian Poison Control Centre (Centre Antipoisons/ Antigifcentrum) (+ 32 70 245 245).
More information
- Consolidation of reimbursement conditions for Ozempic and other GLP-1 analogues (NIHDI) in order to help fight the significant misuse of their reimbursement outside the indication of diabetes.
- Illegal sale of weight-loss medicines on social media
- How to use GLP-1 medicines correctly for weight loss?