Counterfeit weight-loss pens in Spain: how to stay safe
Medically Reviewed by Dr. Pedro Yelamo Vera, MD
Licensed Physician No. 484814280 · Official Medical College of Bizkaia (Spain)Last reviewed: 12 October 2026
Counterfeit weight loss pens are sold online and on social media. Learn the rules in Spain, the red flags, and what to do if you used a suspect product.
You don't have to figure this out alone
Dr. Pedro Yelamo Vera is an independent, bilingual GP licensed in Spain. Book a 15-minute video consultation in English or Spanish for €50, with a private electronic prescription issued under Spanish law when clinically appropriate.
Weight-loss injections are in high demand. Where there is demand, fake products follow. Counterfeit weight loss pens have been found in Europe, and illegal sellers advertise them online every day. This guide explains the rules in Spain, how to spot a risky seller, and what to do if you are worried about a pen you used.
- GLP-1 weight medicines are prescription-only. In Spain they are supplied only by a pharmacy, against a prescription.
- Prescription medicines cannot be sold online in Spain. Pens sold on social media, in gyms or "no prescription needed" are illegal.
- EU, WHO and Spanish regulators have all warned about fake GLP-1 products.
- A fake pen may contain the wrong dose, no medicine, or something harmful such as insulin.
- If you used a suspect pen: stop, keep it, see a doctor, and report it.
What the regulators have said
This is not a rumour. Several health bodies have issued formal warnings.
- European Medicines Agency (EMA), October 2023. Fake pens labelled as a semaglutide product (Ozempic) were found at wholesalers in Austria and Germany. They used batch and serial numbers copied from real packs. The EMA said none were known to have reached patients through legal pharmacies.
- World Health Organization (WHO), June 2024. WHO issued a formal alert on fake semaglutide batches found in Brazil, the UK and the US. It said reports of fake products had been rising in all regions since 2022. It warned that some may contain no active drug, and others may contain other drugs such as insulin.
- EMA, Heads of Medicines Agencies and AEMPS, September 2025. Europe's medicine regulators, including Spain's AEMPS, warned of a sharp rise in illegal products sold as GLP-1 medicines. They named fake websites, fake Facebook profiles and adverts. Some misuse official logos or claim false approval.
Why a fake pen is a real risk
A fake product is not just a waste of money. It can harm you in several ways.
- No medicine at all. Your blood sugar or weight may stay out of control. This matters most if you have diabetes.
- The wrong amount. Too much can cause severe sickness and dehydration.
- A different drug. Insulin hidden in a pen can cause dangerously low blood sugar.
- Not sterile. An injection made outside proper controls can cause infection.
- No medical check. Without a doctor, nobody checks whether the medicine is safe for you, or whether it clashes with your other medicines.
The rules in Spain
GLP-1 medicines such as semaglutide (Wegovy, Ozempic), tirzepatide (Mounjaro) and liraglutide (Saxenda) need a prescription. A pharmacy hands them over when you show a valid prescription.
Spain's rules on online sales are strict. Royal Decree 870/2013 lets pharmacies sell non-prescription medicines online, and nothing else. AEMPS states that prescription medicines, GLP-1 medicines included, cannot be sold over the internet in Spain.
So any offer to post you a weight-loss pen without a pharmacy visit is outside the law. That includes sellers on Instagram, TikTok, WhatsApp, Telegram or marketplaces. It also includes a "friend of a friend" at the gym or beauty salon.
What about the EU online pharmacy logo?
Legal online pharmacies in the EU show a common logo. When you click it, it should take you to the pharmacy's entry in an official national register. In Spain, that register is AEMPS's Distafarma list. A site without the logo, or not on the register, should be treated as fake.
But remember: in Spain, even a legal online pharmacy can only sell non-prescription medicines online. The logo does not make an online offer of a weight-loss pen legal here.
Compounded copies and "research peptides"
Some sites sell vials of powder or liquid labelled "for research only" or "not for human use". Others sell "compounded" copies. These are not authorised medicines. Nobody has checked their quality, strength or purity. The US FDA has warned firms that sell such products to the public, often with dosing tips. It has also had reports of people needing hospital care after dosing errors with unapproved copies.
How to check your pen
The safest step is where you get it. A pen supplied by a Spanish pharmacy, against a prescription, comes through a checked supply chain.
Since February 2019, prescription medicine packs in the EU carry two safety features:
- a unique identifier, a 2D barcode with a serial number for that pack, and
- an anti-tampering seal that shows if the box has been opened.
The pharmacy scans the code when it hands over the pack. This checks that the pack is genuine. You cannot do this check yourself with an app. But you can look for warning signs:
- The box seal is broken, or the box looks opened and re-closed.
- The label is in a language that does not match the place you got it, with no Spanish leaflet.
- Spelling errors, poor print or colours that differ from a previous pack.
- No patient leaflet, or a leaflet that does not match the pen.
- The liquid is cloudy or has a colour. The patient leaflet for genuine pens says the solution should be clear and colourless.
- The pen arrived unrefrigerated by post. Genuine unopened pens must be kept in the fridge.
Compare your pen with the pictures and description in the official patient leaflet. You can find it on CIMA, the AEMPS medicines database. If anything looks wrong, do not use it. Take it to a pharmacist.
Red flags when buying
| Red flag | Why it matters |
|---|---|
| "No prescription needed" | Illegal for these medicines in Spain |
| Sold by DM, social media, gyms or salons | Not a pharmacy; no safe supply chain |
| Price far below a pharmacy | Often a sign of a fake or stolen product |
| Claims of approval by a health body | Regulators do not endorse brands or sellers |
| "Better than" real medicines, or "research only" | No evidence, no quality control |
| Payment by crypto, bank transfer to a person, or vouchers | Hard to trace; common in scams |
What to do if you used a suspect product
- Stop using it. Do not inject any more from that pen or vial.
- Keep it. Keep the pen, the box, the leaflet and any messages or receipts. Do not throw them away.
- See a doctor. Tell them what you used and when. If you have diabetes, check your blood sugar more often.
- Report it. Tell a pharmacist and report the product or website to AEMPS. You can also report any side effect at notificaRAM.es, the AEMPS form for the public.
Get urgent help if you notice:
- Shaking, sweating, confusion, fainting or a fit (possible low blood sugar).
- Severe tummy pain that does not go away, or that spreads to your back.
- Vomiting that will not stop, or signs of dehydration.
- Swelling of the face or throat, a spreading rash, or trouble breathing.
- Redness, heat, pus or fever around the injection site.
For a medical emergency, call 112 or go to the nearest local emergency department. Do not wait for a video consultation or an online reply.
If you are pregnant or could be pregnant, do not use these products. GLP-1 weight medicines are not used in pregnancy or while breastfeeding. Under-18s need care led by a specialist team. If you have ever had an eating disorder, talk to a doctor before any weight treatment.
Talk to a GP, not a seller
A video visit from anywhere in Spain to review your weight and health safely.
The safe route
If you are thinking about weight medicine, start with a doctor. A proper review looks at your health, your other medicines and your goals. It may also include blood tests. Medicine is one option, not the only one.
The Weight Optimization consultation is a 30-minute medical review of weight and metabolic health by video. Where clinically appropriate, following a genuine evaluation. Treatment and prescriptions are issued solely at the doctor's discretion based on evidence-based clinical guidelines. If medicine is right for you, you get a private electronic prescription under Spanish law. You then collect it from the pharmacy of your choice.
Dr. Pedro Yelamo Vera is a GP licensed in Spain (Colegiado No. 484814280).
Frequently asked questions
Can I buy weight-loss injections online in Spain?
No. Prescription medicines cannot be sold online in Spain. You need a prescription, and you collect the medicine from a pharmacy.
Is it safe to buy a pen from someone at my gym or on Instagram?
No. These sellers are outside the law and the supply chain is not checked. The pen may be fake, the wrong strength or not stored safely.
How can I tell if my pen is fake?
Check the seal, the label, the leaflet and the liquid, and compare it with the official leaflet on CIMA. A Spanish pharmacy scans each pack's unique code to confirm it is genuine. If in doubt, do not use it.
Are 'research peptide' vials the same medicine?
No. Products labelled 'research only' or 'not for human use' are not authorised medicines. Their content and purity are unknown.
What should I do if I injected a suspect product?
Stop, keep the product and packaging, see a doctor, and report it to AEMPS. For severe symptoms, call 112.
Does the EU online pharmacy logo mean an offer is legal?
Not for prescription medicines in Spain. The logo shows a registered pharmacy, but Spanish pharmacies may only sell non-prescription medicines online.
Sources
- AEMPS: EMA and HMA warn of a rise in illegal medicines sold as GLP-1 analogues (3 September 2025)
- EMA: Warning about sharp rise in illegal medicines sold in the EU (2025)
- EMA: Alert on falsified pens (18 October 2023)
- WHO: Warning on falsified medicines used for diabetes and weight loss (20 June 2024)
- BOE: Real Decreto 870/2013 on online sale of non-prescription medicines
- AEMPS: Questions and answers on medicine safety features
- AEMPS: Online reporting of suspected side effects by the public (notificaRAM)
- US FDA: Concerns with unapproved GLP-1 drugs used for weight loss
Related guides
Medical Citations & Sources
This content is written and reviewed by a licensed physician with reference to the following official health authorities.
