How to report a side effect through the Yellow Card scheme

Section 4 of the Wegovy and Mounjaro leaflets ends with the same request: if you get any side effects, talk to your doctor, pharmacist or nurse, and you can also report them directly through the Yellow Card scheme. The Wegovy leaflet gives the address yellowcard.mhra.gov.uk. The Mounjaro leaflet gives the MHRA's address and adds that you can search for "MHRA Yellow Card" in the Google Play or Apple App Store. This article explains what the scheme is and how a report works.

What the scheme is

The Yellow Card scheme is run by the Medicines and Healthcare products Regulatory Agency (MHRA). The MHRA's guidance calls it "vital in helping the Medicines and Healthcare products Regulatory Agency (MHRA) monitor the safety of all healthcare products in the UK". Reports from patients and professionals are how the regulator picks up problems that did not show in trials, which involve a limited number of people for a limited time.

The scheme covers more than side effects. The Yellow Card website says: "Anyone can report an issue with a medicine, vaccine, medical device (including software, apps and artificial intelligence), blood product or e-cigarette to the Yellow Card scheme." The MHRA's guidance lists suspected adverse reactions to medicines, vaccines, herbal remedies and homeopathic products, incidents with medical devices, defective medicines and counterfeit products. A pen bought from a seller you later suspect was not a pharmacy is as much a Yellow Card matter as a symptom.

You do not have to be certain

The MHRA's guidance is explicit: "You do not have to prove causality to report a suspected ADR, only a suspicion is needed." A report records a suspicion that a product and a symptom might be connected. The MHRA's staff and systems do the work of deciding whether the pattern across many reports means anything.

Both leaflets ask you to report side effects "not listed in this leaflet" as well as the listed ones, because an unlisted effect is the kind the scheme exists to find.

Wegovy and Mounjaro both carry an inverted black triangle with the words "This medicine is subject to additional monitoring." The MHRA explains that the triangle marks products "under additional monitoring" and that "It does not mean the medicine is unsafe." It asks for all suspected reactions to these products to be reported, including the ones already listed in the leaflet, so that the regulator builds the fullest picture of a newer medicine.

Three ways to report

• Online at yellowcard.mhra.gov.uk. The site accepts reports without an account.
• Through the free Yellow Card app, available from the Apple App Store and Google Play.
• By phone on 0800 731 6789, free, Monday to Friday between 9am and 5pm, which the MHRA offers for people without online access.

Your pharmacist, prescriber or nurse can also file a report on your behalf, and healthcare professionals have their own routes through clinical IT systems. A report describes the suspected side effect and names the medicine you suspect. The symptom log in The Dose Club app, which records each symptom with a severity, a note and the day since your last dose, is a record of the dates and the pattern to have beside you when you fill the form in, as is the box the pen came in. The app never files a report for you and never decides whether a symptom is a side effect; that judgement is yours and your prescriber's.

What happens to a report

The MHRA reviews reports and, in its words, acts "if necessary" to "minimise risk and maximise benefit to patients and the public". The regulator gives no individual medical advice through the scheme, and the Yellow Card website directs health concerns to NHS 111 or a healthcare professional. A Yellow Card is a report to the regulator. For a symptom that worries you now, section 4 of the leaflet says which effects need urgent help, and your prescriber or NHS 111 are the people to call; the side effects article on this site quotes the relevant passages.

Sources

• MHRA, The Yellow Card scheme: guidance for healthcare professionals, patients and the public: gov.uk
• Yellow Card website, MHRA: yellowcard.mhra.gov.uk
• Wegovy FlexTouch patient information leaflet, section 4, electronic medicines compendium: medicines.org.uk/emc/product/13800/pil
• Mounjaro KwikPen patient information leaflet, section 4, electronic medicines compendium: medicines.org.uk/emc/product/15481/pil
• The Dose Club, Common side effects and when the leaflets say to seek help (article on this site)

This article is information, not medical advice. Talk to your prescriber about your treatment.