Drug Safety & Side-Effect Checker
Drug-safety reference, with its sources shown
A source-labelled reference for side effects and safety information — clear about its limits, and where to go for decisions.
Safety first. Education and reference only — not for prescribing or interaction decisions. Always use the BNF, SmPC and local formulary, and apply clinical judgement. To report a suspected adverse reaction, use the MHRA Yellow Card scheme.
Coming online. The searchable safety index is being connected to permitted public sources. Meanwhile, consult the BNF and the product SmPC.
How we present safety information
Clear hierarchy, clear limits
- Source hierarchyAuthoritative sources first, with provenance labels.
- Data freshnessEach entry shows a last-reviewed date.
- Reporting routesDirect links to the MHRA Yellow Card scheme.
What this resource is for
A reference layer, not a prescribing tool
Side-effect and interaction information is among the most safety-critical content on the web, and also among the most poorly sourced. Plenty of sites present a confident list of adverse effects or a red-amber-green interaction grid with no indication of where the data came from or when it was checked. That is precisely the kind of resource a clinician should not lean on. This checker is built to be honest about what it is: a source-labelled reference that helps you orient yourself, paired with clear signposting to the authoritative sources where actual prescribing and interaction decisions belong — the BNF, the Summary of Product Characteristics for the specific product, and your local formulary.
The searchable index above is being connected to permitted public sources so that, when live, every entry will carry a provenance label and a last-reviewed date. Until then, the tool is deliberately conservative: rather than show partial or unverified data, it points you to the BNF and the product SmPC. We would rather say "not yet" than risk giving you a number you cannot trace.
Reporting and escalation
If you suspect an adverse drug reaction
This tool is not a route for reporting adverse events. In the UK, suspected adverse drug reactions should be reported through the MHRA Yellow Card scheme, which underpins post-marketing safety surveillance. Reporting matters even when you are not certain the medicine was responsible — the scheme is designed to capture suspicions, and patterns across many reports are how new safety signals are detected. Patients, carers and healthcare professionals can all submit a Yellow Card.
How it works alongside our other tools
For the descriptive information on a medicine — what it is, what it treats — use the Medicine Finder, which draws on the NHS Medicines A–Z. When a calculator or clinical score directs you towards a drug, you can move between the finder and this checker to build a fuller picture, always confirming the detail against the SmPC. For the principles behind how we label and date safety content, see our Quality & Editorial Policy.
Education and reference only. This resource does not replace official product labelling and must not be used to make prescribing or interaction decisions. Always apply clinical judgement and verify against the BNF, the SmPC and local guidance.
Answers
Frequently asked questions
Can I use this to check interactions for a patient?
No. This is an education and reference resource only. For prescribing and interaction decisions, always use authoritative sources — the BNF, the Summary of Product Characteristics (SmPC) and your local formulary — and apply clinical judgement.
How do I report a suspected side effect?
In the UK, report suspected adverse drug reactions via the MHRA Yellow Card scheme (yellowcard.mhra.gov.uk). This tool is not a route for reporting adverse events.
Where does the information come from?
Content draws on permitted public sources with provenance labels and last-reviewed dates. It does not replace official product labelling.
Why does the search say it is still coming online?
We connect the index to permitted public sources before publishing entries, so that each one can carry a provenance label and a last-reviewed date. Rather than show partial or unverified data in the meantime, we point you to the BNF and the product SmPC.
What is the difference between this and the Medicine Finder?
The Medicine Finder gives descriptive reference information on a medicine. This checker focuses on side-effect and safety content and on reporting routes. Both are reference tools; neither replaces the SmPC, the BNF or clinical judgement.
Building a safety tool?
We help teams integrate permitted, source-labelled safety content responsibly.