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.
No match in our guides yet. Consult the BNF and the product SmPC for safety detail.
Opens our clinically-reviewed guide for that medicine or class — each sets out key safety, who should not use it, what to monitor and the main interactions. For prescribing, interaction and dosing decisions, always use 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 search above opens our own clinically-reviewed guides, each of which sets out the key safety points, who should not take a medicine, what is monitored and the main interactions — referenced and dated. What it deliberately does not do is hand you a specific dose or a definitive interaction grade: those belong with the BNF, the product SmPC and clinical judgement. We would rather point you to the authoritative source 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 searches the same library of clinically-reviewed guides. 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?
The search opens our own clinically-reviewed guides — original content referenced to the BNF, SmPC and UK health system and carrying a last-reviewed date. It does not replace official product labelling, and exact doses and interaction decisions belong with the BNF, the SmPC and your prescriber.
Does it give me a number for a dose or an interaction grade?
No — and that is deliberate. Our guides explain the key safety considerations, who should avoid a medicine, what is monitored and the main interactions in plain terms, but specific doses and definitive interaction grading must come from the BNF, the product SmPC and clinical judgement. A confident number with no traceable source is exactly what we will not show.
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.