Glossary term

Interaction: Interaction is the plain-language term for one medicine, substance or health factor changing the effect or safety of another.

EssentialClinicalSource quality: HighLast updated: 29 June 2026

Why this term matters

Patients use and search this wording more often than “drug-drug interaction”.

UK medical cannabis context

NICE tells prescribers to consider current and past cannabis use, online products and interactions with other medicines.

What not to assume

Interactions may involve OTC medicines, alcohol, supplements or illicit products as well as prescriptions.

Careful wording: Avoid assuming only prescribed medicines matter.

Related glossary terms

Related MCPH pages

Sources and review notes

This entry is educational vocabulary, not medical advice. Suitability, prescribing, product choice and monitoring belong with a qualified clinician or pharmacist.