Glossary term

Behavioural side effect: This term refers to unwanted changes in mood, behaviour or thinking that may occur while taking a medicine. NHS information on medical cannabis includes mood and behavioural changes among possible side effects.

UsefulSafetySource quality: HighLast updated: 29 June 2026

Why this term matters

Important because some patients and carers notice behaviour changes before physical side effects.

UK medical cannabis context

NHS specifically lists behavioural or mood change, hallucinations and suicidal thoughts among possible side effects.

What not to assume

New agitation, distress, severe anxiety, suicidal thoughts or hallucinations warrant urgent clinical advice.

Careful wording: Avoid normalising serious psychiatric symptoms.

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.