Adverse psychiatric effects of drugs prescribed for physical illness

Psychiatric adverse drug reactions (ADRs) have been reported with a diverse range of medicines used to treat physical illness. Whereas some are mild (e.g. transient sleep disturbances), others (e.g. psychosis) are severe and warrant discontinuing the suspected causal agents. Some reactions are predictable, while others are unpredictable. The mechanism by which they are mediated is often unclear. It is essential that serious psychiatric ADRs observed during routine clinical practice in the UK are reported via the Yellow Card reporting scheme as relatively uncommon ADRs may only be detected through post-marketing surveillance in the wider population. Patients have reported finding symptoms of psychiatric ADRs extremely distressing and sometimes frightening, and can be hesitant to mention these to clinicians.