Patient information leaflets for antidepressants: are patients getting the information they need?

According to European law a comprehensive patient information leaflet (PIL) has to accompany all medicines. In this study we examined the uniformity, adequacy and balance of information contained in UK antidepressant PILs.

We studied antidepressant PILs available in the Electronic Medicines Compendium and subjected each to a content analysis. Words were assessed as being positive, negative or neutral.

Forty-two PILs concerning 21 different antidepressants and 23 pharmaceutical companies were studied. PILs presented information about side effects in a strikingly heterogeneous way, making it difficult for patients to find the required information. Half the PILs provided no information about how the antidepressant is thought to work. Over 90% stated the antidepressant would take 2-4 weeks to work, although a few PILs indicated earlier onset of improvement. Not all PILs warned about discontinuation syndrome and advice about alcohol was generally that it was prohibited. Almost half of PILs made no mention of St John's wort and its potential for interaction with the antidepressant. Two-thirds of PILs provided no information about the likely duration of treatment. PILs contained far more words judged to be negative rather than positive or neutral.

Data were extracted by a single researcher, although inter-rater agreement was high.

Further guidance and tightening of the approval process for PILs are needed to ensure they are more standardised in content and contain more information that is wanted by and is useful to patients.