Consistency and clarity of pharmacogenomic guidance in UK medicine patient information leaflets: A cross‐sectional analysis

Pharmacogenomic (PGx) information has the potential to support the safe and effective use of medicines, yet there is uncertainty about how this information can be best communicated to patients. Summaries of product characteristics (SmPCs) and patient information leaflets (PILs) for all UK-approved medicines with strong evidence supporting a PGx prescribing recommendation (CPIC Levels A or provisional A/B) were reviewed, using keyword searches to identify relevant content and estimating the reading age of PGx information in PILs using the Flesch-Kincaid grade level. Among 353 products, 281 (80%) SmPCs contained PGx information, but this was reflected in only 115 (33%) PILs. Where present, the PGx content in PILs required an average reading age of 19.1 years, far exceeding the typical UK reading age of 9-11 years. As the availability of genomic data becomes increasingly routine, the variable PGx information provided in PILs risks undermining patient understanding, engagement and safe personalized prescribing.