The frequency of photosensitizing drug dispensings in Austria and Germany: a correlation with their photosensitizing potential based on published literature.

BACKGROUND: Drug-induced photosensitivity refers to the development of cutaneous adverse events due to interaction between a pharmaceutical compound and sunlight. Although photosensitivity is a very commonly listed side-effect of systemic drugs, reliable data on its actual incidence are lacking so far. OBJECTIVES: A possible approach to evaluate the real-life extent of drug-induced photosensitivity would be an analysis of the frequency of exposure to a given photosensitizing drug combined with an indicator of its photosensitizing potential. This could serve as a basis for developing a pharmaceutical 'heatmap' of photosensitivity. METHODS: The present study investigated the number of reimbursed dispensed packages of potentially photosensitizing drugs in Germany (DE) and Austria (AT) between 2010 and 2017 based on nationwide health insurance-based databases. In addition, an indicator for the photosensitizing potential was established for each drug based on the number of reports on photosensitivity in the literature. RESULTS: This analysis includes means of 632 826 944 (+/-14 894 918) drug dispensings per year in DE and 113 270 754 (+/-1 964 690) in AT. Out of these, the mean percentage of drugs that enlist photosensitivity as a potential side-effect was 49.5% (±0.7) in DE and 48.2% (±1.2) in AT. When plotting the number of reimbursed dispensed packages vs. the number of reports on photosensitivity, two categories of drugs show high numbers for both parameters, that is diuretics and non-steroidal anti-inflammatory drugs (NSAIDs). CONCLUSIONS: Diuretics and NSAIDs appear to be responsible for the greatest part of exposure to photosensitizing drugs with potential implication on public health.