What are the potential side effects of systemic antifungal treatments for pityriasis versicolor?

Systemic antifungal treatments commonly used for pityriasis versicolor include oral itraconazole and fluconazole. Potential side effects of these systemic antifungals primarily relate to their systemic absorption and metabolism. Fluconazole is known to be excreted into breast milk in significant amounts, warranting caution in breastfeeding mothers, especially preterm infants, due to limited safety data ¹. Itraconazole also passes into breast milk in small amounts and is generally advised against during breastfeeding ¹. Both drugs can cause adverse effects such as gastrointestinal disturbances, headache, and potential hepatotoxicity, although specific side effect profiles are not extensively detailed in the UK guidelines for pityriasis versicolor ¹. From broader pharmacological knowledge and literature, systemic azole antifungals like itraconazole and fluconazole may also cause liver enzyme elevations, rash, and, rarely, more severe hepatic injury (Gupta and Lyons, 2014). Additionally, fluconazole can cause photosensitivity and has potential drug interactions due to cytochrome P450 enzyme inhibition (Gupta and Lyons, 2014). The UK guidelines emphasize the need for specialist advice when considering systemic antifungals in children, pregnant or breastfeeding women, reflecting concerns about safety and side effects ¹. Overall, while systemic antifungals are effective for pityriasis versicolor, their use requires careful consideration of potential systemic side effects, monitoring, and patient-specific factors ¹ (Gupta and Lyons, 2014).