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 NICE CKS. Itraconazole also passes into breast milk in small amounts and is generally advised against during breastfeeding NICE CKS. 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 NICE CKS. 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 & Lyons 2014. Additionally, fluconazole can cause photosensitivity and has potential drug interactions due to cytochrome P450 enzyme inhibition Gupta & 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 NICE CKS. Overall, while systemic antifungals are effective for pityriasis versicolor, their use requires careful consideration of potential systemic side effects, monitoring, and patient-specific factors NICE CKS Gupta & Lyons 2014.