Various manufacturers, in association with SAHPRA, have issued the attached communication about the rare risk of a drug reaction with eosinophilia and systemic symptoms (DRESS) associated with aciclovir and valaciclovir. DRESS is a type of delayed hypersensitivity reaction that can occur 2 weeks to 2 months after starting the offending medication. Symptoms include a skin eruption, systemic symptoms (such as fever, lymphadenopathy, haematological abnormalities) and organ involvement (liver injury may occur in as many as 90% of cases).

Read the full letter on the SAHPRA website.