Recurrent amoxicillin-induced aseptic meningitis.

A woman in her 70s presented to the emergency department with a 1 day history of headache, sore throat and neck pain after taking prophylactic amoxicillin for dental work. She had two prior hospitalisations for presumed viral meningitis. Examination was unremarkable except for neck extension pain. Labs showed neutrophil predominance (92.8%) with cerebrospinal fluid lymphocytosis and elevated protein. CT revealed a 3 mm right tonsillar abscess. Initially improving with symptomatic care, she later developed vomiting, headache and fever after receiving Augmentin for the abscess, inadvertently confirming an amoxicillin allergy. She was discharged after 72 hours but re-presented with persistent symptoms and was ultimately discharged on hospital day 5. At follow-up, she reported residual weakness and fatigue. Amoxicillin-induced aseptic meningitis is rare but should be considered in patients with non-specific meningoencephalitis symptoms after amoxicillin exposure. Diagnosis relies on symptom timing and exclusion of other causes, with management involving discontinuation and supportive care.