Exacerbation of myasthenia gravis after amoxicillin therapy: a case series

Introduction Myasthenia gravis (MG) can be aggravated by several classes of drugs, including antibiotics. Penicillins are considered safe drugs for the management of infectious disease in patients with MG. However, a few cases of MG exacerbations after penicillin treatment have been reported in literature. Case reports We report six patients with MG developing acute worsening of symptoms after amoxicillin or amoxicillin/clavulanate treatment. In most of the cases, symptoms started in a few days after antibiotic administration. In all cases, we observed a worsening of the Myasthenia Gravis Foundation of America (MGFA) clinical classification. Most patients required a therapeutic intervention with dosage increase of the previous therapy or the introduction of new drugs for MG. All patients had a full recovery to baseline neurological conditions within 1–2 months. Conclusions We concluded that patients receiving amoxicillin should be closely monitored for possible acute relapse.