Cartucho Joana, Bonito Bruno, Rodrigues Barbosa Bruna, Fernandes Carla, Fernandes Martinho
Internal Medicine, Unidade Local de Saúde do Arco Ribeirinho, Barreiro, PRT.
Cureus. 2025 Jul 15;17(7):e87981. doi: 10.7759/cureus.87981. eCollection 2025 Jul.
Fluoroquinolones are widely used antibiotics due to their broad-spectrum activity and favorable pharmacokinetic properties. However, increasing evidence has raised concerns about their neurotoxic potential, particularly in vulnerable populations. We present a case of a 63-year-old woman with a history of pulmonary fibrosis and depression, treated chronically with aminophylline and fluvoxamine, who presented with a generalized tonic-clonic seizure after repeated courses of moxifloxacin. No other metabolic, structural, or toxicological causes were identified. Neurological evaluation and imaging were unremarkable. Following discontinuation of moxifloxacin, there was no recurrence of seizure activity. Although considered safer among the newer fluoroquinolones, moxifloxacin may induce seizures through gamma-aminobutyric acid type A (GABA-A) antagonism and N-methyl-D-aspartate (NMDA) stimulation, particularly in patients with risk factors such as polypharmacy and prolonged exposure. This case highlights the need for increased clinical vigilance even in younger patients without renal or hepatic impairment. Moxifloxacin-associated seizures, though rare, must be considered in the differential diagnosis of new-onset seizures, especially in patients exposed to prolonged or repeated fluoroquinolone therapy.