Spectrum and Clinical Burden of Drug-induced Ataxia in Low-resource Settings: An Observational Study

The clinical manifestation of drug-induced ataxia (DIA) is well established clinically but often becomes unrecognized until actual ataxia occurs. DIA may include ataxia as its primary clinical symptom or may be one of multiple manifestations. This study aimed to characterize the development of DIA types and the timing of clinical resolution.

Between January 2016 and March 2025, a prospective observational study of subjects diagnosed with DIA based on the development of ataxia after starting a drug and no prior history of ataxia was conducted. Collected data included the drug involved, timing to onset of symptoms, type of DIA (cerebellar vs sensory), and time required for resolution of symptoms.

A total of 63 subjects met the criteria for inclusion in this analysis. Ataxia was most commonly attributed to antiepileptic drugs (AED) (44 subjects, 69.8%), with the remaining 19 subjects having ataxia after the use of chemotherapeutic or other drugs (30.2%). The most frequent drug associated with ataxia was phenytoin (22 subjects). The majority of ataxia experienced by the subjects was of the cerebellar variety (58.7%), whereas only 41.3% experienced a sensory form of ataxia. Symptoms of ataxia following the use of a drug were most commonly noted >72 hours after starting the drug (79.4%). In subjects with symptomatic improvement after intervention, 39.7% of subjects demonstrated improvement within 72 hours after intervention.

DIA may typically be caused by AEDs and chemotherapeutic drugs, with symptoms commonly manifesting >72 hours after initiation of drug therapy. Early recognition and treatment of DIA may improve clinical outcomes for individuals diagnosed with DIA.