Friedberg A, et al. - In patients with multiple system atrophy parkinsonism (MSA-P), researchers evaluated clinical response to 5 consecutive days of high-dose intravenous (IV) amantadine. Study participants were 14 patients diagnosed with MSA-P treated with IV amantadine. Using the Unified Multiple System Atrophy Rating Scale, patients' disease severity before and after therapy was assessed. Clinical improvement was seen in 10 patients. It was noted that adverse events were minor and temporary, except for in one subject, who experienced acute psychosis, which prompted the cessation of treatment, after which the psychosis resolved. The findings from the present study suggested that IV amantadine could be a safe and efficacious therapy in MSA-P.