[Worsened orthostatic hypotension due to levodopa administration in a case of Parkinson's disease]

A 70-year-old woman began to experience gait disturbance in 1995, followed by the appearance of action tremor of the left hand in 1996. This tremor was subsequently noted in the right hand. Her doctor initially diagnosed Parkinson's disease and administered amantadine and levodopa. The gait disturbance and tremor improved. However, she stopped taking the medication and her symptoms worsened in April, 1998. She was admitted to our hospital, and showed rigidity and action tremor predominantly on the left side, frozen gait, postural reflex disturbance and orthostatic hypotension. Following levodopa administration, her UPDRS score improved from 61.3 +/- 1.2 (mean +/- SD) to 41.7 +/- 5.4. However, she experienced a greater decrease in systolic blood pressure following administration upon standing, from 12.5 +/- 5.8 mmHg to 17.8 +/- 9.2 mmHg. Thus, although levodopa administration led to an improvement in rigidity, tremor and akinesia, her orthostatic hypotension worsened. Based on the present results clinicians should be aware of the potential of worsened orthostatic hypotension when prescribing levodopa to treat Parkinson's disease.