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Apraxia of lid opening: dose-dependent response to carbidopa-levodopa
Kelly C Lee1, Ron Finley, Bruce Miller
1School of Pharmacy, Loma Linda University, Loma Linda, California, USA.
Abstract:
A 67-year-old woman with an 8-year history of Parkinson's disease and Lewy body dementia experienced difficulty in opening her eyelids (apraxia of lid opening [ALO]); she could close them without difficulty. This problem emerged 2 weeks after the patient's dosage of carbidopa 50 mg-levodopa 200 mg 3 times/day was decreased to twice/day. Two weeks after the onset of ALO the patient visited her physician, who suspected carbidopa-levodopa of causing the problem; the drug was discontinued. When the patient's condition worsened rather than improved, she was referred to a neuro-ophthalmologist, who confirmed the diagnosis of ALO. However, the neuro-ophthalmologist noted that this may not have been a true apraxia but rather a form of sustained blepharospasm that prevented the eyelid from opening. Carbidopa-levodopa was restarted, and her condition improved dramatically when her dosage was increased gradually to carbidopa 50 mg-levodopa 200 mg in the morning and at noon, and carbidopa 25 mg-levodopa 100 mg in the evening. Clinicians should be aware of adverse reactions, such as AOL, in patients taking carbidopa-levodopa who have dementia of the Lewy body type.
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