on/off phenomena
Last reviewed 01/2018
This phenomenon consists of a sudden loss of anti-Parkinsonian effects of L-dopa and a resulting hypokinesia and rigidity. The loss of effectiveness of L-dopa therapy may last for several hours and can occur irregularly throughout the day.
It is a troublesome symptom which usually develops some time after the patient has been on L-dopa. It is not related to blood levels of L-dopa.
Consider:
- increasing the frequency and decreasing drug dosage.
- a drug holiday
- anticholinergic drugs
- apomorphine by injection