What is meant by ON and OFF periods?
Variation in motor performance is characterised as ON or OFF.
- ON refers to the state a patient is in when their symptoms are well controlled and function is as normal as possible for them.
- OFF is when a patient feels weak and finds it difficult to move, symptoms tend to resurface.
The transition between ON and OFF can occur when a anti-Parkinson’s drug dose begins to wear off, usually before the next dose is imminently due.
Modified release drug preparations may help reduce end of dose deterioration.(7)