A.P. is a 68-year-old male from Indiana that was diagnosed with stage I Parkinson’s Disease 18 months ago. He has been treated with pramipexole 1.0 mg TID since his diagnosis, and states that, with this treatment, he experienced a decrease in bothersome symptoms, as evidenced by his increased ability to write in the answers to his crossword puzzle and hold his playing cards during his weekly card club. He is in Arizona for the winter, and comes to you today because he has noticed a gradual worsening of his symptoms and is once again having difficulty holding a pencil and writing. He also complains that he feels more “tied up”, and his wife tells you that his posture has become more stooped.
- How would you recommend altering A.P.’s treatment plan at this time? Include dosing parameters.
A.P. experienced a dramatic improvement in all of his parkinsonian symptoms with the initiation of the therapy you recommended (which, for this next question, we are going to say was dosed immediate-release). However, after six months, he begins to experience dyskinesias. These usually occur 1-2 hours after a dose and were manifested by facial grimacing, lip smacking, tongue protrusions, and rocking of the trunk. His HCP in Indiana gradually decreased the dose of his medications, which lessened the dyskinetic effects, but they did not totally clear. Now, after three more years of therapy, A.P. is back in Arizona for the winter, and more serious problems have begun to emerge. In the mornings, A.P. often experiences immobility. Nearly everyday he has periods in which he cannot move, followed by a sudden switch to a fluid-like state, often associated with dyskinetic activity. He continues to take the drug you prescribed, but only gains symptomatic relief for about 3-4 hours after a dose. Also, the response to a given dose varies and is often less in the afternoon. He complains that he often becomes “frozen” when he needs to move quickly, such as when he got off the escalator at the airport.
- What do you recommend for A.P. to help with these continuing motor fluctuations?
A.P. returns six months later and reports that his dyskinetic activity has lessened. However, he is still having periods in which he cannot move that last a few minutes. He is currently taking pramipexole 0.5 mg TID, Sinemet CR QID (Sinemet 50/200), and immediate-release levodopa/carbidopa 25/100 QD. However, he states that even on a good day he gains symptomatic relief for only about 2-3 hours following a dose. He also tells you that he has been having visual hallucinations and nightmares.
- What would you recommend to improve R.Q.’s symptoms?
- How should this regimen be initiated (i.e. dosing)?
- Describe the mechanism of action for this regimen.