Roponirole(Requip)

All of us know that there is a deficiency of dopamine in the brain of patients who suffer from Parkinson's Disease (PD). Dopamine is a chemical substance that is present in the brain cells. It is basically a "messenger" that carries information from one brain cell to another. The transmission of these 'messages' is important for the co-ordination and execution of normal movement of the body.

The deficiency of dopamine causes a breakdown in the communication between brain cells and leads to the symptoms of PD such as tremor (trembling of hands and feet), stiffness and slowness of movement.

Dopamine agonists (DA's) are medications which increase the activity of dopamine in the brain, leading to improvement in the symptoms of PD.

What is the role of Ropinirole?

a) Symptomatic relief

Ropinirole, one of the relatively new DA's, has been shown to improve the daily performance of Parkinson's patients (Whone AL et al, 2003).

b) Motor complications

Motor complications such as dyskinesia (involuntary, "swinging" body movement) have been recognized as one of the long term complications in PD. Dyskinesia can be severe and disabling. Once established, dyskinesia is irreversible (persists for life). It is often difficult to treat dyskinesia with medications. Thus, prevention of dyskinesia is one of the most important principles in the treatment of PD.

Ropinirole has been shown to reduce the incidence of motor complications (Rascol O, et al; 2000). This is the main reason why the American Academy of Neurology (Olanow CW et al, 2001) has recommended that DA's should be the preferred drug of first choice in the initial treatment of PD, especially the younger patients (age < 60).

c) Protection of brain cells

Being an incurable illness, it is worthwhile trying to slow down the disease progression in PD. By protecting the brain cells from damage, it may be possible to slow down the progression of PD. A study had shown that Ropinirole may potentially slow down the disease progression in PD (Whone AL et al, 2003). It has to be emphasized that the protective effect of Ropinirole in PD has not been confirmed. However, the findings of this study are encouraging.

How to start taking Ropinirole?

It is available in three different dosages: 0.25 mgs, 1 mg and 2 mgs pills. The 0.25 mgs pills are given as the "starter pack" which provides clear instruction on the how to gradually increase the dose. In the starter pack, Ropinirole is started as one tablet thrice a day for one week, two tablets thrice a day for the second week, three tablets thrice a day for the third week and four tablets thrice a day for the fourth week.

By the fifth week, patients can take one tablet of the 2 mgs pills thrice a day (total of 6 mgs a day). By the sixth week, the daily dose can be increased to two tablets of 2 mgs pills thrice a day (total of 12 mgs a day), if necessary.

Generally, most Parkinson's patients will respond well to 2-4 mgs of Ropinirole thrice a day.

What are the side effects of Ropinirole?

These are nausea, vomiting, dizziness and sleep attacks. It has to be emphasized that side effects of Ropinirole are rare because the dose is increased in a gradual manner. Sleep attacks are rare side effects which are characterized by falling asleep in unusual circumstances such as during driving and working. Ropinirole has also been associated with tendency for gambling and increased sexual drive, which are also rare (and probably over-publicized).

Ropinirole-PD

This is a new formulation of Ropinirole, which is the longer-acting version. Ropinirole-PD will arrive in Malaysia by 2009. It is taken as once daily dosage, which is much more convenient for Parkinson's patients.

References

Olanow CW, Watts RL and Koller WC. An algorithm (decision tree) for the management of Parkinson's Disease (2001): treatment guidelines. Neurol 2001; 56(11) Suppl 5: S1-S88.?

Rascol O, Brooks DJ, Korczyn AD, DeDeyn PP, Clarke CE, Lang AE. A five-year study of the incidence of dyskinesia in patients with early Parkinson's disease who were treated with ropinirole or levodopa. 056 Study Group. N Engl J Med 2000; 342: 1484-1491.