methylcellulose and naxagolide

Dopaminergic agonists are drugs that directly stimulate the dopamine receptors of the striatum and have proved useful in treating Parkinson's disease. In the United States, they are primarily used in conjunction with levodopa. Most have long half-lives and have been particularly useful in controlling and attempting to prevent motor fluctuations.

Topics: Apomorphine; Bromocriptine; Dopamine Agents; Humans; Lactose; Lisuride; Methylcellulose; Oxazines; Parkinson Disease; Pergolide; Receptors, Dopamine

MK 458 is a potent and selective D2 receptor agonist. MK 458 consists of (+)-4-propyl-9-hydroxynaphthoxazine (PHNO) in a hydroxypropyl-methylcellulose-lactose matrix. MK 458, mean dose 8.1 mg (range 2.5 to 13.5 mg), was administered to 14 patients with advanced Parkinson's disease (PD) who were no longer satisfactorily responding to levodopa. The duration of the study was 4 weeks with a titration to maximum dose in 2 weeks. The addition of MK 458 resulted in a mean reduction in levodopa of 41% (range 0 to 81%). This degree of levodopa reduction was not seen in previous studies with other DA agonists. While the reduction in signs of PD was comparable to those on levodopa, MK 458 did not induce dyskinesias or dystonias. It is postulated that MK 458 may be able to replace levodopa as the primary treatment for PD.

Topics: Adult; Aged; Antiparkinson Agents; Carbidopa; Dopamine Agents; Female; Humans; Hypromellose Derivatives; Lactose; Levodopa; Lisuride; Methylcellulose; Middle Aged; Nausea; Oxazines; Parkinson Disease; Pergolide; Psychomotor Performance; Receptors, Dopamine