Apomorphine in treatment of Parkinson's disease with fluctuations

Apomorphine is a non-specific dopamine agonist, most similar to it, with a strong action on D2, D3, D4 receptors and weaker action on D1 and D5 receptors. It has been known since 100 years, and in Parkinson's disease it was used first in 1970 by Schwab and Cotzias. Apomorphine is used in Parkinson's disease with high-grade fluctuations of symptoms which cannot be controlled by oral drugs, especially in off" periods resistant to levodopa. After subcutaneous administration it changes the "off" to "on" period within 5-10 minutes. Unfortunately, its effect is short-lasting and wears off after 40-90 minutes. Apomorphine is administered in repeated single subcutaneous injections or in continuous subcutaneous infusion, if more than 7-9 single injections are required daily. Before beginning of treatment the optimal dose of apomorphine should be determined. For counteracting its emetic action domperidon (Motilium) is given additionally 20 mg t.d.s. Apomorphine produces no tolerance and is not losing its effectiveness with continued treatment. The most frequent adverse effects during long-term treatment are local cutaneous reactions, increased intensity of dyskinesia during the "on" period, visual hallucinations whose illusory character is clear to the patient, psychoses, orthostatic hypotension. The authors treated 8 patients with marked fluctuations in Parkinson's disease treated with levodopa. In 7 cases the effects was good--6 of them received 2-3 mg s.c. 3-4 times in 24 hours for 7-12 days. One patient has been treated 9 months with good result. In one case the intensity of dyskinesia made impossible treatment continuation.