Myoclonic attacks induced by L-dopa and bromocryptin in Parkinson patients: a sleep EEG study.

Six patients with Parkinson's disease developed nocturnal myoclonic attacks after prolongued treatment with L-Dopa which were electroencephalographically recorded. These symptoms persisted after treatment with 2 bromo-alpha-ergocryptin (Bromocryptin), a dopamine receptor agonist, which was substituted for L-Dopa. Bromocryptin is known to have no pre- or postsynaptic effect on serotonin metabolism. It is proposed that these myoclonic phenomena are the expression of the hypersensitivity of denervated catecholamine receptors in the brainstem to the stimulation of L-Dopa and Bromocryptin. This thesis differs with previous suggestions that serotonin plays a major role in the genesis of myoclonic seizures in Parkinsonian patients treated with L-Dopa.