Neurogenic bladder frequently occurs in Parkinson's disease. Detrusor hyperreflexia is a consequence of nigrostriatal dopamine depletion, whereas the cause of hyporeflexia remains unclear. We compared the results of cystometry and urethral profilometry with and without apomorphine (and L dopa) in 12 idiopathic parkinsonians with urinary disorders free of dopaminergic treatment. Whereas hyperreflexic patients improved with apomorphine, and to a lesser extent with L dopa, these drugs had no effect on hyporeflexic patients. These results confirm the role of dopaminergic lesions in the occurrence of bladder hyperreflexia and the possible implication of nondopaminergic lesions in the occurrence of hyporeflexia.