naloxone and Urinary-Bladder--Neurogenic

The effects of opioid blockade with the potent opiate/opioid antagonist, naloxone, on detrusor function are described. In a double-blind placebo-controlled trial of 28 patients, naloxone caused an increase in detrusor instability together with an increase of detrusor pressure during filling cystometry and a decrease in maximum cystometric capacity. The significance of these findings for the etiology of idiopathic detrusor instability is discussed.

Topics: Adult; Aged; Clinical Trials as Topic; Double-Blind Method; Endorphins; Female; Humans; Male; Middle Aged; Muscle Contraction; Muscle, Smooth; Naloxone; Receptors, Opioid; Urinary Bladder; Urinary Bladder, Neurogenic

Topics: Humans; Naloxone; Spinal Cord Injuries; Urinary Bladder, Neurogenic

Naloxone has been reported to facilitate detrusor activity by blocking the inhibitory action of the enkephalins. We tested the urodynamic effects of intravenous naloxone (0.4 to 0.8 mg.) in 15 patients with spinal cord injury via rapid fill carbon dioxide cystometry and perineal electromyography. Fourteen patients had suprasacral lesions (3 complete), while 1 had an incomplete lower cord lesion. The average interval from injury was 4.2 months. Most of the patients were managed with intermittent catheterization and most had chronic bacteriuria. Initially, 10 patients had detrusor areflexia and 5 had detrusor hyperreflexia (2 with dyssynergia). Of the 15 patients 14 had no neuropathic condition as noted on baseline electromyography. After naloxone injection no significant cystometrographic changes occurred but 11 patients (73 per cent) had decreased electromyographic activity. The vesicourethral pattern of the 2 patients with dyssynergia did not change after naloxone, even though the electromyographic response decreased in both. The patients showed no other effects of the naloxone administration. Contrary to other studies, naloxone seemed to diminish pelvic floor (electromyographic) activity but it did not change bladder (cystometrographic) function during bladder rehabilitation of spinal cord injury patients.

Topics: Adult; Aged; Electromyography; Enkephalins; Humans; Male; Middle Aged; Naloxone; Pressure; Spinal Cord Injuries; Urinary Bladder; Urinary Bladder, Neurogenic; Urinary Catheterization; Urodynamics

An intravenous injection of 0.4 mg. naloxone enhanced detrusor reflex activity in 5 patients with chronic neurogenic bladder dysfunction caused by incomplete suprasacral spinal lesions. The intravesical volume at which detrusor reflex occurred showed a decrease from 498.2 to 346.2 ml. The naloxone-induced effect was short-lived, being absent 1 hour after the injection. In the same dosage naloxone did not induce detrusor reflex in 2 patients with areflexic bladder caused by complete suprasacral spinal lesions.

Topics: Adolescent; Adult; Aged; Female; Humans; Male; Middle Aged; Muscle, Smooth; Naloxone; Reflex; Stimulation, Chemical; Urinary Bladder; Urinary Bladder, Neurogenic