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Generic Name: Phenoxybenzamine hydrochloride
Product Name: Dibenyline


Phenoxybenzamine hydrochloride is used to treat high blood in patients that have a phaeochromocytoma. It is also used to help patients with loss of nerve supply to their bladder urinate.


Phenoxybenzamine is an alpha-adrenergic receptor blocking agent that blocks alpha-adrenoreceptors in blood vessels causing them to dilate which results in lowering of the blood pressure. By this mechanism phenoxybenzamine can prevent the intermittent episodes of high blood pressure that can occur in patients with phaeochromocytoma. Phenoxybenzamine also causes the smooth muscle of the bladder and urethra to relax allowing the patient to urinate more easily

Dose advice

Patients with phaeochromocytoma are commenced on an initial dose of 10 mg twice a day. This dose in gradually increased at time intervals of 4 days until the blood pressure is sufficiently controlled or until side effects become a problem.Dosing usually ranges from 20 to 60 mg per day in two divided doses.In patients with urinary retention due to a neurogenic bladder 10 mg is given twice a day. If there has been no response to phenoxybenzamine within 2-3 weeks other treatments should be tried.



Common side effects

Nasal congestionConstriction of pupilsLow blood pressureDizzinessIncreased heart rateInhibition of ejaculation

Uncommon side effects

NauseaVomitingAbdominal painDrowsinessFatigue


For further information talk to your doctor.


Posted On: 22 July, 2003
Modified On: 30 January, 2014

Created by: myVMC
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