Phenoxybenzamine Side Effects
For the Consumer
Applies to phenoxybenzamine: oral capsule
In rats and mice, phenoxybenzamine has been found to increase the risk of development of malignant tumors. It is not known if phenoxybenzamine increases the chance of tumors in humans.
As well as its needed effects, phenoxybenzamine may cause unwanted side effects that require medical attention.
Minor Side Effects
Some phenoxybenzamine side effects may not need any medical attention. As your body gets used to the medicine these side effects may disappear. Your health care professional may be able to help you prevent or reduce these side effects, but do check with them if any of the following side effects continue, or if you are concerned about them:More common:
- Dizziness or lightheadedness, especially when getting up from a lying or sitting position
- fast heartbeat
- pinpoint pupils
- stuffy nose
- dryness of mouth
- lack of energy
- sexual problems in males
- unusual tiredness or weakness
For Healthcare Professionals
Applies to phenoxybenzamine: compounding powder, oral capsule
Cardiovascular side effects have included postural hypotension and tachycardia. These symptoms are evidence of adrenergic blockade and vary according to the degree of blockade.[Ref]
Genitourinary side effects have included inhibition of ejaculation. This symptom is indicative of adrenergic blockade and varies according to the degree of blockade.[Ref]
Respiratory side effects have included nasal congestion. This symptom is indicative of adrenergic blockade and varies according to the degree of blockade.[Ref]
Ocular side effects have included miosis. This symptom is indicative of adrenergic blockade and varies according to the degree of blockade.[Ref]
Nervous system side effects have included drowsiness and fatigue.[Ref]
Gastrointestinal side effects have included gastrointestinal irritation.[Ref]
1. "Product Information. Dibenzyline Capsules (phenoxybenzamine)." SmithKline Beecham, Philadelphia, PA.
It is possible that some side effects of phenoxybenzamine may not have been reported. These can be reported to the FDA here. Always consult a healthcare professional for medical advice.
More about phenoxybenzamine
- Other brands: Dibenzyline
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