Hytrin can cause orthostatic hypotension which may be severe and produce syncope after the initial dose; it may be preceded by tachycardia. This reaction can be avoided by starting treatment with a low dose, preferably at night. The hypotensive effects may be exaggerated by exercise, heat, or alcohol ingestion.

The more common adverse effects include dizziness, drowsiness, headache, lack of energy, nausea, and palpitations, and may diminish with continued HYTRIN therapy in Kenya or with a reduction in dosage. Other adverse effects include oedema, chest pain, dyspnoea, constipation, diarrhoea, vomiting, depression and nervousness, sleep disturbances, vertigo, hallucinations, paraesthesia, nasal congestion, epistaxis, dry mouth, urinary frequency and incontinence, reddened sclera, blurred vision, tinnitus, abnormal liver enzyme values, pancreatitis, arthralgia, alopecia, lichen planus, skin rashes, pruritus, and diaphoresis. Impotence and priapism have also been reported.