Products
Alfuzosin is commercially available in sustained-release tablet form and has been approved in many countries since 1994. In addition to the original Xatral, generic versions are also available.
Structure and properties
Alfuzosin (C19H27N5O4, Mr = 389.45 g/mol) is a quinazoline derivative. It is present in drugs as alfuzosin hydrochloride, a white crystalline powder that is readily soluble in water. Alfuzosin is a racemate.
Effects
Alfuzosin (ATC G04CA01) binds selectively to postsynaptic α1-adrenoreceptors as an antagonist, relaxing prostate and urethral smooth muscle. This increases urinary flow, improves urination and filling symptoms. The effects are rapid, within hours to days, compared to 5alpha-reductase inhibitors. Alfuzosin has no effect on prostate size; it is only effective against symptoms. Alfuzosin may lower blood pressure (see Adverse Effects).
Indications
Symptomatic treatment of functional disorders of benign prostatic hyperplasia.
Contraindications
- Hypersensitivity
- Pre-existing orthostatic hypotension
- Concurrent administration of other alpha blockers.
- Severe hepatic insufficiency
Full precautions can be found in the drug label.
Interactions
Alfuzosin is metabolized primarily by CYP3A4. Combination with other alpha blockers is contraindicated. Other antihypertensives and nitrates may result in an increased decrease in blood pressure. Strong CYP3A4 inhibitors may increase concentrations of alfuzosin. Other interactions are possible with diltiazem and narcotics.
Adverse effects
Alpha blockers were originally developed for the treatment of high blood pressure. Alfuzosin can also frequently lower blood pressure and lead to orthostatic hypotension. As a result, side effects such as loss of consciousness, drowsiness, weakness, dizziness, malaise, and headache can often occur. Palpable heartbeats and a rapid pulse are rare. Indigestion is common.
