Prazosin: Price, Dosage & Where to Buy

Prazosin is an alpha-blocker medicine used to treat high blood pressure, also called hypertension. It relaxes blood vessels to help lower blood pressure, which reduces the risk of cardiovascular events such as strokes and heart attacks. Prazosin requires a prescription in the United Kingdom and can be used alone or alongside other medicines for high blood pressure.

Prazosin is indicated for hypertension, meaning high blood pressure. Lowering blood pressure helps reduce the risk of fatal and non-fatal cardiovascular events, particularly strokes and heart attacks. The label describes blood pressure control as part of wider cardiovascular risk management, which may also include managing cholesterol and diabetes, stopping smoking, exercise and limiting sodium intake.

Prazosin can be used on its own or in combination with other blood pressure medicines, such as diuretics or beta-blockers. Some patients need more than one medicine to achieve their blood pressure goals.

Prazosin belongs to the alpha-blocker group of medicines. These medicines block signals at alpha receptors in the smooth muscle of blood vessel walls. Normally, these signals can cause blood vessels to tighten.

Blocking them allows the vessels to relax and widen, reducing resistance to blood flow and helping lower blood pressure. This effect can also cause blood pressure to drop when a person stands up, which explains why dizziness, lightheadedness or fainting may occur.

The label lists oral capsules containing 1 mg, 2 mg and 5 mg. The usual starting dose is 1 mg two or three times a day. Dosing is adjusted according to the individual's blood pressure response, with gradual increases during treatment.

The label lists maintenance increases to a total daily dose of 20 mg given in divided doses, with commonly used therapeutic doses ranging from 6 mg to 15 mg daily in divided doses. The label lists doses higher than 20 mg as usually offering no increase in efficacy, although a few patients may benefit from up to 40 mg daily in divided doses. The label lists a twice daily regimen as adequate for some patients after initial titration.

The label lists a reduction to 1 mg or 2 mg three times a day when another antihypertensive or a diuretic is added, followed by retitration. These are label facts rather than a personal dosing plan.

A missed dose can interrupt regular blood pressure control. General pharmacy advice is to resume the prescribed schedule rather than doubling a dose to make up for one missed. If several doses have been missed, or there is uncertainty about restarting, ask a pharmacist or prescriber for advice because prazosin can cause dizziness or fainting when treatment begins.

The label does not specify pregnancy or breastfeeding data for prazosin. Discuss its use with a doctor or pharmacist if pregnant, planning a pregnancy or breastfeeding, so that treatment decisions can be considered alongside the need to control blood pressure.

The label specifies storage at 20° to 25°C, protected from moisture and light, in a tight, light-resistant container. Keep the medicine out of children's reach. The unit-dose packaging described in the label is not child resistant.