Minipress (prazosin) is an alpha blocker originally used to treat hypertension (high blood pressure). While still used to treat hypertension, the medication has also expanded into off-label use for anxiety, post-traumatic stress disorder, and similar conditions. It is also used to aid urination in men who have benign prostate hypertrophy, or an enlarged prostate.

This product is sold under several names other than Minipress, including Hypovase, Vasoflex, and Lentropres, among others.

Effects of Minipress on young patients are unclear. It should not be used in patients under age 18 without explicit doctor approval. Likewise effects on unborn or nursing babies are also unclear; this product should be avoided while pregnant or breastfeeding unless absolutely necessary.

Treating Hypertension

In treating hypertension, Minipress relaxes the walls of blood vessels. Relaxed blood vessels allow blood to flow easier, thus reducing the heart's workload and lowering blood pressure.

Treatment consists of:

• Start with 1 mg taken two or three times per day (2 or 3 mg total per day).
• Dosage may be slowly increased in 1 to 2 mg increments per week, up to 20 mg divided into three daily doses.
• The majority of patients find 6 to 15 mg per day to be suitable.
• Very rarely dosage may be increased to 40 mg per day.
• Do not exceed 40 mg per day.

Other antihypertension medications are often given along with Minipress and will influence its dosage to some degree. Age, weight, and other personal variables may also affect dosage.

Treating PTSD & Anxiety

In PTSD Minipress is most effective at eliminating nightmares and other sleep disturbances. It helps anxious patients remain calm and reduces obsessive worry or thoughts. Treatment typically consists of:

• Start with 1 mg, taken before bed.
• Dosage may be slowly increased in 1 to 2 mg increments per week up to 15 mg per day.
• At higher doses, particularly for anxiety, the total daily dose may be divided into multiple smaller doses taken throughout the day.
• Do not exceed 15 mg per day.

Keep in mind that Minipress will lower blood pressure regardless of what it's used to treat; those with blood pressure on the low side may want to avoid this product.

Aiding Urination

In men with an enlarged prostate urine flow can be severely restricted, leading to frequent, urgent need to urinate but being unable to fully empty the bladder. Minipress is thought to relax the muscles of the urethra and facilitate urination.

Treatment typically consists of:

• Start with 0.5 mg taken twice per day (1 mg total per day).
• Dosage may be slowly increased up to 2 mg taken twice per day (4 mg total per day).
• Do not exceed 4 mg per day.

Again Minipress will lower blood pressure regardless of what it's used to treat; those with blood pressure on the low side may want to avoid this product.

Precautions & Side Effects

Minipress is generally a safe medication if used as directed. Many side effects are related to lowered blood pressure, even if the blood pressure is going from high to healthy ranges. These side effects generally aren't cause for concern and stop occurring after a few weeks of treatment; however, check with a doctor if severe or persistant:

• Drowsiness
• Dizziness
• Fatigue
• Dry mouth
• Nervousness

Rarely more serious side effects develop, which call for medical attention:

• Rapid or pounding heartbeat
• Chest pain
• Difficulty breathing
• Loss of bladder control
• Painful or prolonged erections
• Swelling of feet or legs

Finally, Minipress does interact with certain medications. Of greatest concern are:

• Beta blockers that end in -olol, such as propranolol
• Erectile dysfunction medications that end in -afil, such as sildenafil
• Diuretics

To be on the safe side, always check with a doctor or pharmacist before adding or adjusting dosage of other medications while taking Minipress.