The information provided here is meant to give you a general idea about each of the medications listed below. Only the most general side effects are included, so ask your healthcare provider if you need to take any special precautions. Use each of these medications as recommended by your healthcare provider, or according to the instructions provided. If you have further questions about usage or side effects, contact your healthcare provider.

A couple of types of medication are available to treat less advanced cases of BPH. One type weakens the muscular valve that holds urine in; the other kind decreases the amount of hormone stimulating prostate growth.

Prescription Medications

Alpha1-adrenergic Blockers

  • Prazosin (Minipress)
  • Doxazosin (Cardura)
  • Terazosin (Hytrin)
  • Tamsulosin (Flomax)
  • Alfuzosin (Uroxatral)

Dihydrotestosterone Reducers

  • Finasteride (Proscar)
  • Dutasteride (Avodart)

Alpha1-adrenergic Blockers

  • Prazosin (Minipress)
  • Doxazosin (Cardura)
  • Terazosin (Hytrin)
  • Tamsulosin (Flomax)

Prazosin, Doxazosin, and Terazosin were developed to treat high blood pressure. However, the same effect that lowers blood pressure lowers the tension in the muscular valve at the bottom of the bladder, making it easier to pass urine. Over two-thirds of patients with BPH who take these drugs experience rapid improvement in their symptoms without negative effects on their blood pressure.

These drugs are generally well tolerated. The most common side effects are headache, fatigue, and dizziness. A "first dose" effect may occur that causes blood pressure to drop, which may result in fainting. For this reason, it is recommended that the first pill be taken at bedtime.

There are two different alpha-adrenergic systems, one for the blood pressure and one for the bladder. Tamsulosin (Flomax), a type of alpha-adrenergic blocker, is specifically targeted at the bladder and prostate. Therefore, it's less likely to cause low blood pressure or fainting, although these adverse effects can still occur. Other side effects include runny nose, abnormal ejaculation, fatigue, and dizziness. Alfuzonsin (Uroxatral) has been reported to be associated with less risk of abnormal ejaculation.

Dihydrotestosterone Reducers

  • Finasteride (Proscar)

Finasteride prevents the formation of the male hormone dihydrotestosterone that is responsible for the unrelenting and continued growth of the prostate. The effect of finasteride is slower than the other agents. About 50% of people taking it for 12 months experience improvement. Similar results have been reported for dutasteride. This drug may achieve the desired improvement in voiding function over a shorter duration than Finasteride.

Finasteride is the only medication that reduces the progression of the disease. Under the name Propecia, this same drug is used to treat male pattern baldness.

Special Considerations

Certain over-the-counter medications, notably antihistamines and sleeping pills which contain alpha adrenergic products and several kinds of prescription medicine (anticholinergic and narcotic) can cause a worsening of urine flow. These medications can even lead to complete urinary obstruction in patients with BPH. Read labels carefully and check with your physician before you take any new medications or supplements.

Special Considerations

Whenever you are taking a prescription medication, take the following precautions:

  • Take them as directed—not more, not less, not at a different time.
  • Do not stop taking them without consulting your healthcare provider.
  • Don’t share them with anyone else.
  • Know what effects and side effects to expect, and report them to your healthcare provider.
  • If you are taking more than one drug, even if it is over-the-counter, be sure to check with a physician or pharmacist about drug interactions.
  • Plan ahead for refills so you don’t run out.