The information provided here is meant to give you a general idea about each of the medicines listed below. Only the most general side effects are included, so ask your doctor if you need to take any special precautions. Use each of these medicines as recommended by your doctor, or according to the instructions provided. If you have further questions about usage or side effects, contact your doctor.
Two main types of medicines are available to treat BPH. One type relaxes the smooth muscle in the prostate and the other kind decreases the amount of hormone that stimulates prostate growth. Symptoms of BPH can also be relieved by antimuscarinics, a group of drugs that work to relax bladder contractions. A phosphodiesterase-5 enzyme inhibitor can also be used to improve urinary tract symptoms.
These medicines lower the tension in the muscular valve at the bottom of the bladder. It makes it easier for urine to pass out of the bladder.
These drugs are generally well-tolerated. The most common side effects are headache, fatigue, and light-headedness. 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 2 different alpha-adrenergic systems, one for the blood pressure and one for the bladder. Tamsulosin, alfuzosin, and silodosin, types of alpha-adrenergic blockers, are specifically targeted at the bladder and prostate. Therefore, they are 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 light-headedness. Alfuzosin has been reported to be associated with less risk of abnormal ejaculation.
Finasteride and dutasteride prevent the formation of the male hormone dihydrotestosterone, which is responsible for the growth of the prostate. These medicines may reduce your symptoms and improve your ability to urinate. Finasteride may also reduce your risk of needing surgery.
Side effects for both of these medicines include changes in your sexual ability or desire and breast enlargement.
These drugs work by reducing the strength of bladder contractions. They may relieve symptoms of urgency and frequency. Side effects include dry mouth, constipation, dry eyes, and confusion. They may also cause increased difficulty emptying the bladder in some patients.
Tadalafil is a medicine that is often prescribed to treat the symptoms of erectile dysfunction. The US Food and Drug Administration (FDA) has recently approved tadalafil as a treatment for BPH, as well. The medicine can reduce symptoms, like difficulty starting to urinate, weak urination stream, and the urge to urinate frequently.
Potential side effects of tadalafil include flushing, headache, stomach upset, back pain, and congestion.
Note: You should not take tadalafil if you are also taking nitrates, because your blood pressure may become dangerously low. Also, tadalafil should not be taken in combination with alpha-blockers.
Research has shown that using alpha-blockers with dihydrotestosterone reducers may work better than using either drug alone in men with larger prostates. This type of therapy, called combination therapy, can decrease the development of complications and the need for surgical intervention. For instance, Jalyn is a medicine that contains both tamsulosin and dutasteride, a dihydrotestorone reducer.
Certain over the counter medicines, notably antihistamines and sleeping pills that contain alpha-adrenergic products, and several kinds of prescription medicines can cause a worsening of urine flow. These medicines can even lead to complete urinary obstruction in patients with BPH. Read labels carefully and check with your physician before you take any new medicines or supplements.
A special precaution is issued for the use of alpha-blockers with medicines used to treat erectile dysfunction. These medicines include:
When taken together, these medicines may cause a drop in blood pressure.
If you are taking medicines, follow these general guidelines:
American Urological Association (AUA) Practice Guidelines Committee. AUA guideline on management of benign prostatic hyperplasia. Available at:
...(Click grey area to select URL)
Accessed September 23, 2020.
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Prostate enlargement: benign prostatic hyperplasia. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/health-topics/urologic-disease/benign-prostatic-hyperplasia-bph/Pages/facts.aspx. Updated September 2014. Accessed September 8, 2017.
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1/4/2011 DynaMed Systematic Literature Surveillance https://www.dynamed.com/condition/benign-prostatic-hyperplasia-bph: Tacklind J, Fink H, et al. Finasteride for benign prostatic hyperplasia. Cochrane Database Syst Rev. 2010;(10):CD006015.
Last reviewed September 2020 by
EBSCO Medical Review Board
Adrienne Carmack, MD
Last Updated: 11/3/2020