5-Alpha Reductase Inhibitors for Benign Prostatic Hyperplasia

5-alpha reductase inhibitors reduce the size of the prostate. But since a smaller size does not always relieve symptoms, these medicines will not give satisfactory results in every case. When you stop taking the medicine, symptoms usually return.

5-alpha reductase inhibitors lower prostate-specific antigen (PSA) levels. Because PSA levels are used to detect early-stage prostate cancer, men interested in taking a 5-alpha reductase inhibitor might consider the following:

• Most experts suggest that men be checked for the presence of prostate cancer (using the PSA test and a digital rectal exam) before taking 5-alpha reductase inhibitors.
• Follow-up PSA levels that have not decreased by approximately 50% after 6 months of taking a 5-alpha reductase inhibitor may point to the need for further testing for prostate cancer.
• PSA levels above 2 ng/mL (nanograms per milliliter) during 5-alpha reductase inhibitor treatment may point to the need for further testing for prostate cancer.

5-alpha reductase inhibitors are not recommended for treatment of BPH symptoms in men who do not have an enlarged prostate.^{Reference 1}

The medicine must be taken for the rest of your life to prevent the symptoms from coming back.

This medicine should not be used by men who plan to father a child, because there is a small chance that the medicine could cause a birth defect. Women who are pregnant or might become pregnant should not handle broken or crushed tablets of finasteride or dutasteride.

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