Why take tamsulosin and finasteride together? Understanding Combination Therapy for BPH

October 7, 2025 •

3 min read

Benign prostatic hyperplasia (BPH) affects up to 60% of men by age 60, with symptoms like frequent and urgent urination. For men with moderate to severe symptoms and an enlarged prostate, doctors may prescribe a powerful dual-action treatment: the combination of tamsulosin and finasteride.

Quick Summary

Taking tamsulosin and finasteride together offers a comprehensive approach to managing benign prostatic hyperplasia by providing both immediate symptom relief and long-term prostate size reduction. Clinical studies confirm this combination is significantly more effective than using either medication alone for slowing disease progression.

Key Points

Complementary Action: Tamsulosin offers rapid relief by relaxing prostate muscles, while finasteride provides long-term benefits by shrinking the prostate gland.
Superior Efficacy: Major clinical trials have shown that the combination of tamsulosin and finasteride is more effective at improving symptoms and preventing BPH progression than either drug alone.
Addresses Cause and Symptoms: This therapy is ideal for men with moderate to severe BPH who need both immediate relief and a solution that addresses the root cause of the enlarged prostate.
Reduces Risk of Complications: The combination significantly lowers the long-term risk of acute urinary retention and the need for BPH-related surgery.
Potential for Side Effects: While effective, the combination can lead to a higher rate of adverse events, including dizziness and sexual dysfunction, compared to single-drug therapy.
Regular Monitoring is Key: Doctors must carefully monitor prostate-specific antigen (PSA) levels in patients on finasteride, as the drug can alter these test results.

Understanding Benign Prostatic Hyperplasia (BPH)

Benign prostatic hyperplasia, or BPH, is a non-cancerous enlargement of the prostate gland common in aging men. This enlargement can constrict the urethra, leading to lower urinary tract symptoms (LUTS) such as:

Frequent or urgent urination
Increased nighttime urination
Weak urine stream
Incomplete bladder emptying

While mild symptoms might be managed with lifestyle adjustments, moderate to severe cases often require medical treatment. Combination therapy using two drugs with different actions can be more effective than single-drug treatments for many patients.

How Tamsulosin Works for BPH

Tamsulosin (Flomax) is an alpha-blocker that relaxes muscles in the prostate and bladder neck. This relaxation reduces pressure on the urethra, improving urine flow. It provides rapid symptom relief within days to weeks but does not reduce prostate size.

How Finasteride Works for BPH

Finasteride (Proscar) is a 5-alpha reductase inhibitor that blocks the conversion of testosterone to DHT, a hormone that promotes prostate growth. By lowering DHT, finasteride shrinks the prostate over 6 to 12 months, addressing the underlying cause of enlargement.

Why Take Tamsulosin and Finasteride Together?

Combining tamsulosin and finasteride is often prescribed for men with moderate to severe BPH and an enlarged prostate due to their complementary actions. This approach offers both rapid symptom relief from tamsulosin and long-term prostate shrinkage from finasteride. This dual treatment helps prevent or slow BPH progression and reduces the risk of complications like acute urinary retention or the need for surgery.

Clinical Evidence for Combination Therapy

Studies like the MTOPS trial (doxazosin/finasteride) and the CombAT study (tamsulosin/dutasteride) support combination therapy. MTOPS showed combination therapy significantly reduced BPH progression risk compared to either drug alone. CombAT found tamsulosin and dutasteride together were superior to monotherapy for improving symptoms and quality of life.

Benefits and Considerations of Combination Therapy

Combination therapy offers greater symptom improvement, significant prostate size reduction, and a decreased risk of BPH progression and surgery. However, it may increase the likelihood of side effects such as dizziness or sexual dysfunction. Finasteride also lowers PSA levels, requiring careful monitoring by a doctor for accurate prostate cancer screening. Finasteride can also be present in semen and requires precautions to avoid exposure to pregnant women.

Tamsulosin vs. Finasteride vs. Combination Therapy


Feature	Tamsulosin (Alpha-Blocker)	Finasteride (5-ARI)	Combination Therapy
Mechanism	Relaxes muscles in prostate and bladder neck	Blocks DHT to shrink the prostate	Relaxes muscles and shrinks the prostate
Onset of Action	Rapid (days to weeks)	Slow (6-12 months)	Rapid symptom relief, long-term prostate shrinkage
Primary Effect	Symptom relief, improves urine flow	Reduces prostate size, prevents progression	Comprehensive: symptom relief + disease modification
Effect on Prostate Size	None	Significant reduction over time	Significant reduction over time
Best for	Immediate relief, smaller prostates	Larger prostates, long-term management	Moderate to severe symptoms, enlarged prostate
Common Side Effects	Dizziness, retrograde ejaculation, low blood pressure	Sexual dysfunction (low libido, ED), ejaculation issues	Combines side effects of both medications

Conclusion

Combining tamsulosin and finasteride offers a comprehensive approach for men with moderate to severe BPH and an enlarged prostate. This therapy provides rapid symptom relief while also addressing the underlying cause by shrinking the prostate gland. Clinical trials demonstrate its superior effectiveness in improving symptoms and reducing complications compared to single-drug treatments. Patients should discuss this option with their doctor to weigh the benefits and risks based on their individual health needs.

How to get started

Consulting a healthcare provider is recommended for more information on BPH treatments. The American Urological Association's website offers additional resources. American Urological Association

Disclaimer: The information in this article is for informational purposes only and does not constitute medical advice. Consult with a qualified healthcare professional before making any decisions about your health or treatment.

Frequently Asked Questions

Tamsulosin typically starts to improve urinary symptoms within days to weeks. Finasteride, however, works much more slowly and can take 6 to 12 months to show its full effect by shrinking the prostate.

It is crucial not to stop taking either medication without consulting your doctor. If you stop finasteride prematurely, the prostate can begin to grow again, and if you stop tamsulosin, your symptoms may return. A healthcare provider will guide your treatment plan.

Common side effects can include dizziness, lightheadedness, and ejaculation disorders from tamsulosin. Finasteride can cause decreased sexual desire, erectile dysfunction, and breast pain. The combination may lead to a higher frequency of these side effects.

Yes, finasteride lowers PSA levels, which can affect prostate cancer screening results. Your doctor will need to know you are taking it to interpret your PSA levels correctly and monitor for any suspicious changes.

No, finasteride should not be handled by women who are pregnant or may become pregnant, as it can cause birth defects in a male fetus. It is also not intended for use in children.

Dosage for tamsulosin and finasteride is determined by a healthcare professional based on individual patient needs, medical history, and the severity of BPH symptoms.

Combination therapy is most beneficial for men with moderate to severe symptoms and a significantly enlarged prostate, as evidenced by large clinical trials. For men with mild symptoms or smaller prostates, monotherapy with an alpha-blocker like tamsulosin may be sufficient.