Quick answer
The most widely used medications for an enlarged prostate are alpha-blockers, such as tamsulosin, which relieve symptoms within days. Finasteride and dutasteride shrink the prostate over months and are used when the risk of getting worse is higher.1 There are also medications for urgency, and tadalafil. The choice depends on the type of symptom and on the side effects you are willing to accept.1,2
The groups of medications
| Group | How it helps | Side effects most often cited |
|---|---|---|
| Alpha-blockers: tamsulosin, alfuzosin, doxazosin, silodosin | Relax the prostate and relieve symptoms1 | Dizziness, tiredness, drop in blood pressure on standing, changes in ejaculation1 |
| Finasteride and dutasteride | Shrink the prostate by 18% to 28%1 | Lower libido, erectile dysfunction, changes in ejaculation, breast enlargement1 |
| Tadalafil 5 mg | Reduces urinary symptoms slightly1 | Cannot be used with nitrates or in some heart conditions1 |
| Medications for urgency: antimuscarinics and mirabegron | Act on the bladder, when urgency and frequency predominate1 | Antimuscarinics: dry mouth, constipation and caution when urine is left in the bladder. Mirabegron: not used with very high, uncontrolled blood pressure1 |
Alpha-blockers
They are usually the first choice among the medications, because they work quickly and have few serious side effects. They relieve symptoms, but do not prevent urinary retention or the need for surgery.1
Doxazosin has more effect on blood pressure than alfuzosin and tamsulosin. People with heart disease or who take blood pressure medications need closer attention.1 Libido and erections do not usually change, but ejaculation may decrease or disappear while the medication is taken.1
Finasteride and dutasteride
They lower the hormone that acts on the prostate. After two to four years, symptoms improve by about 15% to 30%.1 The effect takes at least six months to appear, and the European guideline recommends them for men at higher risk of getting worse, such as those with a prostate above 40 g.1
Breast enlargement, with or without pain, occurs in 1% to 2% of men. Two studies suggested more aggressive tumors with these medications, without a proven causal link. The European Medicines Agency advises stopping finasteride and seeing a doctor in case of low mood, depression or suicidal thoughts.1
Tadalafil
Tadalafil 5 mg, once a day, is part of the treatment of an enlarged prostate. In a Cochrane review cited by the European guideline, this group of medications lowered the IPSS by about 2 points compared with placebo. Compared with alpha-blockers, there was no difference in the IPSS.1
The side effects cited in the studies include facial flushing, reflux, headache, back pain and a stuffy nose. Tadalafil cannot be used with nitrates or in some heart conditions.1
When to combine
Combining an alpha-blocker with finasteride or dutasteride is recommended for moderate or severe symptoms with a higher risk of getting worse.1
| MTOPS study, 3,047 men | Reduction in the risk of getting worse |
|---|---|
| Finasteride | 34% |
| Doxazosin | 39% |
| Both together | 66% |
The comparison was with placebo, over an average follow-up of 4.5 years.3 The CombAT study, with 4,844 men over four years, also found more benefit on symptoms with tamsulosin and dutasteride together. The side effects of the two medications can add up.1,4
Cataract surgery
Alpha-blockers are linked to a change in the iris during cataract surgery, with a higher risk with tamsulosin. If you are going to have the operation, tell your eye surgeon. The European guideline recommends not starting the medication before a scheduled operation.1
How I approach it
In my practice, I choose the medication based on the symptom that bothers you most and on the size of the prostate. I explain how long it takes to work and what may change in your sexual life before you start. I reassess your symptoms and, if the relief is not enough, we talk about the next steps.
When to see a urologist
- If symptoms continue after the agreed time
- If you have dizziness, a drop in blood pressure or side effects that get in the way
- If your sexual life changes and that bothers you
- If you cannot urinate, contact me the same day
Frequently asked questions
How long does the medication take to work?+
Alpha-blockers can work within hours or days, with the full effect in a few weeks. Finasteride and dutasteride need at least six months.1
Will I have to take it forever?+
It depends on the medication and on your response. In one study, almost three quarters of men did not get worse when they stopped tamsulosin after six months of combination with dutasteride. Do not stop on your own.1
Do finasteride and dutasteride change PSA?+
Yes. They lower PSA by about 50% after 6 to 12 months. Always mention that you take these medications before the test is interpreted.1
Do the medications affect sexual life?+
They can. Alpha-blockers can change ejaculation. Finasteride and dutasteride can reduce libido and cause erectile dysfunction.1
I am having cataract surgery. Do I need to tell anyone?+
Yes. Tell your eye surgeon if you take an alpha-blocker. The European guideline recommends not starting this medication before a scheduled cataract operation.1
References
- EAU Guidelines on the Management of Non-neurogenic Male LUTS. European Association of Urology; 2026. Disease management chapter. EAU
- Goueli R, Badlani GH, Welliver C, et al. Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA Guideline (2026) Part II: Medical Management. J Urol. 2026;216(2):152-160. PubMed
- McConnell JD, Roehrborn CG, Bautista OM, et al. The long-term effect of doxazosin, finasteride, and combination therapy on the clinical progression of benign prostatic hyperplasia. N Engl J Med. 2003;349(25):2387-98. PubMed
- Roehrborn CG, Siami P, Barkin J, et al. The effects of combination therapy with dutasteride and tamsulosin on clinical outcomes in men with symptomatic benign prostatic hyperplasia: 4-year results from the CombAT study. Eur Urol. 2010;57(1):123-31. PubMed
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