What Is Dutasteride/Tamsulosin (Jalyn)? Uses, Dosage, and What You Need to Know in 2026

If your doctor has recommended Jalyn or dutasteride/tamsulosin for your enlarged prostate, you may have questions about what exactly this medication is, what it does, and how to take it safely. This guide answers those questions in clear, straightforward terms.

What Is Dutasteride/Tamsulosin (Jalyn)?

Dutasteride/tamsulosin, sold under the brand name Jalyn, is an FDA-approved prescription medication for treating benign prostatic hyperplasia (BPH) — commonly called an enlarged prostate. It was approved by the FDA on June 14, 2010, and is manufactured by GlaxoSmithKline (GSK). Jalyn is unique in that it combines two medications with completely different mechanisms of action into a single daily capsule:

Dutasteride 0.5 mg — a 5-alpha reductase inhibitor (5-ARI) that reduces prostate size by blocking DHT production

Tamsulosin HCl 0.4 mg — an alpha-1A adrenergic receptor blocker that relaxes the muscles around the prostate and bladder neck for faster symptom relief

What Does Dutasteride/Tamsulosin Treat?

Dutasteride/tamsulosin is FDA-approved specifically for the treatment of symptomatic BPH in men with an enlarged prostate. BPH is not cancer — it's a non-cancerous enlargement of the prostate gland that is extremely common as men age. It affects roughly 50% of men over 50 and more than 90% of men over 80.

BPH symptoms include:

Weak or slow urine stream

Difficulty starting urination (hesitancy)

Stopping and starting while urinating

Feeling like your bladder doesn't completely empty

Frequent urination, especially at night (nocturia)

Urgency — a sudden strong need to urinate

Left untreated, severe BPH can lead to acute urinary retention (the sudden inability to urinate), urinary tract infections, bladder damage, or the need for prostate surgery. The CombAT clinical trial showed that dutasteride/tamsulosin combination therapy reduces the risk of acute urinary retention or BPH-related surgery by 66% compared to tamsulosin alone over 4 years.

Dutasteride/Tamsulosin Dosage: How to Take It

The standard dose is:

One capsule (0.5 mg dutasteride / 0.4 mg tamsulosin) once daily, approximately 30 minutes after the same meal each day

Important dosing tips:

Swallow the capsule whole — do not chew, crush, or open it. The contents can irritate your mouth and throat, and dutasteride can be absorbed through mucous membranes.

Take at the same time each day for best results.

If you miss a dose, take it as soon as you remember — unless it's almost time for your next dose. Don't double up.

Store at room temperature (68°F–77°F). Avoid extreme heat — capsules can leak or change shape if stored too hot.

How Long Does It Take to Work?

The two components work on different timelines:

Tamsulosin: Begins working within days to weeks. You may notice improved urine flow and less urgency relatively quickly.

Dutasteride: Takes 3–6 months to meaningfully shrink the prostate. Be patient — most patients notice the full benefit of the dutasteride component after several months of consistent use.

39,333+ patients found their medications in stock

39K+

Find Dutasteride/Tamsulosin In Stock Today →

Who Should NOT Take Dutasteride/Tamsulosin?

Women (especially pregnant women) — dutasteride can harm male fetal development

Children and adolescents

People with severe liver disease (dutasteride is metabolized by the liver)

Those allergic to dutasteride, other 5-alpha reductase inhibitors (finasteride), or tamsulosin

Anyone already taking another alpha-blocker (risk of dangerous low blood pressure)

What About Cost and Finding the Medication?

Generic dutasteride/tamsulosin is generally affordable with coupons — as low as $99–$109 for a 90-day supply via GoodRx. Brand Jalyn is very expensive ($1,900+/month). If you have trouble finding the medication in stock, medfinder can locate pharmacies near you with it in stock. For more on saving money, see our guide on how to save money on dutasteride/tamsulosin in 2026.