Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
JALYN vs DUTASTERIDE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Jalyn is a combination of dutasteride, a 5α-reductase inhibitor that inhibits the conversion of testosterone to dihydrotestosterone (DHT), and tamsulosin, an α1-adrenoceptor antagonist that relaxes smooth muscle in the prostate and bladder neck.
Competitive inhibitor of type II and type I 5α-reductase isoenzymes, blocking conversion of testosterone to dihydrotestosterone (DHT) in prostate, hair follicles, and other tissues.
Treatment of symptomatic benign prostatic hyperplasia (BPH),Reduction in risk of acute urinary retention,Reduction in risk of need for BPH-related surgery
FDA: Treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate,FDA: Reduce risk of acute urinary retention,FDA: Reduce need for BPH-related surgery,Off-label: Male androgenetic alopecia
1 capsule (0.5 mg dutasteride/0.4 mg tamsulosin) orally once daily, 30 minutes after the same meal each day.
0.5 mg orally once daily.
Dutasteride: 5 weeks (t½ ∼3-5 weeks) due to high tissue binding and slow elimination; Tamsulosin: 9-13 hours (t½ ∼9-13 h) in healthy subjects, prolonged in elderly (∼14-15 h).
Terminal half-life approximately 3-4 weeks (21-35 days) in young adults; 5-6 weeks in elderly; supports once-daily dosing due to slow elimination.
Dutasteride is extensively metabolized by CYP3A4 and CYP3A5. Tamsulosin is extensively metabolized by CYP3A4 and CYP2D6.
Extensively metabolized in liver via CYP3A4 and CYP1A2; minor metabolism by CYP2C8, CYP2C9, CYP2C19, and CYP2D6.
Dutasteride: 40% renal, 60% fecal as metabolites; Tamsulosin: 76% renal (9% unchanged), 24% fecal as metabolites.
Primarily fecal (70%) as metabolites; renal excretion accounts for <5% unchanged drug.
Dutasteride: 99.0-99.5% bound to albumin and alpha-1-acid glycoprotein; Tamsulosin: 94-99% bound to alpha-1-acid glycoprotein.
>99% bound to albumin and alpha-1 acid glycoprotein; high affinity.
Dutasteride: 300-500 L (∼3-4 L/kg); Tamsulosin: 16 L (∼0.2 L/kg). Dutasteride’s large Vd indicates extensive tissue distribution.
Approximately 300-500 L (3-5 L/kg), indicating extensive tissue distribution, particularly to prostate and seminal vesicles.
Oral: Dutasteride ∼60% (capsule); Tamsulosin ∼90% (capsule, under fed conditions slightly reduced).
Oral: Approximately 60% (range 40-80%) with food; not administered parenterally.
No dose adjustment required for mild to moderate renal impairment (GFR ≥30 m L/min). Not recommended for severe renal impairment (GFR <30 m L/min) due to lack of data.
No dose adjustment required for renal impairment (including dialysis).
Contraindicated in severe hepatic impairment (Child-Pugh class C). No dose adjustment for mild to moderate impairment (Child-Pugh A or B), but use with caution.
Contraindicated in Child-Pugh Class C; use with caution in mild to moderate impairment (Child-Pugh A/B) with no specific dose adjustment established.
Not indicated for use in pediatric patients. Safety and efficacy not established.
Not indicated in pediatric patients; safety and efficacy not established.
No specific dose adjustment recommended based on age alone. Monitor for orthostatic hypotension, dizziness, and falls risk, especially in elderly patients. Consider underlying renal and hepatic function.
No specific dose adjustment required; monitor for adverse effects (e.g., dizziness, orthostatic hypotension) due to age-related comorbidities.
None.
No FDA black box warning.
Use with caution in combination with other alpha-blockers due to risk of hypotension,Postural hypotension may occur, especially at initiation of therapy,Not recommended for use in women, children, or adolescents due to teratogenic risk,Evaluate for prostate cancer before initiating therapy,Dutasteride may increase risk of high-grade prostate cancer in some studies,Hepatic impairment may alter metabolism of dutasteride
Risk of high-grade prostate cancer in men aged 50-79 with elevated PSA and previous negative biopsy (see PLCO trial),Increased risk of sexual adverse events (impotence, decreased libido, ejaculation disorders) that may persist after discontinuation,Elevated PSA levels: use caution when interpreting PSA values; establish new baseline after 6 months of treatment
Hypersensitivity to dutasteride, tamsulosin, or any component of the formulation,Use in women of childbearing potential,Use in pediatric patients
Women of childbearing potential (pregnancy category X; risk of fetal harm due to inhibition of 5α-reductase),History of hypersensitivity to dutasteride or other 5α-reductase inhibitors,Pediatric patients
Avoid grapefruit juice; may increase tamsulosin exposure and adverse effects. Administer with a meal (same meal consistency daily) to reduce tamsulosin-related adverse events. No other food interactions known.
No clinically significant food interactions. May be taken with or without food. Grapefruit juice does not affect dutasteride levels to a clinically relevant extent.
JALYN (dutasteride/tamsulosin) is contraindicated in pregnancy. Dutasteride is a 5-alpha-reductase inhibitor that can inhibit dihydrotestosterone formation, potentially causing abnormal development of external genitalia in male fetuses. Tamsulosin is an alpha-1 blocker with limited data but potential risks. First trimester: avoid; second and third trimesters: avoid due to theoretical risk.
Dutasteride is contraindicated in pregnancy. It is a 5α-reductase inhibitor that can inhibit the conversion of testosterone to dihydrotestosterone (DHT), potentially causing abnormal development of external genitalia in male fetuses. Risk extends throughout all trimesters due to potential disruption of androgen-mediated development in male fetuses during the first trimester and cumulative effects from drug accumulation in adipose tissue. No adequate human studies exist; animal studies show teratogenicity in male offspring at clinically relevant doses.
JALYN is not indicated for use in women. Dutasteride and tamsulosin are excreted in rat milk but no human data. M/P ratio unknown; avoid breastfeeding due to potential adverse effects in infants.
No data on dutasteride in human milk. M/P ratio unknown. Dutasteride is highly lipophilic and likely excreted in breast milk. Because of potential adverse effects on the nursing infant (e.g., interference with androgen-mediated development in male infants), breastfeeding is contraindicated during therapy and for at least 6 months after the last dose due to long half-life (approximately 5 weeks).
No dose adjustments are applicable because JALYN is contraindicated in pregnancy. Pharmacokinetic changes in pregnancy are irrelevant as the drug should not be used.
No dose adjustment studies in pregnancy because dutasteride is contraindicated. Pharmacokinetic changes in pregnancy (increased volume of distribution, altered metabolism) could affect dutasteride levels, but no adjustments are recommended as drug should not be used. If inadvertently used, discontinue immediately and monitor for adverse effects.
Jalyn is a fixed-dose combination of dutasteride (5α-reductase inhibitor) and tamsulosin (α1-adrenergic antagonist) for symptomatic benign prostatic hyperplasia (BPH). Onset of symptom relief is faster than either agent alone. Tamsulosin component may cause orthostatic hypotension, especially in elderly patients; counsel to rise slowly. Dutasteride reduces serum prostate-specific antigen (PSA) by approximately 50% after 6 months; PSA levels should be interpreted accordingly. Avoid use in women of childbearing potential; dutasteride is teratogenic and can be absorbed through skin contact with capsules.
Monitor PSA levels cautiously, as dutasteride reduces serum PSA by approximately 50% after 6 months; double the PSA value for comparison to untreated men. Do not handle crushed or broken capsules if pregnant or planning pregnancy, as absorption through skin may cause fetal harm. Assess for signs of high-grade prostate cancer before initiating therapy, as dutasteride may increase the risk of Gleason 8-10 tumors. Onset of symptom relief may take 3-6 months; do not discontinue prematurely. Avoid concomitant use with strong CYP3A4 inhibitors (e.g., ritonavir, ketoconazole) as they increase dutasteride exposure.
Take Jalyn 30 minutes after the same meal each day to maintain consistent absorption.,Do not crush, chew, or open capsules; swallow whole.,Avoid grapefruit juice, which may increase tamsulosin levels.,Rise slowly from sitting or lying to prevent dizziness from low blood pressure.,Report symptoms like fainting, severe headache, or prolonged painful erection (priapism) immediately.,Do not donate blood during therapy and for 6 months after stopping due to dutasteride transfer risk.,Use reliable contraception if partner is of childbearing potential; dutasteride can cause fetal harm.
Take exactly as prescribed; do not stop or change dose without consulting your doctor.,Swallow the capsule whole; do not chew or open it.,It may take 3 to 6 months to see improvement in symptoms.,Avoid handling leaking or crushed capsules if you are a woman who is or may become pregnant; wash area immediately with soap and water if skin contact occurs.,Do not donate blood for at least 6 months after your last dose to prevent exposure to a pregnant woman.,Report any breast lumps, pain, or nipple discharge promptly.,You will need regular blood tests for PSA level monitoring; inform your doctor that you are taking dutasteride.,Dutasteride can decrease sperm count and may affect fertility; discuss this with your doctor if planning to father a child.
No interactions on record
"Dutasteride, a 5α-reductase inhibitor, may inhibit cytochrome P450 enzymes, particularly CYP3A4, which is involved in the metabolism of sulfisoxazole. This inhibition can lead to decreased clearance of sulfisoxazole, resulting in elevated plasma concentrations. Increased sulfisoxazole levels may potentiate its adverse effects, including hypersensitivity reactions, crystalluria, and hematologic toxicity such as agranulocytosis."
"Concomitant use of dutasteride, a 5α-reductase inhibitor, with nelfinavir, a protease inhibitor and potent CYP3A4 inhibitor, is predicted to increase the serum concentration of nelfinavir. This occurs because dutasteride may inhibit the metabolism of nelfinavir via competition for CYP3A4, leading to elevated nelfinavir levels and an increased risk of adverse effects such as gastrointestinal disturbances, hepatotoxicity, and metabolic complications. Clinical monitoring for toxicity and dose adjustments are warranted."
"Dutasteride, a 5α-reductase inhibitor, is metabolized primarily by CYP3A4 and to a lesser extent by CYP2D6. Itraconazole is a potent inhibitor of CYP3A4 and also inhibits P-glycoprotein. Coadministration leads to significantly increased serum concentrations of dutasteride, raising the risk of adverse effects such as gynecomastia, sexual dysfunction, and depression. The effect on itraconazole levels is minimal and clinically irrelevant."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about JALYN vs DUTASTERIDE, answered by our medical review team.
JALYN is a 5-Alpha Reductase Inhibitor/Alpha-1 Blocker Combination that works by Jalyn is a combination of dutasteride, a 5α-reductase inhibitor that inhibits the conversion of testosterone to dihydrotestosterone (DHT), and tamsulosin, an α1-adrenoceptor antagonist that relaxes smooth muscle in the prostate and bladder neck.. DUTASTERIDE is a 5-alpha Reductase Inhibitor that works by Competitive inhibitor of type II and type I 5α-reductase isoenzymes, blocking conversion of testosterone to dihydrotestosterone (DHT) in prostate, hair follicles, and other tissues.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between JALYN and DUTASTERIDE depend on the specific clinical indication. These are agents from distinct pharmacological classes and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of JALYN is: 1 capsule (0.5 mg dutasteride/0.4 mg tamsulosin) orally once daily, 30 minutes after the same meal each day.. The standard adult dose of DUTASTERIDE is: 0.5 mg orally once daily.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between JALYN and DUTASTERIDE in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. JALYN is classified as Category C. JALYN (dutasteride/tamsulosin) is contraindicated in pregnancy. Dutasteride is a 5-alpha-reductase inhibitor that can inhibit dihydrotestosterone formation, potentially causing abn. DUTASTERIDE is classified as Category D/X. Dutasteride is contraindicated in pregnancy. It is a 5α-reductase inhibitor that can inhibit the conversion of testosterone to dihydrotestosterone (DHT), potentially causing abnorm. Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.