Fixed-dose combination: 5-alpha-reductase inhibitor plus selective alpha-1a-adrenoceptor blocker
ATC code: G04CA52 (Tamsulosin and dutasteride)
Dutasteride inhibits both 5-alpha-reductase isoforms (types 1 and 2) – blocks testosterone-to-dihydrotestosterone conversion, the main growth driver of prostatic tissue. Over 6-12 months reduces prostate volume by 20-25%. Tamsulosin selectively blocks alpha-1a adrenoceptors in bladder neck and prostate smooth muscle – rapidly relieves urinary obstruction (effect at 1-2 weeks). The combination provides more complete BPH control and reduces acute urinary retention and surgery risk vs monotherapy (CombAT 2010).
Second line
Benign prostatic hyperplasia in men with moderate-to-severe symptoms (IPSS ≥8), enlarged prostate (≥30 mL), and progression risk. Per EAU 2024 – second-line after alpha-blocker or 5-alpha-reductase inhibitor monotherapy. Dose: 0.5/0.4 mg once daily 30 minutes after a meal. Tamsulosin effect at 1-2 weeks, at 3-6 months. PSA falls by 50% – adjust for this when interpreting results.
Opens the checker prefilled with this drug. Pick the second one from your regimen.
Contraindicated in women at any age. Pregnant women must avoid contact with broken capsules – dutasteride is absorbed through skin and causes hypospadias in male fetuses. In men, dutasteride persists in semen up to 6 months after discontinuation.
Indicated for men only – breastfeeding not applicable.
Reference information, not a clinical decision. Discuss feeding pauses or changes with your physician or an IBCLC.
Dutasteride + Tamsulosin is evaluated for the following indications with varying evidence strength: Benign prostatic hyperplasia (evidence tier A). See the full indication matrix with dosing and citations above on this page.
Common side effects of Dutasteride + Tamsulosin (≥ 1 in 100): Retrograde ejaculation, Erectile dysfunction, Decreased libido, Gynecomastia, Dizziness, Orthostatic hypotension. See the Safety section for uncommon and serious reactions.
FDA category X. Contraindicated in women at any age. Pregnant women must avoid contact with broken capsules – dutasteride is absorbed through skin and causes hypospadias in male fetuses. In men, dutasteride persists in semen up to 6 months after discontinuation.
Indicated for men only – breastfeeding not applicable.
Dutasteride + Tamsulosin is contraindicated in: Hypersensitivity to components or other 5-alpha-reductase inhibitors; Severe orthostatic hypotension history; Severe hepatic impairment; Women and children; Contact of pregnant women with broken capsules (dutasteride teratogenicity). Full list in the Safety section.