Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
ADCIRCA vs DUTASTERIDE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Phosphodiesterase-5 (PDE5) inhibitor; increases c GMP in pulmonary vascular smooth muscle, leading to vasodilation.
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 pulmonary arterial hypertension (PAH) (WHO Group I) to improve exercise capacity and delay clinical worsening.,Off-label: Erectile dysfunction (not FDA-approved for this indication in the context of PAH).
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
10 mg orally three times daily.
0.5 mg orally once daily.
Terminal half-life: 10–15 hours in healthy adults; prolonged in hepatic impairment (Child-Pugh B/C: up to 30 hours); clinical context: supports twice-daily dosing
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.
Primarily metabolized by CYP3A4 (major) and CYP2C9 (minor) hepatic enzymes.
Extensively metabolized in liver via CYP3A4 and CYP1A2; minor metabolism by CYP2C8, CYP2C9, CYP2C19, and CYP2D6.
Renal: ~70% (metabolites and unchanged drug), Fecal: ~20%, Biliary: minor
Primarily fecal (70%) as metabolites; renal excretion accounts for <5% unchanged drug.
96% bound to albumin and alpha-1-acid glycoprotein
>99% bound to albumin and alpha-1 acid glycoprotein; high affinity.
Vd: 0.4–0.7 L/kg; suggests distribution into total body water and moderate tissue binding
Approximately 300-500 L (3-5 L/kg), indicating extensive tissue distribution, particularly to prostate and seminal vesicles.
Oral: 80%; absolute bioavailability: 50% due to first-pass metabolism
Oral: Approximately 60% (range 40-80%) with food; not administered parenterally.
No dose adjustment required for mild to moderate renal impairment; avoid use in severe impairment (Cr Cl <30 m L/min) due to lack of data.
No dose adjustment required for renal impairment (including dialysis).
Mild to moderate hepatic impairment (Child-Pugh A or B): 10 mg orally once daily; severe hepatic impairment (Child-Pugh C): contraindicated.
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 established for patients <18 years.
Not indicated in pediatric patients; safety and efficacy not established.
No specific dose adjustment, but caution due to increased sensitivity; monitor renal function.
No specific dose adjustment required; monitor for adverse effects (e.g., dizziness, orthostatic hypotension) due to age-related comorbidities.
Do not use in patients taking nitrates (regularly or intermittently) due to risk of severe hypotension.
No FDA black box warning.
Risk of hypotension, especially with nitrates or alpha-blockers.,Hematologic effects: increased risk of bleeding due to antiplatelet activity; caution with bleeding disorders or anticoagulants.,Vision loss: non-arteritic anterior ischemic optic neuropathy (NAION) has been reported; discontinue if sudden vision loss occurs.,Hearing loss: sudden decrease or loss of hearing; may be accompanied by tinnitus or dizziness.,Use caution in patients with left ventricular outflow obstruction (e.g., aortic stenosis) or severely impaired autonomic control of blood pressure.,Dose adjustment required with strong CYP3A4 inhibitors (e.g., ketoconazole, ritonavir).
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
Concomitant use of nitrates (any form) or nitric oxide donors.,Concomitant use with riociguat or other guanylate cyclase stimulators.,Known hypersensitivity to tadalafil or any component of the product.,Severe hepatic impairment (Child-Pugh class C).
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 and grapefruit juice as they may increase tadalafil levels and risk of side effects. No other significant food interactions. High-fat meals may delay absorption but do not require dose adjustment.
No clinically significant food interactions. May be taken with or without food. Grapefruit juice does not affect dutasteride levels to a clinically relevant extent.
Pregnancy Category B. Animal studies have not demonstrated fetal risk, but there are no adequate and well-controlled studies in pregnant women. First trimester: risk cannot be ruled out; use only if clearly needed. Second and third trimesters: no known fetal risks, but caution advised due to maternal hypotension 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.
Not recommended. Excretion in human milk unknown. M/P ratio not established. Risk of hypotension in neonate. Alternative feeding method advised during therapy and for 48 hours after last dose.
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 specific pharmacokinetic data in pregnancy. Standard dose (40 mg orally once daily) recommended. Monitor for hypotension; dose adjustment not routinely required unless maternal hypotension develops.
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.
Adcirca (tadalafil) is a PDE5 inhibitor indicated for pulmonary arterial hypertension (PAH) to improve exercise ability. It is dosed at 40 mg once daily, not as needed. Avoid use with nitrates due to risk of severe hypotension. Monitor for vision loss (non-arteritic anterior ischemic optic neuropathy) and hearing loss. Use caution in patients with hepatic impairment (Child-Pugh class B: reduce dose; class C: contraindicated). Dose adjustment required with potent CYP3A4 inhibitors (e.g., ketoconazole: reduce to 20 mg). Not recommended for severe renal impairment (Cr Cl <30 m L/min) or on hemodialysis.
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 Adcirca exactly as prescribed, 40 mg once daily, at the same time each day. Do not take it as needed for erectile dysfunction.,Do not take Adcirca if you are taking any form of nitrate medication (e.g., nitroglycerin) or recreational drugs called 'poppers' (amyl nitrate) as this can cause a sudden dangerous drop in blood pressure.,Seek immediate medical attention if you experience sudden vision loss or decrease in hearing, as these may be signs of a serious side effect.,Avoid drinking large amounts of alcohol (e.g., 3 or more drinks) within a short time while taking Adcirca, as it may increase the risk of dizziness, lightheadedness, and fainting.,Inform your healthcare provider about all medications you take, including prescription, over-the-counter, and herbal products, especially alpha-blockers, erythromycin, or ritonavir.,Adcirca may cause dizziness. Do not drive or operate machinery until you know how the medicine affects you.
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 ADCIRCA vs DUTASTERIDE, answered by our medical review team.
ADCIRCA is a PDE5 Inhibitor that works by Phosphodiesterase-5 (PDE5) inhibitor; increases c GMP in pulmonary vascular smooth muscle, leading to vasodilation.. 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 ADCIRCA 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 ADCIRCA is: 10 mg orally three times daily.. 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 ADCIRCA 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. ADCIRCA is classified as Category C. Pregnancy Category B. Animal studies have not demonstrated fetal risk, but there are no adequate and well-controlled studies in pregnant women. First trimester: risk cannot be rule. 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.