BRAND NAMES
 MECHANISM OF ACTION
The development and enlargement of the prostate gland is dependent on the potent androgen, dihydrotestosterone (DHT). Testosterone is converted to DHT by the enzyme 5 alpha-reductase, which exists as 2 isoforms, type I and type II. The type II isoenzyme is primarily active in the reproductive tissues, while the type I isoenzyme is also responsible for testosterone conversion in the skin and liver.
Dutasteride is a competitive and specific inhibitor of both type I and type II 5α-reductase isoenzymes, with which it forms a stable enzyme complex. Dissociation from this complex is extremely slow.
Dutasteride use in BPH has resulted in significantly reductions in prostatic volume and PSA level.
Dutasteride/Tamsulosin indicated for the treatment of symptomatic benign prostatic hyperplasia (BPH) in men with an enlarged prostate.
One capsule daily approximately 30 minutes after the same meal each day. Capsule should be swallowed whole.
 DOSAGE FORMS AND STRENGTHS
0.5 mg dutasteride and 0.4 mg tamsulosin hydrochloride
- Pregnancy and women of childbearing potential.
- Pediatric patients. (4)
- Patients with previously demonstrated, clinically significant hypersensitivity (e.g., serious skin reactions, angioedema, urticaria, pruritus, respiratory symptoms) to dutasteride, other 5 alpha-reductase inhibitors or tamsulosin.
 WARNINGS AND PRECAUTIONS
- Orthostatic hypotension and/or syncope can occur. Advise patients of symptoms related to postural hypotension and to avoid situations where injury could result if syncope occurs.
- Do not use Dutasteride/Tamsulosin with other alpha adrenergic antagonists, as this may increase the risk of hypotension.
- Dutasteride/Tamsulosin reduces serum prostate-specific antigen (PSA) concentration by approximately 50%. However, any confirmed increase in PSA while on Dutasteride/Tamsulosin may signal the presence of prostate cancer and should be evaluated, even if those values are still within the normal range for untreated men.
- Do not use Dutasteride/Tamsulosin with strong inhibitors of cytochrome P450 (CYP) 3A4 (e.g., ketoconazole). Use caution in combination with moderate CYP3A4 inhibitors (e.g., erythromycin) or strong (e.g., paroxetine) or moderate CYP2D6 inhibitors, or known poor metabolizers of CYP2D6. Concomitant use with known inhibitors can cause a marked increase in drug exposure.
- Exercise caution with concomitant use of PDE-5 inhibitors, as this may increase the risk of hypotension.
- Drugs that contain dutasteride, including Dutasteride/Tamsulosin , may increase the risk of high-grade prostate cancer.
- Prior to initiating treatment with Dutasteride/Tamsulosin, consideration should be given to other urological conditions that may cause similar symptoms.
- Women who are pregnant or could become pregnant should not handle Dutasteride/Tamsulosin Capsules due to potential risk to a male fetus.
- Advise patients about the possibility and seriousness of priapism.
- Patients should not donate blood until 6 months after their last dose of Dutasteride/Tamsulosin.
- Intraoperative Floppy Iris Syndrome has been observed during cataract surgery after alpha adrenergic antagonist exposure. Advise patients considering cataract surgery to tell their ophthalmologist that they take or have taken Dutasteride/Tamsulosin Capsules.
- Exercise caution with concomitant use of warfarin.
 PREGNANCY AND LACTATION
 SIDE EFFECTS
The most common adverse reactions, reported in ≥1% of subjects treated with coadministered dutasteride and tamsulosin are ejaculation disorders, impotence, decreased libido, dizziness, and breast disorders.
 RELATED LINKS
|Benign Prostatic Hypertrophy|
|5α reductase inhibitors||Dutasteride (Avodart) • Finasteride (Proscar)|
|Alpha 1 antagonists||Alfuzosin (Uroxatral, Xatral) • Doxazosin (Cardura) • Prazosin • Silodosin (Silodyx, Rapaflo) • Tamsulosin (Omnic, Flomax, Secotex) • Terazosin (Hytrin)|
|Phytotherapy||Pygeum africanum • Serenoa repens|
|PDE5 inhibitors||Tadalafil (Cialis)|
|Combination products||Dutasteride/Tamsulosin (Combodart, Jalyn, Duodart)|