tors of CYP2D6, or in patients known to be poor metabolizers of CYP2D6, as there is a potential for significant increase in tamsulosin exposure [see Drug Interactions (7.1), Clinical Pharmacology (12.3)].
Cimetidine: Caution is advised when tamsulosin-containing products, including JALYN, are coadministered with cimetidine [see Drug Interactions (7.1), Clinical Pharmacology (12.3)].
Other Alpha Adrenergic Antagonists: Tamsulosin-containing products, including JALYN, should not be coadministered with other alpha adrenergic antagonists because of the increased risk of symptomatic hypotension.
Phosphodiesterase-5 Inhibitors (PDE-5 Inhibitors): Caution is advised when alpha adrenergic antagonist-containing products, including JALYN, are coadministered with PDE-5 inhibitors. Alpha adrenergic antagonists and PDE-5 inhibitors are both vasodilators that can lower blood pressure. Cocomitant use of these 2 drug classes can potentially cause symptomatic hypotension.
Warfarin: Caution should be exercised with concomitant administration of warfarin and tamsulosin-containing products, including JALYN [see Drug Interactions (7.4), Clinical Pharmacology (12.3)].
5.3 Effects on Prostate-Specific Antigen (PSA) and the Use of PSA in Prostate Cancer Detection
Coadministration of dutasteride with tamsulosin resulted in similar changes to serum PSA as with dutasteride monotherapy.
In clinical studies, dutasteride reduced serum PSA concentration by approximately 50% within 3 to 6months of treatment. This decrease was predictable over the entire range of PSA values in patients with symptomatic BPH, although it may vary in individuals. Dutasteride-containing treatment, including JALYN, may also cause decreases in serum PSA in the presence of prostate cancer. To interpret serial PSAs in men treated with a dutasteride-containing product, including JALYN, a new baseline PSA should be established at least 3months after starting treatment and PSA monitored periodically thereafter. Any confirmed increase from the lowest PSA value while on a dutasteride-containing treatment, including JALYN, may signal the presence of prostate cancer and should be eva luated, even if PSA levels are still within the normal range for men not taking a 5 alpha-reductase inhibitor. Noncompliance with JALYN may also affect PSA test results.
To interpret an isolated PSA value in a man treated with JALYN, for 3months or more, the PSA value should be doubled for comparison with normal values in untreated men.
The free-to-total PSA ratio (percent free PSA) remains constant, even under the influence of dutasteride. If clinicians elect to use percent free PSA as an aid in the detection of prostate cancer in men receiving JALYN, no adjustment to its value appears necessary.
5.4 Increased Risk of High-grade Prostate Cancer
In men aged 50 to 75years with a prior negative biopsy for prostate cancer and a baseline PSA between 2.5ng/mL and 10.0ng/mL taking dutasteride in the 4-year Reduction by Dutasteride of Prostate Cancer Events (REDUCE) trial, there was an increased incidence of Gleason score 8-10 prostate cancer compared with men taking placebo (dutasteride 1.0% versus placebo 0.5%) [see Indications and Usage (1.2), Adverse Reactions (6.1)]. In a 7-year placebo-controlled clinical trial with another 5 alpha-reductase inhibitor (finasteride 5 mg, PROSCAR), similar results for Gleason score 8-10 prostate cancer were observed (finasteride 1.8% versus place |
