Prosta-One Drug Interactions

Prostatic volume is correlated with a patient's age whereas serum prostate serum antigen (S-PSA) concentration is correlated with a patient's age and prostatic volume. When S-PSA laboratory determinations are evaluated, consideration should be given to the fact that S-PSA levels decrease in patients treated with Finasteride. S-PSA levels decrease rapidly within the first months of therapy, after which time, S-PSA levels stabilize to a new baseline. The post treatment baseline approximates half of the pre-treatment value. This decrease is predictable over the entire-range of S-PSA values, although it may vary in individual patients. Therefore, in typical patients treated with Finasteride for six months or more S-PSA values should be doubled for comparison to normal ranges in untreated men. There is considerable overlap in S-PSA levels among men with and without prostate cancer. Therefore BHP, S-PSA values within the normal reference range, prostate cancer should not be ruled out regardless of Finasteride treatment. The ability of S-PSA to distinguish between BHP and cancer is not adversely affected by treatment with Finasteride.
Laboratory Test Findings: Consideration should be given to the fact that S-PSA levels are decreased in the patients treated with Finasteride when S-PSA laboratory test determinations are evaluated.
Drug Interactions: No interactions of clinical importance have been identified.
Finasteride does not appear to significantly affect the cytochrome P450-linked drug metabolising enzyme system.
Compounds tested in men included digoxin, propranolol, warfarin, glibenclamide and theophylline and no clinically meaningful interactions were found.
Other Concomitant Therapy: Finasteride has been used concomitantly with ACE-Inhibitors, paracetamol, acetylsalicylic acid, alpha-blockers, cardiac nitrates, diuretics, H₂-antagonist, HMG-CoA reductase Inhibitors, nonsteroidal anti-inflammatory drugs (NSAIDs), quinolones and benzodiazepines without evidence of clinically significant adverse interactions.