Stereochemistry
Warfarin contains a stereocenter and consists of two enantiomers. This is a racemate, i.e., a 1: 1 mixture of ( R ) – and the ( S ) – form:

Pharmacology
Pharmacokinetics
Warfarin consists of a racemic mixture of two active enantiomers—R- and S- forms—each of which is cleared by different pathways. S-warfarin is two to five times more potent than the R-isomer in producing an anticoagulant response. Both the enantiomers of warfarin undergo CYP-mediated metabolism by many different CYPs to form 3,4,6,7,8 and 10-hydroxy warfarin metabolites, major being 7-OH warfarin formed from S-warfarin by CYP2C9 and 10-OH warfarin from R-warfarin by CYP3A4.Warfarin is slower-acting than the common anticoagulant heparin, though it has a number of advantages. Heparin must be given by injection, whereas warfarin is available orally. Warfarin has a long half-life and need only be given once a day. Heparin can also cause a prothrombotic condition, heparin-induced thrombocytopenia (an antibody-mediated decrease in platelet levels), which increases the risk for thrombosis. It takes several days for warfarin to reach the therapeutic effect, since the circulating coagulation factors are not affected by the drug (thrombin has a half-life time of days). Warfarins long half-life means that it remains effective for several days after it is stopped. Furthermore, if given initially without additional anticoagulant cover, it can increase thrombosis risk (see below).
Availability
Flutamide is marketed widely throughout the world, including in the United States, Canada, Europe, Australia, New Zealand, South Africa, Central and South America, East and Southeast Asia, India, and the Middle East. Research
Prostate cancer
The combination of an estrogen and flutamide as a form of combined androgen blockade for the treatment of prostate cancer has been researched. Enlarged prostate
Flutamide has been studied in the treatment of benign prostatic hyperplasia (BPH; enlarged prostate) in men in several clinical studies. It has been found to reduce prostate volume by about 25%, which is comparable to the reduction achieved with the 5α-reductase inhibitor finasteride. Unfortunately, it has been associated with side effects in these studies including gynecomastia and breast tenderness (in about 50% of patients), gastrointestinal disturbances such as nausea, diarrhea, and flatulence, and hepatotoxicity, although sexual function including libido and erectile potency were maintained. Breast cancer
Flutamide was studied for the treatment of advanced breast cancer in two phase II clinical trials but was found to be ineffective. Out of a total of 47 patients, only three short-term responses occurred. However, the patients in the studies were selected irrespective of AR, ER, PR, or HER2 status, which were all unknown. Psychiatric disorders
Flutamide has been studied in the treatment of bulimia nervosa in women.Flutamide was found to be effective in the treatment of obsessive–compulsive disorder (OCD) in men with comorbid Tourettes syndrome in one small randomized controlled trial. Conversely, it was ineffective in patients with OCD in another study.