How the interaction occurs:
The cause of the interaction is not known. When these two medicines are taken together, the steroid may increase the effects of the blood-thinner.
What might happen:
You may experience an increased chance for bleeding including bleeding from your gums, nosebleeds, unusual bruising, or dark stools.
What you should do about this interaction:
Contact your healthcare professionals (e.g. doctor or pharmacist) as soon as possible about taking these two medicines together. They may already be aware of this interaction and may be monitoring you for it. If your doctor prescribes these medicines together, you may need to check your bleeding times more often. Do not start, stop, or change the dosage of any medicine before checking with them first.
1.Schrogie JJ, Solomon HM. The anticoagulant response to bishydroxycoumarin. II. The effect of D- thyroxine, clofibrate, and norethandrolone. Clin Pharmacol Ther 1967 Jan-Feb;8(1):70-7.
2.Koch-Weser J, Sellers EM. Drug interactions with coumarin anticoagulants (First of two parts). N Engl J Med 1971 Aug 26;285(9):487-98.
3.Husted S, Andreasen F, Foged L. Increased sensitivity to phenprocoumon during methyltestosterone therapy. Eur J Clin Pharmacol 1976;10:209-16.
4.Pyorala K, Kekki M. Decreased anticoagulant tolerance during methandrostenolone therapy. Scand J Clin Lab Invest 1963;15:367-74.
5.Pyorala K, Kekki M. Anabolic steroids and anticoagulant requirements. Lancet 1963 Aug 17;10:360-1.
6.Murakami M, Odake K, Matsuda T, Onchi K, Umeda T, Nishino T. Effects of anabolic steroids on anticoagulants requirements. Jpn Circ J 1965 Mar; 29:243-50.
7.Pyorala K, Myllyla G, Kekki M. Metabolism of warfarin during methandrostenolone treatment. Ann Med Exp Fenn 1965;43:95-7.
8.Dresdale FC, Hayes JC. Potential dangers in the combined use of methandrostenolone and sodium warfarin. J Med Soc N J 1967 Nov; 64(11):609-12.
9.Vere DW, Fearnley GR. Suspected interaction between phenindione and ethyloestrenol. Lancet 1968 Aug 3;2(7562):281.
10.Edwards MS, Curtis JR. Decreased anticoagulant tolerance with oxymetholone. Lancet 1971 Jul 24;2(7717):221.
11.Robinson BH, Hawkins JB, Ellis JE, Moore-Robinson M. Decreased anticoagulant tolerance with oxymetholone. Lancet 1971 Jun 26; 1(7713):1356.
12.De Oya JC, Del Rio A, Noya M, Villanueva A. Decreased anticoagulant tolerance with oxymetholone in paroxysmal nocturnal haemoglobinuria. Lancet 1971 Jul 31;2(7718):259.
13.Ekert H, Muntz RH, Colebatch JH. Decreased anticoagulant tolerance with oxymetholone. Lancet 1971 Sep 11;2(7724):609-10.
14.Longridge RG, Gillam PM, Barton GM. Decreased anticoagulant tolerance with oxymetholone. Lancet 1971 Jul 10;2(7715):90.
15.Goulbourne IA, Macleod DA. An interaction between danazol and warfarin. Case report. Br J Obstet Gynaecol 1981 Sep;88(9):950-1.
16.Small M, Peterkin M, Lowe GD, McCune G, Thomson JA. Danazol and oral anticoagulants. Scott Med J 1982 Oct;27(4):331-2.
17.Acomb C, Shaw PW. A significant interaction between warfarin and stanozolol. Pharm J 1985 Jan 19;234(1):73-4.
18.Lorentz SM, Weibert RT. Potentiation of warfarin anticoagulation by topical testosterone ointment. Clin Pharm 1985 May-Jun;4(3):332-4.
19.Meeks ML, Mahaffey KW, Katz MD. Danazol increases the anticoagulant effect of warfarin. Ann Pharmacother 1992 May;26(5):641-2.
20.Manoharan A, Hewitt B. Danazol therapy in familial antithrombin III deficiency. Clin Lab Haematol 1990;12(3):357-9.
21.Shaw PW, Smith AM. Possible interaction of warfarin and stanozolol. Clin Pharm 1987 Jun;6(6):500-2.
22.Oxandrin (oxandrolone) US prescribing information. Savient Pharmaceuticals, Inc. May 20, 2005.