Hi Customer (name blocked for privacy),
You were put on warfarin to dissolve the blood clot in your leg.It suppose to bring the swelling and redness down ,relieve the pain gradually while dissolving the blood clot.The dark brown spots you are talking about possibly transformation of te bruises to dark spots .People who are on the blood thinner bruises easily.It is also possible that you have chronic venous insufficiency and this dark brown spots so called stasis pigmentation are coming from that condition.Please clic the link below to read more above the blood clot or deep venous thrombosis of the leg.
http://www.nlm.nih.gov/medlineplus/ency/article/000156.htm
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