Blood or red colored urine, Cloudy urine with strong odor, Dark colored (brown) urine, Difficulty starting urine stream Dark colored (brown) urine, Premature ejaculation Blood or red colored urine, Dark colored (brown) urine, Frequent urge to urinate, Frequent urination Coumadin is an anticoagulant (blood thinner). Warfarin reduces the formation of blood clots. Coumadin is used to treat or prevent blood clots in veins or arteries, which can reduce the risk of stroke, heart attack, or other serious conditions. Along with its needed effects, warfarin (the active ingredient contained in Coumadin) may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention. Dark urine is deeper in color than urine that is usually straw to yellow in color. Darker urine can be different colors, but is usually brown, deep yellow, or maroon. Urine is produced in the. The information reflected here is dependent upon the correct functioning of our algorithm. From time-to-time, our system might experience bugs or glitches that affect the accuracy or correct application of mathematical algorithms. If you've been prescribed warfarin (Coumadin, Jantoven) to prevent blood clots, you probably already know that this powerful drug can save your life if you are at risk of or previously had blood clots. But you may not realize how serious warfarin side effects can be. I have been on 5 mg of Coumadin/Warfarin for at least 10 years. My INR is almost always in the target range 2.0 to 3.0. I never see any blood in urine, or elsewhere. Warfarin is used to prevent blood clots from forming or growing larger in your blood and blood vessels. It is prescribed for people with certain types of irregular heartbeat, people with prosthetic (replacement or mechanical) heart valves, and people who have suffered a heart attack. Most car rental companies offer unlimited mileage in metropolitan areas, including all major capital cities (with an exception of Northern Territory) and some tourist destinations. Abnormal urine color may be caused by infection, disease, medicines, or food you eat. Cloudy or milky urine is a sign of a urinary tract infection, which may also cause a bad smell. Milky urine may also be caused by bacteria, crystals, fat, white or red blood cells, or mucus in the urine. Dark brown.