Hello I am having spontaneous black and blue marks popping out on my body. First it was my legs and now they are appearing on my upper arms. I am on Plavix and aspirin therapy after a heart attack. The spots (marks) on your hands and arms are actually bruises. Being on a blood thinner makes you more sensitive to bruising. Just the slightest little bump will cause you to bruise. Plavix is saving my life every day, day after day. Bruising is a small price to pay for this peace of mind. Bruising is a small price to pay for this peace of mind. Recently, I noticed two penny-sized symmetrical bruises, identical, just under my ribcage. Additionally, he has a huge black and blue mark across his abdomen. Over time he has developed many black and blue marks on his legs and arms. The surgical team at the hospital has taken him off Plavix and is infusing him with blood and fluids. This is not life threatening, but I do think it points to some of the hazards of using a powerful drug like this for a very extended time. I'm sure Big. Bruises in elderly people frequently occur because their skin has become thinner with age. The tissues that support the underlying blood vessels have become more fragile. black blue marks from coumadin Hematoma Overview: Bruises and Blood Spots Under the Skin Multiple leg bruises or black and blue marks on both. - JustAnswer Hematoma Overview: Bruises and Blood Spots Under the Skin Coumadin Drug and Medication User Reviews on RxList PACKAGE INSERT DRAFT Heart Disease, Warfarin (Coumadin), and Other Blood Thinners Plavix discussions (experiences, side effects. Black and blue marks are often associated with bruises. A bruise, or contusion, appears on the skin due to trauma. Examples of trauma are a cut or a blow to an area of the body. If the black and blue marks are occurring more often, are more widespread (even if they have previously been worked up), are always located in the same place, or just don't go away. 3. My husband takes plavix as well as lasinapril, aspirin, etc and i can say YES he dose bruise very easy. Unfortunately I do not know which of these meds cause the bruising. I had two coated stents inserted March 22, 2010 and have been taking plavix, 81 mg aspirin and continue taking coumadin (5mg 6 days and 6 mgs 1 day a week).