While a blood clot and a bruise both affect the blood vessels, they are significantly different. Bruises are prominent marks on the skin that vanish over time. Blood clots are a build-up of blood deep inside the tissue or within blood vessels.

Differentiating the causes of a bruise and blood clot

Causes of bruises

Bruises usually form due to trauma such as a bike accident, bone breakage, or intense blow by an object. The injury can burst the blood vessels in the skin and can form anywhere on the skin.

Blood oozes out of the punctured blood vessels, which becomes trapped under the skin surface and forms a bruise. The bruise appears dark blue or black due to the absence of oxygen in the accumulated blood.

Causes of blood clots

Blood clots help heal injuries and are a part of the natural tissue recovery process.

When damage occurs to a body part, it causes platelets to build up near the injury to stop bleeding.

Small blood clots are nothing to worry about, and they resolve on their own. But sometimes, blood clots become excessively large, or they form in places with no injury. Blood clots can self-form inside a blood vessel due to hypercoagulation, for which you should see a doctor.


A blood clot and bruise may have similar symptoms, but some types of clots may cause severe effects.

Symptoms of bruises

For many bruises, the symptoms are very similar. At first, the bruise will have a reddish appearance, and then it may turn purplish within a few hours or days. As the bruise gets better, it will change its shade and get lighter and more yellowish until the color disappears completely.

Bruises can be painful to the touch while healing. As the color lightens and the injury heals, the pain also lessens.

Symptoms of blood clots

There’s no certain pattern that deep tissue blood clots (hematomas) follow when they heal. But they can cause different symptoms depending on their locality. If large hematomas develop within muscles or organs, you should see medical help.

Blood clots that develop inside the blood vessels can hinder the blood and oxygen supply to certain tissue parts. This can cause severe damage to cells, and they may even die. Here are some severe health conditions that thrombus can cause:

  • Stroke
  • Heart attack
  • Mesenteric ischemia
  • Pulmonary embolism
  • Deep vein thrombosis

When to see a doctor

If you’re experiencing severe pain at the injury site, visit a physician for a complete diagnosis. You shouldn’t worry much if you have normal bruising, but abnormal bruising isn’t something to ignore.

Many medical conditions can cause weird bruising and blood clots. And they require proper diagnosis. If it’s been more than 15 days and your bruise isn’t getting better or is accompanied by other symptoms such as pain and inflammation, talk to a doctor.

Schedule an appointment with the experts at EPIC Heart & Vascular Center. Call our Houston location at (832) 432-1951.