Merck Manual

Please confirm that you are not located inside the Russian Federation

honeypot link

Disseminated Intravascular Coagulation (DIC)


Michael B. Streiff

, MD, Johns Hopkins University School of Medicine

Reviewed/Revised Sep 2023
Topic Resources

Disseminated intravascular coagulation is a condition in which small blood clots develop throughout the bloodstream, blocking small blood vessels. The increased clotting depletes the platelets and clotting factors needed to control bleeding, causing excessive bleeding.

  • There are a number of possible causes, including infection, surgery, and complications of childbirth.

  • Excessive clotting is followed by excessive bleeding.

  • The amount of clotting factors in the blood is measured.

  • The underlying disorder is treated.

Disseminated intravascular coagulation (DIC) begins with excessive clotting How Blood Clots Hemostasis is the body's way of stopping injured blood vessels from bleeding. Hemostasis includes clotting of the blood. Too little clotting can cause excessive bleeding from minor injury Too... read more . The excessive clotting is usually stimulated by a substance that enters the blood as part of a disease (such as an infection or certain cancers) or as a complication of childbirth, retention of a dead fetus, or surgery. People who have a severe head injury or who have tissue damage caused by shock Shock Shock is a life-threatening condition in which blood flow to the organs is low, decreasing delivery of oxygen and thus causing organ damage and sometimes death. Blood pressure is usually low... read more , burns Burns Burns are injuries to tissue that result from heat, electricity, radiation, or chemicals. Burns cause varying degrees of pain, blisters, swelling, and skin loss. Small, shallow burns may need... read more Burns , frostbite Frostbite Frostbite is a cold injury in which an area of the body is frozen. Extreme cold may freeze tissues, destroying them and sometimes the surrounding tissues. The area may be numb, white, swollen... read more Frostbite , other injuries, or even a bite by a poisonous snake Snakebites Venomous snakes in the United States include pit vipers (rattlesnakes, copperheads, and cottonmouths) and coral snakes. Severe envenomation can cause damage to the bitten extremity, bleeding... read more Snakebites are also at risk.

As the clotting factors and platelets Blood Clots: Plugging the Breaks Blood Clots: Plugging the Breaks (cell fragments that circulate in the bloodstream and help blood clot) are depleted, excessive bleeding occurs.

DIC may develop

  • Suddenly

  • Slowly

DIC that develops slowly typically results from cancer, aneurysms, or cavernous hemangiomas (collections of dilated blood vessels).

Symptoms of DIC

DIC that develops suddenly usually causes bleeding, which may be severe. If the condition follows surgery or childbirth, bleeding may be uncontrollable. Bleeding may occur at the site of an intravenous injection or in the brain, digestive tract, skin, muscles, or cavities of the body.

If DIC develops more slowly, as in people with cancer, then clots in the veins (deep venous thrombosis Deep Vein Thrombosis (DVT) Deep vein thrombosis is the formation of blood clots (thrombi) in the deep veins, usually in the legs. Blood clots may form in veins if the vein is injured, a disorder causes the blood to clot... read more Deep Vein Thrombosis (DVT) ) are more common than bleeding. If clots form in veins (usually in the legs), the person may have swelling, redness, or pain in the area. However, sometimes no symptoms develop. A clot that forms in a vein may break free and travel (becoming an embolus) to the lungs. Clots in the lungs Pulmonary Embolism (PE) Pulmonary embolism is the blocking of an artery of the lung (pulmonary artery) by a collection of solid material brought through the bloodstream (embolus)—usually a blood clot (thrombus) or... read more may make people short of breath.

Diagnosis of DIC

  • Blood tests

Blood Tests Used to Diagnose DIC

Blood tests may show that the number of platelets in a blood sample has dropped (platelets are used up when blood clots) and that the blood is taking a long time to clot.

The diagnosis of DIC is confirmed if test results show abnormally increased quantities of plasma D-dimer (a substance that blood clots release when they break down. More D-dimer indicates that more clots are being produced than usual) and often a low or decreasing level of fibrinogen (a protein that is consumed when blood clots).

Treatment of DIC

  • Treatment of the underlying disorder

The underlying disorder must be identified and corrected, whether it is an obstetric problem, an infection, or a cancer. The clotting problems subside when the cause is corrected.

DIC that develops suddenly is life threatening and is treated as an emergency. Platelets and clotting factors are transfused to replace those depleted and to stop bleeding.

Heparin may be used to slow the clotting in people who have more chronic, milder DIC in whom clotting is more of a problem than bleeding.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Hepflush-10 , Hep-Lock, Hep-Lock U/P, Monoject Prefill Advanced Heparin Lock Flush, SASH Normal Saline and Heparin
quiz link

Test your knowledge

Take a Quiz!