Thrombocytopenia is the medical term for a low blood platelet count. Platelets (thrombocytes) are colorless blood cells that play an important role in blood clotting. Platelets stop blood loss by clumping and forming plugs in blood vessel holes.

Thrombocytopenia often occurs as a result of a separate disorder, such as leukemia or an immune system problem, or as a medication side effect. Thrombocytopenia may be mild and cause few signs or symptoms. In rare cases, the number of platelets may be so low that dangerous internal bleeding can occur.

Thrombocytopenia usually improves when the underlying cause is treated. Sometimes medications, surgery or a blood transfusion can help treat chronic thrombocytopenia.


Thrombocytopenia symptoms may include:

  • Prolonged bleeding from cuts
  • Easy or excessive bruising
  • Superficial bleeding into the skin that appears as a rash of pinpoint-sized reddish-purple spots, usually on the lower legs
  • Spontaneous bleeding from the gums or nose
  • Blood in urine or stools
  • Unusually heavy menstrual flows
  • Profuse bleeding during surgery or after dental work


If for any reason the blood platelet count falls below normal, the condition is called thrombocytopenia. Normally, the humans have from 150,000 to 450,000 platelets per microliter of circulating blood. Because each platelet lives only about 10 days, the body continually renews the platelet supply by producing new platelets in the bone marrow.

Thrombocytopenia has many possible causes like trapping of platelets in the spleen, reduced production of platelets or increased breakdown of platelets.

A number of conditions can cause the body to use up or destroy platelets more rapidly than they are produced, leading to a shortage of platelets in the bloodstream. Examples include pregnancy and idiopathic thrombocytopenic purpura (ITP). In ITP, the body's immune system mistakenly identifies platelets as a threat and forms antibodies that attack them. Other conditions include the following:

  • Autoimmune diseases
  • Bacteria in the blood
  • Thrombotic thrombocytopenic purpura (TTP)
  • Hemolytic uremic syndrome
  • Medications

Risk Factors

These include people who:

  • Have some types of cancer, aplastic anemia, or autoimmune diseases
  • Are exposed to certain toxic chemicals
  • Have a reaction to certain medicines
  • Have some viruses
  • Have some genetic conditions
  • People who drink heavily
  • Pregnant women


Dangerous internal bleeding can occur when the platelet count falls below 10,000 platelets per microliter. Though rare, severe thrombocytopenia can cause bleeding into the brain or intestines, which can be fatal.


Whether you can prevent thrombocytopenia depends on its specific cause. Usually the condition cannot be prevented. However, you can take steps to prevent health problems associated with thrombocytopenia. For example:

  • Avoid heavy drinking. Alcohol slows the production of platelets.
  • Try to avoid contact with toxic chemicals. Chemicals such as pesticides, arsenic, and benzene can slow the production of platelets.
  • Avoid medicines that you know have decreased the platelet count in the past.Be aware of medicines that may affect the platelets and raise the risk of bleeding. Get vaccinated for viruses that can affect the platelets.