Platelet dysfunction may be due to a problem in the platelets themselves or to an external factor that alters the function of normal platelets.
Dysfunction may be hereditary or acquired. Von Willebrand disease (see see Von Willebrand Disease) is the most common hereditary platelet disorder.
Acquired platelet disorders are usually caused by drugs or certain diseases. The most common drugs that affect platelet function are aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs), along with drugs such as clopidogrel and similar drugs that are used to prevent strokes and heart attacks. Diseases that can affect platelet function include cirrhosis, multiple myeloma, and systemic lupus erythematosus (lupus).
People with hereditary disorders of platelet dysfunction may have a lifelong history of easy bruising or excessive bleeding after minor injuries or minor surgery such as dental extractions. Women may have a history of very heavy menstrual periods. Other symptoms of platelet disorders include tiny red dots on the skin and bruising after minor injuries.
Doctors suspect a drug is causing platelet dysfunction cause if symptoms begin after a person starts taking a drug that may cause platelet disorders.
Doctors may need to do blood tests to measure substances that are involved in platelet activation and clotting.
If platelet dysfunction is caused by a drug, stopping the drug usually is the only treatment needed. When people with an inherited platelet dysfuntion have serious bleeding, they may need a platelet transfusion.
Last full review/revision December 2012 by David J. Kuter, MD, DPhil