Aspirin, or acetylsalicylic acid (ASA), is a very common oral medication used to treat pain, fever, or inflammation. It is available without a prescription. Aspirin is a very old drug. It was originally used in the form of willow tree leaves and has been used as a medicine for more than 2000 years. It was chemically synthesized in 1853. So, it’s been around for a long time. Similar to other nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin also suppresses platelet functioning. Aspirin reduces pain and inflammation and blocks platelet function by inhibiting the production of certain chemicals (called prostaglandins and thromboxanes) produced by the body. In platelets, aspirin irreversibly blocks an enzyme called cyclooxygenase that is used to produce thromboxane A2. Thromboxane production in platelets is important for platelets to contribute to blood clots. So, aspirin helps reduce the ability of platelets to clump together (aggregate) and form blood clots.  

Low dose aspirin (81 to 100 mg per day) has proven to be very effective in reducing the risk of abnormal blood clots in many clinical situations. Aspirin reduces the risk of heart attack or stroke in patients who have already had a one of these cardiovascular events. In a large clinical trial, low dose aspirin was found to reduce the risk of abnormal blood clots in patients with polycythemia vera (PV). Because all of the classical Ph-neg MPNs (PV, ET and MF) are known to be associated with some degree of excess clotting risk, and because the risks for this clotting risk are thought to be shared, aspirin is generally recommended for virtually all patients with these MPNs. 

Side Effects

Common side effects:

  • Upset stomach or stomach irritation
  • Nausea and vomiting
  • Heartburn
  • Stomach cramps

Rare serious side effects:

  • Anemia
  • Bleeding
  • Ulcers
  • Allergic reactions

Additional Information:

Richard T. Silver MD Myeloproliferative Neoplasms Center 525 East 70th St., Starr Pavillion, 3rd Floor New York, NY 10021