Thrombocytosis is an excessive production of platelets by the body, according to Mayo Clinic. It rarely manifests in symptoms and may occur as a result of an underlying condition or bone marrow disorder.
Thrombocytosis that occurs due to an underlying condition is known as reactive thrombocytosis, while thrombocytosis that results from a bone marrow disorder is referred to as essential thrombocythemia, notes Mayo Clinic. Individuals with essential thrombocythemia have higher chances of experiencing blood clots than those with reactive thrombocytosis. Some of the conditions that may cause reactive thrombocytosis include cancer, infections, heart attack, spleen removal and acute bleeding. Medications such as epinephrine, tretinoin and vincristine can also cause reactive thrombocytosis.