- Drugs: aspirin, NSAIDs, antibiotics
- Uremia
- Myeloproliferative disorder, eg, polycythemia vera, essential thrombocytosis
- Autoantibody
- Paraproteins, eg, multiple myeloma
- Fibrin degradation products
- von Willebrand’s disease
- Glanzmann’s thrombasthenia
- Bernard-Soulier syndrome
- Storage pool disease, eg, gray platelet syndrome