| Idiopathic |
| Cytotoxic drugs and radiation |
| Cancer treatment (anticipated effect) |
| Drug reaction |
| Anti-seizure agents: carbamazepine, phenytoin, others |
| Antibiotics: sulfonamides, chloramphenicol |
| Nonsteroidal anti-inflammatory drugs (NSAIDs): phenylbutazone, indomethacin |
| Anti-thyroid medications: methimazole, propylthiouracil |
| Gold |
| Arsenicals |
| Toxic chemicals |
| Benzene |
| Solvents |
| Glue vapors |
| Viral infections |
| Epstein-Barr virus |
| Seronegative (non-A through -G) hepatitis |
| Human immunodeficiency virus (HIV) |
| Other herpes viruses |
| Immune disorders |
| Eosinophilic fasciitis |
| Systemic lupus erythematosus |
| Graft-versus-host disease |
| Miscellaneous |
| Paroxysmal nocturnal hemoglobinuria |
| Thymoma |
| Pregnancy |
| Anorexia nervosa |
