Sodium phosphonate is available as eye drops and injectable solutions. The function of ophthalmic solution of sodium phosphonate is to treat herpes simplex virus keratitis in which acyclovir is not effective. It inhibits the replication of cytomegalovirus, herpes simplex virus and other herpes viruses. Sodium phosphophosphonate injection is mainly used for the treatment of cytomegalovirus retinitis in immunodeficient persons, such as AIDS patients. The side effects of sodium phosphonate are significant and can damage kidney function, central nervous system, blood system, and cardiovascular system. It also causes nausea, vomiting, abdominal pain, fever, and abnormal liver function.