It is also sometimes called erythrocytosis, which means too many red blood cells. And it used to be called polycythaemia rubra vera or PCRV. PV is a type of rare blood disorder called a myeloproliferative neoplasm.These are conditions that cause an increase in the number of blood cells.t is also sometimes called erythrocytosis, which means too many red blood cells. And it used to be called polycythaemia rubra vera or PCRV. PV is a type of rare blood disorder called a myeloproliferative neoplasm.
Acetaminophen -- best known as Tylenol in the United States -- does not appear to help ease lower back pain and offers little relief for the most common form of arthritis, according to a new report.
Acetaminophen (Tylenol) liver damage facts. 1  Acetaminophen is a very safe drug when taken as directed, even for people with liver disease. 2  Liver damage from acetaminophen, which can be severe, can result either from an overdose or from regular doses that are taken while drinking alcohol. Most cases of acetaminophen-induced liver injury are caused by an intentional or suicidal overdose.