Overview of polycythemia vera
Polycythemia vera (PV) is a long-term condition and a type of blood cancer, but it is treatable.
Prevalence of PV in the US
The number of people living with PV in the US in 2026 is estimated to be 90,522, with higher rates reported in men than women.
In PV, the bone marrow produces too many red blood cells, which are the cells that carry oxygen throughout your body.
Too many red blood cells in your blood raises your hematocrit (HCT, the percentage of red blood cells in your blood) to above 45%. This makes your blood thicker.
Controlled HCT means that it is consistently kept below the 45% threshold.
The thicker blood caused by raised HCT levels can increase your risk of blood clots, heart problems, and stroke.
When your blood is thicker, it flows more slowly through your body, along with oxygen that it carries. This can make you feel more tired and out of breath.
Feeling tired or confused (also called brain fog) from low iron is frustrating
But did you know that iron levels can impact red blood cells, increasing the risk of blood clots?
Tell your doctor about what you are feeling and find out what that means for your health.
Managing PV includes understanding your lab results and more—it’s about how you’re functioning, coping, and living. You know best how PV affects your daily life. Learn more about how you can communicate this with your doctor.