Has anyone taken or taking hydroxyurea?

Hi @karla987
I just started taking Hydroxyurea (HU) on April 9. I was also afraid to take it, but since I am diagnosed with Polycythemia Vera (PV), didn’t want to mess around. I have very high RBC counts. I am also taking aspirin and starting a phlebotomy regime. There are some other threads here I have been following about HU side effects, although those folks have different diagnoses. So far, I have none, other than some thirst, which is good for my hydration anyway. Also some fatigue, but that seems to have gone away. It sounds like a lot of people tolerate it very well, although I see some mention of longer term side effects, but not sure what those have been. I don’t know what lupus anticoagulant is (my daughter has lupus, so I will look it up!), but I would ask your doctor to outline your risks/benefits to help you feel more comfortable taking it or look at options. I personally need to get my blood numbers under control to avoid a clot, so have gotten over my anxiety about it for now. Hope all goes well for you.

Hi @ckmrust,
I also have very high RBC counts, along with Polycythemia Vera (PV), ADAMTS13 deficiency, lupus, and Antiphospholipid Syndrome (APS).

I’ve written two summaries—one on Polycythemia Vera (PV) and another on ADAMTS13
deficiency—if you’re interested in reading them.

Medications to Avoid in Blood Disorders: A Focus on ADAMTS13 Deficiency, Erythrocytosis, and Polycythemia Vera https://swaresearch.blogspot.com/2025/10/medications-to-avoid-in-blood-disorders.html
Polycythemia Vera (PV): Causes, Symptoms, Diagnosis, and the Role of JAK2 Mutations https://swaresearch.blogspot.com/2025/02/polycythemia-vera-pv-causes-symptoms.html

@swalex thanks for these links!