For people with ET who are low-risk, aspirin and monitor is the standard treatment approach. You would be considered low-risk ET at age 47, PLT in 800s, with no history of thrombosis or hemorrhage , and no co-occurring medical risk factors (e.g., cardiovascular issues). Usually, the only reason to consider other medications for low-risk ET would be if there were secondary symptoms that required intervention (e.g., pruritis). .

It is worth noting that there is no linear correlation between absolute number of platelets and thrombosis risk. There is an increased risk of hemorrhage as platelet levels go higher. Very high platelet levels carry a risk of Acquired von Willebrand Disease, a bleeding disorder.

It is worth noting that when the time comes to consider cytoreductive treatment, there are more options than hydroxyurea. The interferons (e.g., Pegasys) are also recognized as a preferred treatment option. By the time you would need cytoreductive treatment, there will likely be more medication options as there are some promising drugs in clinical trials.

Wishing you all the best.

Not everyone has an adverse effect to Hydroxyeurea- I took it for 23 years with no adverse effects except in the last year the purities was very uncomfortable when I bathed. I was on this medicine plus asprin for a long time and never had a day off sick from work!

Hi Renee - that applies to me, platelets are in your range, I’m 43y, and on daily aspirin only. Concur with all of the other comments as well and my Dr has noted the same. My Dr said it is also hit or miss whether people respond to two aspirin daily - it doesn’t necessarily work for me for instance. That could be due to when I am taking them, what I am doing, but going to be experimenting with this too.

Hi Renee - I have ET, JAK2 V617F, and I'm 58. My platelet counts are usually between 600 and 650. I only take low-dose aspirin because I'm low risk, although I plan on starting interferon alpha in the next few months in an attempt to reduce the other long term complications from ET besides clotting. There is evidence to suggest that it can. Increased platelet counts don't put you at higher risk of clotting. When counts reach 1 to 1.5 million, then there is an increased risk of bleeding and it would be important to lower counts. At your age, if there is no history of clotting or other cardiovascular risk factors, then aspirin only is appropriate according to NCCN guidelines. Lowering platelet counts to decrease symptoms is another reason why cytoreductive therapy might be started.

Hi Renee.
There are three widely accepted risk factors in ET: age (60 or above); a history of thrombosis; and extremely high platelets. A patient's particular risk assessment is a huge part of treatment decisions.
In my case, since since I was at the threshold of turning 60, with platelet counts over 1 million, my doctor and I decided to start cytoreductive treatment with hydroxyurea. (I've been off it for a year and a half, taking 81 mg aspirin only; my platelets remain high -- my age, too! -- but my thrombotic risk is mitigated by my particular mutation, CALR. I get monthly CBCs and my doctors are watchful.)
Your case is different, Renee, You have none of the three risk factors, and that puts you at low risk.
If you're interested, here's an excerpt from a scholarly article that lays it out in greater detail. The article is from ASH (the American Society of Hematology), which is a reliable source. There are "3 prognostic scoring systems that have been developed for patients with ET. According to the European LeukemiaNet recommendations, age ≥60 years, history of vascular complications, and extreme thrombocytosis are the 3 risk factors used to classify patients with ET at low and high risk of vascular complications in order to decide a cytoreductive treatment." Under those recommendations, you are at low risk if "age <60 y AND no history of thrombosis or major bleeding AND PLT count <1500 × 109/L [1.5 million], that is, none of the 3 major risk factors." The full article is at https://ashpublications.org/blood/article/129/6....
It seems to me that your team has your treatment plan well in hand.
Good luck!

Diagnosis, risk stratification, and response evaluation in classical myeloproliferative neoplasms

https://ashpublications.org/blood/article/129/6/680/36332/Diagnosis-risk-stratification-and-response