Is it common for platelet level to drop?

Counts vary from day to day, but that is a significant drop.

Hoping you will continue to see good results!

Platelets in "normal people" fluctuate a lot. So do ours, just at higher-than-normal levels. In my own experience before going on HU, drops and spikes could be as much as 100 points. Docs are looking at cumulative upward trend, which can be gradual or steep in ET. Your drop might indicate that your trend might be more gradual.

A good question to ask your doc at next visit is how he makes the decision to start platelet reduction therapy.

FWIW, I've been on HU for 6 years, and my lowest reading was 423 and my highest 537, with all other blood counts normal. My hemo calls that "very stable."

How are you feeling?

I feel very normal …always have. I was diagnosed April 2025,

Hi @panamsandy ,
I was found to have high platelets on routine lab work after routine physical December 2025 and told I had ET January 2025. I asked for bone marrow biopsy and on just the day of my bone marrow biopsy only, my platelets dropped 400 mysteriously with me taking nothing. Then I was told I had myelofibrosis. I only started taking low dose aspirin after O/H decided I could in February 2025. I have never taken Hydrea. Also, I have not any Rx med in about thirty years. I have had three labs since February and my platelets went back up. I take just low dose aspirin as I do have elevated platelets. I feel just fine also like you. My BP is normal as well and I take it just about daily each morning per my primary docs’ instructions. He said stress can elevate platelets. I just do not think such large number fluctuations like mine are in platelets is normal though. Your decrease is a reasonable amount. Be happy and enjoy your life.

Was that first reading of 552 similar to previous levels? If not, maybe the second reading was more normal for you. I get monthly blood tests for my Polycythemia and I noticed that even a moderate change in your hydration at the time of the test can have a pretty significant impact on your platelet count.

After my shingles shot, a week later I had my routine quarterly blood chem for ET Jak2 on hydroxyurea plus baby aspirin. And my platelets dropped significantly. So they had me coming back after few weeks. Slowly over maybe 3 months my platelets returned to "normal" in 400s. Apparently based on research the shingrix vaccine can do this, but no worries it returns to normal. To see research use Google scholar.

In 7/2019 it was 227 and every year it slowly went up. 9/2020 260; 6/2021 322; 9/2023 365, 10/2024 423, 12/2024 420, 4/2025 552 and the most recent 7/2025 462. I began baby aspirin 4/2025.