Started Hydroxyurea: How long to see decrease in counts?

Hi there,

I was diagnosed with ET last March. My platelets were 1,200. I began taking 1,000 mg Hydroxyurea daily and my platelets went dow to the 300s within 2 weeks.

Since I also have MDS (low blood counts), they reduced me to 500mg a day because it was also lowering WBC and RBC along with Platelets. Also because the 1,000 mg a day did the job very quickly.

I suppose everyone is different and will have different results. My Platelets have been creeping back up (mid 500s), but for now the Hydroxyurea is doing its job.

I have not had any bad side effects from the drug.

Best of luck to you!

Greetings back to you!
Thank you so, so much for your response. It truly helps to hear about others plight/story.
I failed to mention that the 1 side effect I have experienced was thinning hair. Otherwise, nothing drastic.

Thank you again for your well wishes.

Best of luck to you as well!

I was on Hydrea 500 mg 3 x's a week. I told my hematologist of the side effects I was having and he just brushed it off. He said the only side effects he had seen were ulcers on someone's shin and just on 2 people . My hair was thinning...not a side effect per dr. I would have pain in my shins....not a side effect per dr...I finally adjusted to the dosage and thought I was doing ok. Suddenly I had a change in my vision. There were times I would have to wear two pair of reading glasses. I went to my eye dr and after looking in my eyes he told me he thought it was my retina but it was not.. My cornea was swollen, He asked me about new meds since my last visit and I told him about the hydrea, He then asked did I have sores in my mouth and I said yes and then asked was my skin very dry, I said yes I would like to get into a barrel of lotion and soak for a day or too.

I called my hematologist that afternoon and they said I was having allergic reactions and took me off. He called me in anagralide (sp) and on my first one I had a reaction. That was on Saturday and I didn't take any more until Monday, the first one I took was ok but the second one I had the same side effects.

I stopped taking that and I started taking 25 mg of CBD (gummies) and 2 baby aspirin. I don't go back to the hematologist until 4/25. I am thinking seriously of having my PCP check my platelet range before I go back

This is just a guessing game for me. I don't know if I am shooting myself in the foot or not

I don't there is an average time. I have been on HU for 14 months. My platelet count was in the mid 700's at the beginning. It finally came down to 435 last month. I have been taking 3 HU capsules a day with aspirin to get here (more than most it seems). So- obviously not an "average" amount of time or meds.

It takes about a week for the medication to take effect. You may see results at your next blood test, or it may take longer. Everyone of us reacts differently.

How high your dosage is, and what driver mutation you have, may also be factors in how quickly HU brings down your platelet count.

I have ET with JAK2 mutation. It took 22 weeks taking 500mg HU once daily to drop my platelets from 628 to 498. At that point I stopped HU for 3 months because of lethargy, brain fog, and (for the first time in my life) migraines. Platelets were 628 when I started back on HU 500mg 3 times weekly. At my most recent checkup, four months after restarting HU, platelets were 587 which is in the target range set by my hematologist. Lethargy persists, but there's less brain fog if I'm sleeping well and headaches are rare.

For me, the brain fog and lethargy were worse before HU, and ocular migraines went away after I started HU. But I have heard many fellow patients say the trouble started with HU, so I don't doubt it. I am also CALR+, and I wonder if that makes a difference. I wish they would study this.

Brain fog is common with infused chemo for acute cancers. So I wonder if HU, mild as it is, has that effect for some. Again, would be good to know if it's disease or meds.

My doc told me that the lethargy/fatigue are common symptoms of any blood cancer, along with the night sweats. I keep my bedroom cold and exercise to fight the lethargy. Helps.

I had my platelets checked yesterday and they were up 200,000+ so I guess that shows me the CBD does not help. Start Anagrelide last night

Thanks. I've often wondered whether the lethargy and brain fog were more from the ET or the HU. I'd love to see more studies. Thank goodness, I've never experienced night sweats, even during menopause, but I'm a big believer in regular exercise and love a cold bedroom.