Muscle pain since starting HU

[Digger031145]

I started taking HU in Feb 2015.

In March 2015 I started getting muscle pain in my mid to upper back on one side.

Since then I have more muscle pain than not.

It seems to flare up especially when I get a cold.

I’ve already lost one job due to being off work so much.

When I was put on HU my platelets were 515. I was 62 and until that point I had been in baby aspirin - no muscle a pains!!!

Does anyone else have this Robles since starting HU

[hunter5582]

Back pain, tetany (muscle pain/spasms) are known side effects of HU.

mayoclinic.org/drugs-supple... .

No way to know if this is what is going on for you. It is important to understand that HU is a toxic substance. While many people can tolerate it, not all can.

Quote from the NIH - Toxnet

"Hydroxyurea is a highly toxic drug with a low therapeutic index, and a therapeutic response is not likely to occur without some evidence of toxicity. Hydroxyurea therapy may be complicated by severe, sometimes life-threatening or fatal, adverse effects."

What may feel like muscle pain could be something else. Sometimes pain gets referenced in some unexpected ways. Known side effects of HU include pancreatitis,

and hepatotoxicity. Splenomegaly can also result directly from the MPN - not the HU. HU can cause asthenia (weakness/low energy), but MPNs can cause chronic fatigue. there is no reason to think any of the more serious side effects apply to you, but these things are pretty straightforward to rule out. Better to not make assumptions and check things out if you are having issues.

With your platelet levels only at 515, not clear why you would go on HU. Even at age 62, most docs would not treat low grade thrombocytosis with HU in the absence of symptoms like thrombosis, TIAs or significant splenomegaly. You did not indicate whether you have ET or PV. How are your other blood cell numbers? The actual risk of thrombosis is linked to leukocytosis and erythrocytosis (in combination with thrombocytosis). There is actually increased risk of hemorrhage when platelet levels increase for some of us with MPNs.

Sorting all of this out can be quite bewildering. Unfortunately, many docs (even hematologists), have very little experience with MPNs due to their rarity. You may want to seek out a consultation with a MPN specialist if your doc is not an expert. Here is list of patient-recommended docs mpnforum.com/list-hem./ .

I would encourage you not to just ignore the side effects you are experiencing. Some docs tend to blow off patient concerns. Assertive patients will receive higher quality care. Passive patients will not. While it is most likely a minor side effect you are experiencing, you should nit just assume that it is. Even if all that additional testing does is relieve your mind, your mind is a pretty important thing to keep in a good state.

All the best.

[Digger031145 in reply to hunter5582]

Thank you for your reply hunter5582

I am ET JAK2+.

Sorry I forgot to put that in my post.

I didn’t have any symptoms when I was diagnosed in 2007 age 54.

I was put on baby aspirin until age 62 and platelets at 515.

This muscle pain in my mid to upper back left side seems to happen when I’ve got a cold and for several days afterwards.

I have to resort to taking paracetamol and ibuprofen. It very debilitating and drains me.

I thought yesterday, that because my white cells are low they cannot fight the colds and the virus then affects my muscle.

I’ve never had any symptoms at all of ET and not had any events.

I read somewhere that colds can give you myosotis which is inflammation of the muscle.

I’m now 66 and still work part time but I had to take Friday off as I was in so much pain.

This problem all started in 2015 a few weeks after I was started on hydroxycarbamide . I started it in the February and first occurrence was end of March . I had to have 3 weeks off work.

By November 2015 I had to give up that job as I’d had too many weeks off work .

I also do get a lot of colds now, where as prior to HU I very rarely got a cold and certainly didn’t get muscle pain

Thank you for reading this

[hunter5582 in reply to Digger031145]

HU is an immunosuppressant. It is important to avoid live virus vaccination and infections of any sort. HU reduces all hematopoiesis - reducing platelets, leukocytes (white cells) and erythrocytes (red cells). If your leukocytes are on the low side, then your body will not be as able to fight off infections.

I have JAK2+ PV. Was ET (diagnosed over 30 years ago) until about 6 years ago when the MPN progressed into PV. Despite the progression, I have never had any symptoms other than very mild splenomegaly. The way the MPN effects each of us can be quite different. The "standard protocol" for treatment may be right for many MPN patients, but not for all. It is very important to have an individualized treatment plan that matches what your specific needs are.

Since you are JAK2+ one of the important steps is to find out what your JAK2 mutant allele burden is. The test is called a JAK2 Mutant Allele Quantitative Analysis (or similar). The lower the burden is, the more likely you are to have a mild course of the MPN. People will a burden less than 50% tend to be more mildly affected. There are also non-driver mutations that may affect the course of the MPN (e.g. ASXL1, TP53). Most docs never check these. Given that you are so mildly effected by the ET - they are likely not present.

What really matters is to find a doc who has the KSAs to look at your pattern of symptoms, your genetic profile, and your response to medications; then use this information to create a treatment plan based on your unique profile. HU is not a benign substance. While some tolerate it, not all can. I am one of those that cannot tolerate HU. While HU use is still in common practice, some docs have moved away from its use. There are docs who are taking a different approach in how they think about treating all MPNs - looking at symptoms rather than numbers on a lab report. The MPN specialist I see does not favor "sanitizing" numbers in the absence of symptoms. Below is a quote form that he told me regarding my case of PV.

"With respect the treatment of your disease. Since you have it for so long, what see is what your going to have. Phlebotomy is the only necessary therapy. Aspirin is unnecessary unless you have symptoms that require it. A high platelet count doesn't cause thrombosis; it can cause bleeding. If your surgeon is concerned, this is easily testable. I certainly wouldn't take iron unless you want to keep getting extras phlebotomies. For polycythemia vera, chemotherapy is a fool's errand except in specific circumstances; if you need it for a tumor elsewhere, that is fine because it won't affect the polycythemia vera.

" (Note - I just had surgery to remove a brain tumor. Also have phlebotomy induced anemia).

I have no idea what the best course of action for you is. I am not a doc - just a MPNer who has found that sometimes the treatment is worse the the disease. Lots of docs rely on standard protocols that do not always work for specific patients. I hope you get your own situation figured out ASAP and receive the high-quality individualized care you deserve.

[Digger031145 in reply to hunter5582]

Thanks for you detailed reply.

Is your Dr an MPN specialist?

I wish I could find one that went on how I was and not by my age

[hunter5582 in reply to Digger031145]

I have two hematologists. My regular local hematologist is a great doc, but I am only his 6th MPN case (second PV case) in 20+ years of practice. I also have a MPN-Specialist doc who I consult with. The MPN Specialist provides consultation to me and my regular hematologist. The two docs do not always agree. The way it works is that the docs make recommendations - I make decisions. My body-my choice. I do have to travel to see the MPN specialist. it is worth it. Check out that link - that is where I found the doc mpnforum.com/list-hem./ . List docs world-wide.