You are here

Dasatinib Side Effect Timing

Categories:

I've been on dasatinib for ~5 months and have been pretty much side effect free the whole time.

For the last four to five days I've had pretty much constant mild nausea and fatigue, nothing debilitating. Almost like a mild hangover that won't go away. Temperature is normal (often times somewhat low), took a rapid covid test and it was negative.

I know this is a common side effect for all TKIs, but is it alarming that it would happen out of the blue like this after 5 months?

I don't see the hematologist for another 3 weeks, and I also don't know the results from my first PCR test at 3 months. I was told I'd be called if there was anything out of the ordinary, and never received a call back.

I also contacted the oncology nurse line at my hospital, and they were not concerned. Being relatively newly diagnosed, and having no side effects up until now, I am anxious that my TKI may not be working.

What is your dose?

When was your last complete blood count (CBC) taken?

Early in treatment, your blood system is going through a dramatic transition from leukemic back to normal. Often with TKI's and particularly with dasatinib, myelosuppression can set in where your blood counts, especially white blood cells (neutrophils), but also red blood cells can fall quite low as a "hole" develops during the transition. It is self correcting, but takes time and often drug breaks or drug dose reductions are needed. It is the anemia, in part, which can lead to dramatic fatigue and nausea. I had to have many drug breaks early in my treatment with dasatinib and experience your same symptoms. My red blood count became low and tool many months to recover.

You should get a CBC taken straight away. Should your counts be too low, you may need to stop dasatinib for a short time while your counts recover. Over time, this will correct. But vigilance early in treatment is key.

Thanks Scuba. I'm taking 100mg.
My WBC was 320k at diagnosis in August/21, blasts ~9%.

My last CBC was the end of November. The hematologist walked in the room and said "Well, you're boring". Everything was pretty well in range.

My platelet count dropped initially during treatment to ~100 (no units of measure on my report, poor quality control imo :) ) but quickly rebounded.

Red cell count, ERC, correct? Was 4.77 in my last CBC.

Given that I didn't experience a great deal of myleosuppression in the first few months, is it still something to look our for?

100 mg dasatinib is now considered a high dose and the old standard. Depending on where your bcr-abl level is currently, you could lower your dose to 50 mg and potentially achieve a better result. More drug is not necessarily better when it comes to dasatinib. It could be the cause of your fatigue. Our red blood cell count is good from November, but you need to know what it is today (February). Hemoglobin amount is also important to track.

You should have a CBC taken to verify your blood counts are normal or near normal. The first year of TKI treatment sees many changes and adaptations by the body.

Long-term follow-up of lower dose dasatinib (50 mg daily) as frontline therapy in newly diagnosed chronic-phase chronic myeloid leukemia