I've been on Ibrutinib for close to 3 years and doing well on it except for fatigue. My hematologist is switching me to Acalabrutinib to see if the fatigue improves. When I went to pick up my prescription today the pharmacist went over all the possible food/vitamin interactions. I know the usual about grapefruit and Seville oranges but she said there is an interaction with vitamin D. I told her I've been taking 4000IU of vitamin D the whole time I was on Ibrutinib and wasn't told this when I started Ibrutinib. I didn't ask what website she used to get this information. She said the vitamin D may decrease the effectiveness of Acalabrutinib but it wasn't tested with Acalabrutinib, It was tested with a statin that uses the same liver pathway as Ibrutinib/Acalabrutinib.
I can't believe this is true and I don't want to stop taking my vitamin D. She said I could take 1000 IU but not the 4000. My vitamin D is in the normal range, 156 nmol/L.
Anyone heard of this interaction?
Written by
Elle_V
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When I started Acalabrutinib I asked if I should carry on taking Vit D. The answer was an emphatic Yes! I take 2,000 ius a day and no issues. Been on Acalabrutinib 22 months and results are great. No tiredness issues
I stopped taking vitamin D without discussing it with the clinical trial team before commencing my acalabrutinib + venetoclax + obinutuzumab trial. When my haematologist checked it during the trial, my serum level had dropped very low and he recommended I restart on my previous dose of1,000 IUs a day. On retest some time later, my serum level was back into the normal range.
I started on Acalabrutinib in January this year. In the pretreatment check my consultant asked for a list of any medications and supplements I take. I was advised there was no issue taking vitamins d3 and k2.
I also take the multi vitamin berocca, which was ok.
I was advised not to take Spirulina because of possible interaction with Acalabrutinib and had previously stopped taking echinacea as this is not advised for leukaemia patients.
Thank you,Recently diagnosed with osteoporosis in right hip, so apart from high dose Vitamin D are you on any other treatment. I am trying to avoid Alendronic acid.
I would have thought that Phamacist and CLL patient, Tom Henry, would have mentioned this interaction in the CLL Society article he wrote about Acalabrutinib a couple of years before he died:
This sounds bizarre to me. Even if true, How would this person know that 1000 IU were OK, but 4000 IU isn't? That's not how drug interaction software works. Ask for a printout/hard copy of this interaction.
I would ask about the supposed source. Unless there is really new data just published, I don't think this is true. The free interaction checking software I can access doesn't show a known interaction with Vitamin D.
Even if there *was* an interaction, it's possible it's more of the "don't abruptly stop the Vitamin D" type than a "do not take these 2 meds at the same time" type.
While there is some data indicating *statins* may affect Vit D blood levels, just because a med uses the same liver enzyme pathway as a statin doesn't automatically mean other meds may also affect Vitamin D levels. And since statins appear to *lower* Vit D levels, one might increase a Vit D dose in response, not decrease it. I think there has been some sort of miscommunication?
Drugs.com does not show an interaction between either form of Vit D and acalabrutinib:
The pharmacist said they use 2 different databases and one of them didn't show an interaction and the second database which she said is more herb based is the one that showed the interaction. Bizarre is the right word, when she told me this I already had it in my head that there was something off when she gave me this info so didn't even think to ask what website it was. At my next visit, I will try to remember to ask what database they used. I know in the past they have used the Memorial Sloan website mskcc.org/cancer-care/diagn... tried looking up Vit D and Ibrutinib or Acalabrutinib and also statins but couldn't find anything.
I started on ACP-196 (Alcalabrutinib ) first trial, have been on it for 6 or 7 years and now have mutations and becoming resistant and pursuing my next line of treatments, this entire time, I have been on 5000 IU vitamin D-3 twice daily and continue that regimen as I have new mutations now to deal with.
I’m not a biochemist but I don’t think vitamin d is a problem like other drugs that block CYP3A. Certain antibiotics, and grapefruit interfere with that pathway.
Seems to me that vitamin d seems to do the opposite. It keeps the levels of CYP3A healthy, and if vit d is too low the levels of CYP3A can be too low to metabolise drugs effectively. So seems important to keep vitamin d level up?
My consultant has said it’s not a problem fir me to take vitamin d with V & O in the near future. I might be interpreting the data wrongly so would appreciate anyone else’s thoughts.
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