[igoldsmid]

Is vitamin K2 safe to take with thalidomide?

by igoldsmid on Wed Jan 07, 2015 1:37 pm

I used to take vitamin D3 and K2 (menaquinone MK7 type). I have long understood that D3 + K2 is highly positively synergistic under normal circumstances.

I am currently on VTD (Velcade, thalidomide, dexamethasone) induction and there are various warnings of possible increased blood clotting events with K2, especially when combined with thalidomide. I am on 100 mg thalidomide daily. I am also on daily dalteparin sodium (Fragmin) 5000 IU / 0.2 ml subcutaneous daily.

Does anyone have any insight on this clotting issue with K2? How safe or unsafe is it with VTD induction. Should I err on the side of caution and not take it? Dosage? I used to take 100-200 mcg vitmain K2 MK7 daily.

Thank you!

Moderator's Note: This posting originally was made to the forum thread "Do you take supplements and, if so, which ones?". However, due to the very specific nature of the question, we thought it best to move it to a discussion thread of its own.

[Dr. Ken Shain]

Re: Is vitamin K2 safe to take with thalidomide?

by Dr. Ken Shain on Wed Apr 01, 2015 1:22 am

I cannot answer your question directly with data.

I am not sure why you are taking vitamin K. It is an important co-factor for the hemostatic cascade, the sequence of proteins that forms clots. Coumadin (warfarin) works as a blood thinner by in­hibiting the action of vitamin K on the clotting cascade. For instance, if someone has taken too much Coumadin, and their PT/INR is markedly supratherapeutic (too high), vitamin K can be used to reverse the effects of Coumadin.

The Fragmin you are on does not work in the same manner as Coumadin. But it is being used to prevent you from getting DVTs or PEs while on thalidomide. As such, I would recommend that you not take vitamin K2 while on thalidomide.