Bisphosphonates drug interactions

The interaction between bisphosphonates and plasma proteins is not well understood, but it is known to be influenced by both calcium and iron ions [38]. The addition of calcium to human plasma in an in vitro study increased the proportion of plasma protein-bound versus free pamidronate, whereas the addition of calcium chelators reduced the proportion of drug bound. Similarly, the addition of ferric ions to plasma increased the proportion of plasma protein-bound versus free pamidronate [38]. 

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