Mixed inhibition is a type of
enzyme inhibition in which the inhibitor may bind to the enzyme whether or not the enzyme has already bound the substrate but has a greater affinity for one state or the other. It is called "mixed" because it can be seen as a conceptual "mixture" of
competitive inhibition, in which the inhibitor can only bind the enzyme if the substrate
has not already bound, and
uncompetitive inhibition, in which the inhibitor can only bind the enzyme if the substrate
has already bound. If the ability of the inhibitor to bind the enzyme is
exactly the same whether or not the enzyme has already bound the substrate, it is known as a
non-competitive inhibitor. Non-competitive inhibition is sometimes thought of as a special case of mixed inhibition.