Figure 3.

Different levels of drug-drug interactions. The figure shows that the effect of combining two drugs can be elicited at the level of target (drugs targeting different sites within the same target via similar or different mechanisms), pathway (drugs targeting different signaling proteins within the same cascade), processes (drugs targeting different processes contributing to the disease phenotype) and patient (where the effect of the drug combination will depend on how the drugs will influence each other’s ADME properties and pharmacological effects).