What is the term for the enhancement of the effect of one drug by another drug?

The correct term for the enhancement of the effect of one drug by another drug is "potentiation." In pharmacology, potentiation occurs when one drug increases the effect of another drug, often resulting in a stronger or more prolonged therapeutic effect than either drug would produce individually. This can happen through various mechanisms, such as one drug enhancing the absorption, distribution, metabolism, or elimination of the other, or by affecting the same biological pathways or receptors.

For instance, consider a scenario where Drug A has a mild analgesic effect, and Drug B, when administered alongside Drug A, significantly increases that analgesic effect. In this case, Drug B is said to potentiate the effect of Drug A.

While synergism refers to a situation where two drugs together produce a combined effect greater than the sum of their individual effects, potentiation specifically focuses on the enhancement of one drug's effect by another without necessarily exceeding the sum of their individual effects. Combination could refer to any type of multi-drug treatment and does not specifically denote enhancement. The term reaction can describe any interaction between drugs but does not specifically imply enhancement.