Potentiators

Potentiators are substances that increase the effect of another agent or process. In pharmacology and biochemistry, potentiation can enhance therapeutic efficacy, extend duration of action, or reveal latent activities of a compound. Potentiation can arise from pharmacodynamic interactions, where two agents act on the same receptor or pathway to produce a larger effect than expected from their individual actions, or from pharmacokinetic interactions, where one substance alters the concentration of another by affecting absorption, distribution, metabolism, or clearance.

Mechanisms of potentiation can be broad. Pharmacodynamic potentiation involves synergistic or allosteric effects that amplify signaling or response at the target site. Pharmacokinetic potentiation involves changes in drug exposure, such as enzyme inhibition that slows metabolism and raises blood levels, or altered absorption and transport that increase systemic availability. Both forms can influence efficacy and safety.

Examples include ritonavir, used as a pharmacokinetic booster to increase levels of other antiretrovirals by inhibiting metabolic enzymes. Dietary components such as grapefruit juice can inhibit intestinal enzymes and transporters, altering drug exposure. Co-administration of central nervous system depressants can markedly intensify sedative effects, increasing the risk of adverse outcomes.

Applications and considerations. Potentiators can be desirable in therapy to achieve effect with lower doses or to overcome resistance, but they also raise the potential for adverse effects and dangerous drug interactions. Careful dose adjustment, monitoring, and consideration of individual variability are essential. In research, potentiators help explore pathways and optimize combination therapies while distinguishing true pharmacodynamic synergy from exposure effects. See also: drug interactions, synergy, pharmacokinetics, pharmacodynamics.