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Peak-to-Trough Ratio

Meaning

The Peak-to-Trough Ratio is a critical pharmacokinetic metric utilized in clinical pharmacology to quantitatively assess the magnitude of fluctuation in a drug’s plasma concentration between its highest (peak) and lowest (trough) points during a specific dosing interval. A low ratio is clinically desirable as it signifies a more stable, sustained therapeutic drug level, which is essential for maximizing efficacy and minimizing concentration-dependent side effects, especially with hormone therapies. Clinicians use this ratio to evaluate the physiological consistency delivered by different drug and hormone delivery systems.