Efficacy

Definition

The maximum therapeutic effect a drug can produce, regardless of the dose given. A drug with higher efficacy can achieve a greater maximum response than one with lower efficacy, even if the latter is more potent.

Example

Morphine (full opioid agonist) has greater analgesic efficacy than buprenorphine (partial agonist) — morphine can produce a stronger maximum pain relief.

Related Terms

Agonist Dose-Response Curve Potency

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