Ceiling Effect
The pharmacological principle that increasing the dose of a drug beyond a certain point produces no additional therapeutic effect, though side effects may continue to increase. A ceiling effect can result from partial agonism, receptor saturation, or physiological limits of the effector system. Drugs with ceiling effects may have improved safety profiles for certain endpoints.
Examples
- Buprenorphine: ceiling effect on respiratory depression but not on analgesia at clinical doses
- NSAIDs: analgesic ceiling around 400 mg ibuprofen equivalent, further doses add only side effects
- SSRIs: serotonin transporter occupancy plateaus at moderate doses (~80% at standard doses)
Did You Know?
The pharmacological principle that increasing the dose of a drug beyond a certain point produces no additional therapeutic effect, though side effects may continue to increase. A ceiling effect can …