In
pharmacology, the term ceiling effect refers to the property of increasing doses of a given medication to have progressively smaller incremental effect (an example of
diminishing returns).
Narcotics, such as
nalbuphine, serve as a classic example of the ceiling effect; increasing the dose of a narcotic frequently leads to smaller and smaller gains in relief of
pain. In many cases, the severity of
side effects from a medication increases as the dose increases, long after its therapeutic ceiling has been reached.
See more at Wikipedia.org...