Tachyphylaxis

Last updated August 2026

A rapid drop in response after repeated doses over a short period — a faster form of tolerance. Sometimes discussed with frequently dosed peptides.

Unlike gradual downregulation, tachyphylaxis can appear within hours or over a few closely spaced doses, and the response often returns after a short pause. It is one reason spacing or cycling is discussed for peptides taken frequently. It is a biological response to timing, not a measurement issue, so it does not change how concentration or units are calculated for any single dose.

Educational reference only — not medical advice. Always follow the guidance of a qualified healthcare professional.