Refractory period

In general, a refractory period is the time during which a excitable membrane does not respond to a stimulus that normally generates a response.

---

In sex, the refractory period is a recovery phase after male ejaculation during which it is physiologically impossible for almost all men to experience sustained erection and additional ejaculations or orgasms. The penis may be hypersensitive and further sexual stimulation may even feel painful during this time frame. The refractory period varies widely between individuals, ranging from minutes to hours. An increased infusion of the hormone oxytocin during ejaculation is believed to be chiefly responsible for the refractory period and the amount by which oxytocin is increased may affect the length of each refractory period. Unlike men, women do not experience a refractory period immediately after orgasm and in many cases are capable of attaining additional, multiple orgasms through further stimulation.

---

In cardiac physiology, the refractory period is the time between heart contractions. Problems with the refractory period in the major pathways of the heart are known as heart block.