Which pain relieving substances are released by a human orgasm?
The hormone oxytocin is the most common hormone released during sex. Studies have proven that this hormone is a natural pain reliever. Also referred to as the love hormone, this hormone is released from the brain before orgasm. It is released because the part of the brain associated with pain is stimulated during sexual arousal.

Endorphins are also released during orgasm and have natural pain-relieving qualities. They have a similar chemical structure to morphine and are thought to be involved in controlling the body’s response to stress, regulating contractions of the intestinal wall, and determining mood.

I hope that helps!
During orgasms, endorphin release has been reported to occur across the central nervous system and other parts of your body; the levels vary based on whether the person experiencing them identified as female vs male.
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