The claim that sex cures headaches is commonly quoted. For example, from 10 Reasons Sex is Good For You:
10. Sex Can Cure Headaches
A South Illinois School Of Medicine study on 52 migraine sufferers reported that 16 experienced considerable relief after an orgasm and another eight had their headaches completely gone. No reason now to say, "Not tonight honey, I'm having a headache."
Sex = endorphins = pain killers.
Does sex just act as pain killer and cure headache's symptoms: pain, or there is some other substance released that cures the causes?