come on v.2
1. (drugs) for withdrawal symptoms to start affecting a narcotics addict.
|Lang. Und. (1981) 102/1: To feel the habit coming on. See to be sick.‘Lang. of the Und. Narcotic Addict’ Pt 2 in|
2. (drugs) for a drug to begin affecting its user, esp. of a hallucinogen (which takes a short time to enter the bloodstream and hit the brain).
|Really the Blues 92: Muta never came on like that.|
|No Beast So Fierce 214: The marijuana came on quickly.|
|(con. 1969–70) F.N.G. (1988) 103: Whatever that pill is, it’s coming on hard now.|
3. of a woman, to start menstruating.
|Eng. Madam 45: I’d clicked with him once before, and he gave me some pills [...] and I came on again after taking them.|
|Powder 130: All the girls had come on their period that night.|
|OnLine Dict. of Playground Sl. [Internet] come on v. to begin menstruation.|