Mine usually last 1-2 days. If I'm on day 2 and the Imitrex/Tramadol hasn't worked, it's time to go to urgent care. Usually an IV bag and some Reglan sets me straight. One time they had to give me Dilaudid. That was...interesting, and it's not an experience I'd like to repeat. I'm on prophylaxis now, so they have cut down quite a bit. But I still get 3-4 a year, usually around ovulation.