I can't say that I have ever split an Imitrex, as I usually need at least 100 mg to knock out a migraine. For me, it takes about 30 minutes after taking a tablet for it to kick in. I do not think the tablets are coated, so I do not see why you couldn't split them. You might also try the statdose injection. The shot is self-administered and feels like a hefty bee-sting, but the migraine relief is more immediate. I keep both as options and judge which to take when based on how fast the onset of the migraine is. I have been battling the migraines for over 20 years...good luck getting rid of yours.