How long is dextroamphetamine in the bloodstream?

I took 500mg, and i weigh 150lbs. i still feel messed up now and its 26 hours after ingestion.

Dextromethorphan (DXM) stays in your blood on average about 4 days. I repeat, that's on average. The range of days is around 3 - 5 if you are not being safe about it. If you want to be completely safe because of a drug test, make sure you have a week of sobriety before the test so you come out negative for drugs. Remember, DXM is the only over-the-counter (OTC) drug that shows up in tests now, and it shows up in most of them. Also remember that the only drugs that can be found are the ones they are testing for. If they aren't testing for it, they won't find it.

I do not condone drug use... In other people... lol... ok well i do not promote it anyway...