Oooohhhh - that sh!t is evil!!
Not very wisely I downed a bottle before flying out of Thailand many years ago.. by the time I got to the airport I was nearly doubled over with stomach pains and had to see the airport nurse. They took me aside and i swear i thought I was gonna cop the rubber glove treatment!!

Luckily all I got was some stomach calming goop.. whew!

The Thai stuff contains good ol' amphetamines (never been a fan of phets) and as i can testify after not sleeping much at all that night (I took it late morning) it certainly does work!
BTW San Thrip whiskey also contains phets.. beware the evil that lurks iside the brown bottle. Ha ha - they just can't get enough of the stuff over there. All legal too..
One morning I had a king-sized tequila hangover so scooted down to the pharmacy to get some paracetamol and possibly with codeine. One mention of codiene to the pharmacist and he was trying to offload enough psuedoephidrine to knock over a bull! "Er.. just the paracetmol is fine ta, no really, no really - no thanks. look, I don't want anything but paracetamol!!"