I think the ld50 is 55mg/kg but this is all IV
So it would be 129 x 25mg.
You should be able to find it out from the pharmaceutical companies that make it though. Try sending them an email.
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I've tried Joseph Clough's and he does say "vomit"and "being sick", which at the time made my heart leap mid-relaxed state - not pleasant. But now I know he says it it's not as bad.

The fact you can time it sounds like it's a physical/anatomical problem, maybe Crohn's or Coeliac.
Hope you can get an answer soon; maybe further testing with an ultrasound or CT would help.
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You survived it, coped fine and your body did its own thing - what it needed to do. :)
I'd be inclined to say I'm not sorry you threw up, I am really sorry you had to experience the distress...

I'm not sure exposure therapy to v* would help much if it's a control thing. Well it may help to see how you can v* then immediately regain composure.
I would say CBT is more likely to offer help...