Heads up. Absorption rates topically are 15-20 x higher than orally.
The standard dosage of 25 drops would be 750-1000mg of b1 and 1.5g to 2 grams of b6. It might be jacking your metabolism up and you don't have the resources to handle it so adrenaline and cortisol kicked in.
I'm having very similar symptoms after a dose of antibiotics in January.
Thanks for your feedback, @Sam321. I've played around with the dosing of B vitamins a fair amount, and if anything, the oral route seems to produce significantly stronger effects for me. And my endotoxin symptoms often seem to get worse when I cut back on the B vitamins. But I'll rethink my dosing and watch for the effect you mention (insufficient nutrition to keep up with the B vitamins).
If you're experiencing similar symptoms, I'd like to read more about your case. Have you posted a thread on your GI problems?