There was no increase of stress hormone concentrations in experienced subjects. The reduction of [noradrenaline] and [adrenaline] during scuba diving seems to be a reaction to orthostatic relief caused by external hydrostatic pressure on peripheral vasculature. The activity of the vegetative nervous system might be estimated from HR variability if interference among pulse watches can be avoided.

Because of its clinical benefit and the lack of side effects Picrotoxin is a reasonable alternative in medical long- term treatment of Menière's disease, which should have an important role in the treatment cascade.