i also could add that we are lucky that son is not asthmatic, however does have inhalers for allergic reactions , as his throat/chest close.
lots of asthma in my family am amazed that he doenst have it!
yeast extract is not a 'real ' allergy, apparently (so docs explained to me) but of course is serious and does cause anaphylaxis.
yeast extract has a high histmine content, and as son is IgE allergic , has a higher level of histamine in body than a normal person.
yeast extract causes histmine content to overflow, and kicks in to allergic reaction.
in fact, thats a good explanation for IgE allergy, (to be frank here, am bit concerned that people are confused with this, it doenst say much for the medical support you are getting!)
an allergic person has a higher than normal amount of histamine, if you think of a pint glass, (picture it now...) a normal person without allergies, would have a thin level at the bottom.
a allergic person has a pint glass half full. this is before exposure to allergens,
in my sons case, his level gets higher in winter (centrol heating on=high dustmite), and then spikes higher now, in march (tree pollen allergy) currently he only has a small gap at the top, which is all the space he has to overfill to go in to anaphylaxis IF he accidently ingested one of his food allergens.
when younger, when dog allergy spiked, he would have difficulty breathing during this time of year near , or in a room /or car that a dog had been in.
thankfully thats much, much better now.
for those with asthma, impact of allergic reaction truely depends on asthma control.
a allergic persons symptoms are immediate and of course most of us are pretty good at recognising them, due to being a constant wittness to them, or personal experience.
its getting to know how to look for the killer symptoms and ignoring the outward visable ones, and concentrating on the lowering blood pressure signs and breathing problems.
this is why its important to know the difference between intolerance and ige allergies, as 'allergy' is such a loose term , one means life possibly at risk,
and other means days of tummy pain,vomiting and D sleepless nights and sore guts. (not dissing intolerence folks, am aware that its not fun, and can be very nasty, and have impact on long term growth etc)