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Neverfly
2008-Sep-26, 06:33 AM
This one's coming from the housemate's side of the fence.

What role does the Immune system play in allergies?

HenrikOlsen
2008-Sep-26, 07:58 AM
Aren't allergies generally considered to be immune system overreactions?

Neverfly
2008-Sep-26, 09:04 AM
Aren't allergies generally considered to be immune system overreactions?

That is what I had thought.
The topic came up because she seems to get sick easily.

But you would think that heavy allergies would be the sign of a strong immune system.

clint
2008-Sep-26, 10:01 AM
Maybe strong, but also probably inefficient.

An immune system that wastes a lot of effort fighting harmless stuff,
might sometimes become too distracted to fight the real enemy.

HenrikOlsen
2008-Sep-26, 10:41 AM
But you would think that heavy allergies would be the sign of a strong immune system.
They are the sign of an immune system that is out of tune, I don't find it illogical to see it react too strong on some things and at the same time too little on other things.

JohnD
2008-Sep-26, 11:20 AM
Do not confuse "allergy" and "sensitivity".

Allergy is where the immune system, most often for our benefit, acts against us. Sometimes, the allergic response is grossly exaggerated. There is a massive release of histamine, with bronchospasm (airway constriction), if the cause is something eaten with swelling of the upper air passages and vasodilation (widening of blood vessels). The suffering patient wheezes in an acute asthma-like attack or chokes as the inside of their throat swells, their blood pressure drops, their heart races and they faint. This can be a life threatening situation, termed anaphylaxis.

Sensitivity to drugs and other compounds is an unusually strong response to a normal effect of the drug, or to a side effect. The response is confined to a single or a few effects, and is not due to the immune system. The reason is unknown, often as the reported effetcs are so multiple in the individual and the population. It's hard to study something that seems cause so mnay different problems for different people, in whom no other abnormality can be found.
What is known is that the hoped-for response to many drugs varies across the population, which can be divided sometimes into 'responder' and a 'non-responder' groups.

This variation in response may be genetically determined. It isn't a general guide to the state of the immune system. I would love, as would immunologists, to know what is meant by an "immune system out of tune", which is a bit like being asked to daignose being " a bit poorly". Certainly, we are exposed to a wider range of compounds than a century or so ago, so more sensitivities may show themselves, and there is an increased incidence of asthma and anaphylaxis, which is not explained. Also certainly, individuals have a different mental response to minor symptoms. Some find them disabling, others would not dream of letting them stop them doing anything they want or have to do.
The best example is the 'man cold'! What woman goes to bed with a sniffly nose? Even if they feel dreadful, have a temperature and are all blocked up? Unless of course the man catches cold on a Friday.

John

Euniculus
2008-Sep-27, 06:12 PM
What role does the Immune system play in allergies?

Everything, how complex of an answer do you want?

I can give a simple explanation or a very complicated one.

Neverfly
2008-Sep-27, 07:38 PM
Everything, how complex of an answer do you want?

I can give a simple explanation or a very complicated one.

Rock on- A Very Complicated one will do nicely:)