Tolerance is not an allergic reaction, but is worst than it.
Could be...
No but someone could be allergic to sand.
Some medical reasons why someone could not speak in a legible manner are: alcohol poisoning, allergic reactions, a migraine, a head injury, a stroke or a neurological disorder.
Because those who ARE allergic to the dye, could possibly be VERY allergic, and could suffer severe reactions.
You will have a reaction, but much lower than if you were eating them yourself. If you have a strong reaction to mushrooms you could lower the reactions by having him/her brush their teeth.
Ingredients in them are chosen to make it unlikely as possible that they could cause reactions. But you can always look at the ingredients to make sure.
Yes, it could. An allergic response can trigger an exacerbation of asthma. Common types of asthma attacks are actually caused by allergic reactions.
There could be any number of reasons including, but not limited to, allergic reactions and pregnancy. See your doctor.
Bread is not known to cause headaches, but certain allergic reactions to the bread could lead to headaches.
Well they could be allergic to prawns (I am).
it ca be seen as unprofessional, and someone could be allergic to it
Hornets can kill someone if they are allergic to the venom. And if enough of them sting someone, they could go into shock and that could be a problem.