Nuts and nut oils are in more products than most consumers think. If you have a nut allergy, that fact can be more than a little harmful. It's important, then, to recognize symptoms of an allergy to nuts and nut oils. Nut allergies, like all food allergies affect most areas of the body, but the first sign usually surfaces in the mouth.

Tingling of the Lips or Mouth

If you have a nut allergy and eat a food or product with nuts in it, you may experience tingling in your lips or mouth. This tingling is a common reaction to the nut or nut oil and usually occurs before any swelling.

Stomach Pains

In some cases, you may experience stomach pains or feel sick to your stomach after ingesting a food containing nuts or nut oils. In severe cases, vomiting may even occur as your body tries to purge the food.

Redness or Rash

You may also develop some type of rash, redness or hives after eating a food or using a product containing nuts or nut oils.

Swelling

Allergies to foods, like nuts, can cause mild to severe swelling, especially around your lips, mouth and face. In severe cases,your throat may also swell, leading to difficulty in breathing and a lack of oxygen to the body. Swelling of your throat can eventually cause you to pass out.

Heart Rate and Blood Pressure

In extreme cases, an allergic reaction to nuts can cause your heart rate to increase or blood pressure to lower. In both cases, you may collapse or faint.

Anaphylaxis

When a severe reaction occurs and causes you to pass out because of lack of air or low blood pressure, it is called anaphylaxis. If you are not treated quickly for anaphylaxis, you could become unconscious and may even die.

Source:

Patient UK. Nut Allergy: What are the Symptoms?

WebMD: Living with a Nut Allergy

KidsHealth: Nut & Peanut Allergy