So if symptoms do not correlate very well to specific allergies, what does correlate and now can you relate symptoms to allergen?
The answer is to watch out for possible symptoms, and then try to notice if these symptoms occur when you come into contact with a specific allergen (or some time later).
Even this can be challenging if you experience delayed onset allergies. For example, you might eat something today and feel fine, but then not feel so great after a day or two. The good news is that delayed onset allergies are typically less serious than immediate allergies (which carry with them the risk of anaphylactic shock.
So do watch out for symptoms. Also pay close attention to timing.
While there is a challenge with allergy symptoms varying more from individual to individual, it is still possible to make broad assumptions about symptoms versus allergen. On the whole, the way you contact the allergen is more important than the allergen itself.
For example, if you have a contact allergy, for example to nickel, you will most likely end up with a rash. If you are allergic to mold, a runny nose is a typical reaction. On the other hand, dust allergies can cause brain fog, which can also confused with mold allergy symptoms.
Food allergy symptoms can be much more challenging. Any type of symptom is possible. For example, stomach upset is a typical food allergy symptom, but not all food allergies cause stomach upset. Food allergy symptoms can also include skin allergy reactions (among a diverse group of other possible symptoms for your body to randomly choose from), just the same as a direct contact allergy.
I generally use the broad term “allergy” to mean both a classic allergy and a hypersensitivity. There are certainly medical differences, and only an allergy in the true sense of the word can cause anaphylaxis. But when it comes to symptoms and deciding what you should avoid, the two conditions can be managed in similar ways (as long as the allergic reaction is mild).
All this said, there certainly do seem to be consistent allergic reactions in many people to some allergens, for example pollen (i.e. hay fever). In this case, sneezing, watery eyes, congestion and an itchy throat are typical.
What ever symptoms you do have, the main differentiation between allergy symptoms, and some other cause such as flu or a cold, is that allergy symptoms tend to either be seasonal or chronic, where as a viral infection such as the flu tends to last anywhere from a day to a week.
Seasonal allergies are pretty easy to spot because what ever symptoms you have, they tend to occur every year at about the same time.
Contact allergies can be relatively easy to spot too, if you know what to look for. If you have hives or a rash in a particular part of your body, and it turns out that this part of your body is coming in contact with something, metal for example (jewelry, a belt buckle, a watch band etc.), then you probably have a contact allergy. Remove the suspected and see if the problem goes away after a few days.
See the separate article on anaphylaxis for details about anaphylaxis.
A complete list of allergy symptoms is probably impossible, since there are probably a few individuals with unusual symptoms, but the most common allergy symptoms is possible.
Keep in mind that having one, several or all of the symptoms on this list does not automatically mean you have an allergy. Many other conditions can cause the exact same symptoms. The key is to recognize the symptoms and the timing, as noted above.
See the article Allergy Symptoms for a list of symptoms that many people experience.
Also see the anaphylaxis article for a list of symptoms specific to anaphylaxis.
- Self-Testing for Food Allergies
- Top 20 Food Allergies with Delayed Reactions