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The duration of allergic response

I used tea tree oil before many times mostly for its antiseptic properties. What I didn't know before using it last time, is that my body developed an allergy to the oil.
I put one drop of the oil on my skin and within few hours got a very itchy rash. The rash area was way bigger than the contact area and it was very irritating.
Almost two weeks later and I still have the rash. It is smaller, and it doesn't bother me that much, but it is still there. Two weeks after the contact with an allergic substance, and my body is still reacting to it!
Is the reaction similar in our bowels to food allergens? Can it last that long? If yes, it would be almost impossible to find the potential problem foods using the elimination diet.

my little penguin

Staff member
Did you see an allergist or dermatologist for your rash ?
Please see a doctor

True IgE food allergies can cause life threatening reactions to food proteins .
IgE food allergies have symptoms within 2 hours of eating the allergen
This can cause allergic reactions even anaphylaxis.

Most food allergies that only involve one system such as hives are treated with Benadryl for a few days to calm the immune system .

if it’s a more severe reaction /anaphylaxis (Ds has had this to foods)
Epi pen is given at first 9-1-1 is called then Benadryl /steroids at the ER and later taken at home for a few days to calm everything down and keep it calm

food intolerance is not a food allergy - it just means the body for what ever reason doesn’t tolerate a particular food well .
Some are lactose intolerant others may not tolerate a particular food like peppers . This can cause abdominal pain /diarrhea but is not an allergic reaction .

elimination diets are used to isolate food intolerances but are NOT used for true IgE food allergies .

If a IgE food allergy is suspected please see a board certified allergist for testing
Thank you for the detailed answer. Do we know if Crohn's is caused by food intolerance, lgE allergy or neither?
San Diego
Thank you for the detailed answer. Do we know if Crohn's is caused by food intolerance, lgE allergy or neither?
Neither one. The cause of Crohn's is not entirely clear and there may be more than one cause. It primarily appears to be an inappropriate immune response or an over-response to bacteria or other microorganisms in the gut, resulting in chronic inflammation and damage to the gut that accumulates over time.

Diet may play a contributing role in triggering the start of Crohn's but it is almost certainly not an IgE-mediated allergic response or ordinary intolerance to common food allergens. And there are many other risk factors for Crohn's that play a contibuting role in causing Crohn's - genetics, exposure to environmental toxins, disruptions of the population of normal healthy gut bacteria (although that may be an effect of Crohn's rather than a cause), and so on.

Once Crohn's gets going diet may play an important role in helping to manage the disease, but it cannot cure it. An elemental diet can reduce symptoms and even sometimes induce remission, especially in children. And many Crohn's sufferers can identify "trigger foods" that can bring on an attack of symptoms. But those trigger foods vary a lot from patient to patient, and, again, are not known to be inducing a true food alergy.
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