What are Histamine Reactions?

Histamine reactions are a defense mechanism employed by the immune system to protect the body from allergens. When the immune system comes in contact with an allergen, it sends out the chemical histamine. Histamine reactions may include nasal swelling, rashes, and itchy eyes. Severity of a histamine reaction can range from mild to severe. Severe allergic reactions may require medical attention.

When a foreign substance or allergen enters the body, the immune system triggers production of immunoglobulin E, also known as IgE antibody. The antibody pairs up with white blood cells in the bloodstream and rushes to the foreign substance. For instance, if an allergen is inhaled through the nose, IgE and white blood cells will rush to the nose.

When IgE and white blood cells reach the allergen, mast cells are alerted to produce histamine. Histamine causes allergy symptoms such as sneezing, watery eyes, and skin rashes. When too much histamine is released or if the body is sensitive to histamine, a severe allergic reaction could occur.

The effects of severe histamine reactions may include shortness of breath, labored breathing, or swelling. In a small number of cases, severe histamine reactions may lead to anaphylaxis, or anaphylactic shock. Anaphylactic shock is a combination of histamine reactions and lung restriction. Blood pressure drops and breathing is impaired or may become impossible.

Anaphylactic shock can be life-threatening if medical treatment is not administered within a short time. Treatment for a severe histamine reaction such as anaphylactic shock may include self-administered epinephrine shots. Epinephrine shots require a medical prescription. Not all histamine reactions will require medical attention — in many cases, over-the-counter medications or avoidance may be enough to treat mild symptoms.

A histamine reaction can be triggered by environmental substances, animals, and foods. Common environmental allergens include dust, pollen, and mold. Three animals that commonly cause allergic reactions include dogs, cats, and horses. Adults and children also may suffer from food allergies that cause histamine reactions. Peanuts, milk, and strawberries are of particular concern in children.

Symptoms of histamine reactions may be seasonal or situational. Seasonal allergies include pollen and ragweed. Situational allergies may include animal or food allergies. If the histamine reaction to seasonal or situational allergies are severe, doctors may suggest avoidance along with prescribing emergency medications, such as an epinephrine shot. If a shot is used, the patient must immediately be taken to a hospital emergency room for medical attention.

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Post 4

Has anyone here ever heard of a person being allergic to cold temperatures? My friend has this condition, and it is very bizarre.

If she goes outside in cold weather, she breaks out in hives and itches all over, especially while she is warming up inside. Also, if she eats ice cream, her lips will swell. I have even seen her hands swell while she is holding a glass of iced tea.

She tries to avoid the cold as much as possible, but during winter, she has to go out in it to get to work. Her doctor put her on a daily antihistamine, which she takes before leaving the house to prevent the symptoms.

Post 3

I have only had mild histamine reactions, and most of those were in the form of a red rash. There are only a couple of things that cause this, and since I know what they are, I can avoid them.

One is hay. I used to love playing in the hay in my neighbor's pasture, but I would come home with a raised red rash covering my arms. It would itch a lot, but it didn't hurt or burn.

The other allergen is dogs. I love them, and I own a couple, but when playtime comes, I simply put on a long-sleeve shirt. Then, I can wrestle with them without developing the rash.

The rashes never last for long. I can make them stop itching with hydrocortisone cream, which makes them disappear faster, too.

Post 2

@kylee07drg – I had that test done when I was six years old. I was allergic to quite a few things, and my runny nose was making me miserable.

My doctor decided to start giving me weekly allergy shots. I didn't like needles, but my mom told me they would make the sniffles go away, so I went along with it.

After a couple of months of weekly shots, nothing had changed. My mother let me quit the shots, since they weren't doing any good.

Now that I'm grown, I still deal with allergies every day. However, there are now antihistamines that are supposed to work for twenty-four hours on the market, and I take one every day to control my histamine reactions. They don't totally eliminate my sinus issues, but they definitely have helped.

Post 1

It's crazy how a person can have histamine reactions as a child and then grow up to be totally tolerant of their previous allergen. My body used to react strongly to cats, but now, I can pet one without so much as a sneeze.

I had been having a lot of trouble with my sinuses and watery eyes as a kid, and my parents believed that our new litter of kittens might be to blame. They took me to an allergist, who did a skin prick test.

He put tiny amounts of possible allergens on my back and pricked the area with a needle so they could get inside my skin. The areas that swelled up and turned

red showed that I was allergic to whatever had been placed in those spots.

I showed a strong reaction to cat dander. So, my parents gave the kittens and their mother away. I was sad about it, but luckily, I wasn't allergic to dogs, so they consoled me with a new puppy!

I have grown up to be a dog person, even though I have no histamine reactions to cats now. It's nice to know I can be around someone else's pet cat without having an allergic fit, though.

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