To keep your immune system from over reacting, you will first need to figure out just what is causing it to go into overdrive. Here are five immune system stressors that may be contributing to the release of histamines in your body.
Your diet: Adopting an anti-inflammatory diet is one of the first steps to take during allergy season. If you eat foods that are high inflammatory foods, your seasonal allergies can be worse especially if you're already sensitive to a particular food. For me that would be sugar, and that can be a big problem, because I love my sweets. There are two types of foods that can cause an inflammatory reaction that will exhaust your immune system. The first type are the foods you can't digest well; ones you may not even know you have a problem with. The most common food allergies are wheat, milk, eggs, and peanuts. When your body is sensitive to a certain food it puts your immune system into a fight mode so that when seasonal allergies come along it over reacts because it's still in that heightened state from trying to fight off the food allergies. This will cause your allergies to spiral out of control. If you follow a diet that minimizes inflammation in your body and creates little or no stress on your immune system, then your body won't react so violently to external allergies. The second type of inflammation causing foods affect everyone and you don't have to have food sensitivities, and these include saturated fats, processed foods, and heavily refined carbohydrates. Daniel Monti, MD, director of the Jefferson-Myrna Brind Center of Integrative Medicine at Thomas Jefferson University Hospital in Philadelphia and author of "The Great Life Makeover", says to cut out all of these products, especially during allergy season, and instead eat lots of fruits, veggies, and whole (gluten-free) grains. So how can you tell if there are underlying food allergies that are making your seasonal allergies worse? Eliminate one food at a time that you think is causing the problem, let's say for a week or so. Then, on the eighth day, bring that food back into your diet and watch for things like increased mucus, asthma-like symptoms, skin rashes, gas, bloating, heartburn, headaches, fatigue, or mood changes. If you see any of these symptoms, or you just don't feel as well as you did when you were off of that food, eliminate that food from your diet. Keep repeating this process with any other foods you think is causing your problem. You won't see immediate results once you've eliminated a food from your diet, and two to four weeks may pass before you do notice any relief. Also, if you are allergic to the food, you may be able to add it back into your diet once allergy season is over.
Stress: Research has linked overwhelming stress from work, family, money problems, and just the stress of life in general, to numerous chronic health problems and diseases. But, they have also discovered that stress can make your allergies worse, because the hormones and other chemicals released during long periods of stress, causes damage that triggers the immune response. Your body uses nutrients, including antioxidants and vitamins, to keep your bodys' defenses up against stress. But, when stress becomes a constant thing, the body will need more nutrients to keep it going. The more stress we have, the more likely we are to make very poor food choices and not get the sleep we need. When you look at all these factors, it's no wonder our immune systems are off balance! Getting regular exercise, enough sleep, and practicing mind-body techniques like yoga and meditation, will help you to manage the stress you face every day. Taking a daily multivitamin and eating five to nine servings or more of fruits and veggies a day will also help your immune system to build up the supply of nutrients it needs to fight stress.
Your home: Just like you, there are many of the things that trigger your allergies that consider your home a sanctuary. There are an unbelievable 52% of US households that have at least six detectable allergens, all of which can find their way into your body, this is stated in a report from the Journal of Allergy and Clinical Immunology. Some of those allergens that can be detected include animal dander, dust mites, mold, scented candles, cleaning products, and cigarette smoke. I rather imagine these allergens don't spark much of a histamine reaction in a healthy immune system, but if your immune system is hypersensitive, like it is when you have an autoimmune disease, they'll set off a number of alarming symptoms. Luckily, you can eliminate those possible reactions by doing a few simple things. The first thing you can do is to use a saline nasal rinse once a day, maybe twice if you're have a rough day. A saline nasal rinse will flush out any allergens in your nasal passages. You can purchase a nasal rinse in any drugstore or you can make your own by adding a teaspoon of salt and a pinch of baking soda to a quart of boiling water. Let the solution cool to body temperature before you put it in a neti pot to flush your nose. If the rinse burns, then you should add more baking soda. There are four other common household irritants that can compromise your immune system.

Dust Mites: The key to controlling this little microscopic creatures is to give them fewer places to live. If it is possible, you might want to consider replacing your carpet with hardwood and you also might want to think about limiting upholstered items and fabric hangings like wall tapestries or drapes. To kill dust mites you will want to enclose your pillows, mattresses, and box springs in allergen proof covers, wash bed sheets, mattress pads, and blankets in 130 degree water every week. I also put all my pillows, bed and throw, in the dryer for about 45 minutes, once a week, the heat is what kills them. Now here's a trick I didn't know about, if you have stuffed animals, and who doesn't, every six weeks you will need to wash them in hot water or you can stick them in plastic bags and freeze them overnight to kill off the mites.

Animals: Pets are one of the largest contributors to household allergens, including proteins found in their dander, dead skin flakes, urine, and saliva. Cats are actually worse than dogs because their dander is lighter and it clings to everything, which makes it more likely to breath in and cause your immune system to "attack" it. The thing about your pets dander is that it can linger a lot longer, so by swapping your carpet for hardwood, keeping your pets off upholstered furniture, and investing in a HEPA air filter, which reduces dander in the air and can make a difference

Mold: One of the best ways to reduce mold in your house is to keep the temperature around 68 degrees and the relative humidity about 35 percent; you can pick up a humidity gauge to monitor this. Mold tends to grow in potting soil, especially if it's too moist, keep all indoor plants on the dry side and ban plants from the bedroom, where you spend up to a third of your time. You might want to place a dehumidifier in damp basements or crawl spaces during the summer, which can improve overall air quality throughout the entire house. Now for the last of the household allergens that can send your immune system into overdrive,

Airborne chemicals. Try using natural cleaning products or better yet make your own. Here are some of the homemade products I use: for my furniture I mix 1/4 c. of vinegar to 3/4 c. oil (olive, vegetable, or lemon), for a general cleaner I will sprinkle plain baking soda on the surface and use a wet sponge or cloth to clean, after cleaning, rinse out your sponge or cloth and wipe the surface until all baking soda residue is gone. I use this on my tubs and sinks as well instead of soft scrub. For my windows I mix 1/2 c. rubbing alcohol with 1 c. of vinegar in a spray bottle and then I fill the bottle with water until it's full. You will also want to avoid synthetic fragrances in scented candles, detergents, and deodorant; and if you smoke or live with smokers, this would be a good time for everyone to stop.
Antibiotics: You use antibiotics to treat bacterial infections like strep throat, urinary tract infections, and some sinus infections, antibiotics succeed when it comes to fighting bacteria, but they can wreck havoc on the good bacteria that live in your intestines. Did you know that 70% of your immune system is stimulated by the good bacteria in your intestine? If you have taken antibiotics any time for anything there is probably a good chance that your immune system is imbalances. Taking a probiotic daily will help in countering any loss of healthy flora, but be sure that you find a brand with self-stable lactobacillus, while you're on antibiotics and for at least three months after you finish your prescription. There is research that supports this regiment: A study published in Clinical and Experimental Allergy found that people with grass pollen allergies who took probiotics experienced fewer allergy symptoms than those who didn't. You might even want to consider taking a probiotic year round for your overall gut health, especially if you're middle-aged or older.
The outdoors: I don't know anyone who has seasonal allergies, who spends much time outside during the allergy season. There are many different types of pollen that are the obvious offenders but there are also other irritants like pollution and diesel fumes, that can act like a chronic irritant on the mucous membranes of the nasal passages and the body has to work harder to eliminate them. To deal with these outdoor irritants, reach for your saline nasal rinse. Here's something to think about if you are wanting to get out of the house during the seasonal allergy time. Most plants pollinate in the morning, which is why the pollen count is higher during the first part of the day. So the best time to do that gardening, running errands or exercising would be in the afternoon. But better yet, a good time to go out is right after a storm. After all, I'm sure that many of you have been told that rain cleans the air and not only that but the pollen count is almost zero. While you can't expect it to rain every day to wash away the pollen, the next sure way to get your seasonal allergies under control is to tend to your immune system. Strengthen it with good healthy food and plenty of sleep, but the most important thing is to give it a rest. If your immune system isn't always rushing around trying to keep you healthy, there is a good chance it won't care about a little nose full of pollen and mold spores.
I know from experience just what it's like to have allergies and a compromised immune system. I had never had allergy problems until I was in Austin, Texas and got what they call cedar fever, another words I was allergic to the cedar pollen. I became so sick that I was taken to the hospital because I had stopped breathing because I was so congested. Anyway, after I got over that I ended up having allergic reactions to everything that pollinates, trees, flowers, bushes, anything. I also found out that my fibromyalgia will trigger sinus infections and what feels like an allergic reaction to something. Because I have four autoimmune diseases my immune system is in a constant state of alert and rarely gets a break. It takes me several months to get over an allergy attack where it would take someone with a normal immune system a couple of weeks.
I hope you find this information helpful.