Every year, more than 50 million Americans suffer from allergies, according to the Centers for Disease Control and Prevention. Triggers can cause sneezing, coughing, runny nose, itchy eyes and many more uncomfortable symptoms.

Natural alternatives boost your body’s defenses against pollen and other allergens without unwanted chemicals. Get a leg up before allergy season begins by stocking your medicine cabinet with these natural supplements.

Quercetin

A plant-based nutrient in the flavonoid family, quercetin delivers powerful antioxidant and anti-inflammatory benefits. Researchers have found that it prevents the production and release of histamine and other substances that can cause allergic reactions, and protects against heart disease and cancer.

You’ll find quercetin in foods such as onions, broccoli, and red- and blue-hued berries like cranberries and blueberries.

Quercetin supplements are available in tablet and capsule formulations. Optimal doses vary by condition, but a common dose is 500 milligrams twice daily. Do not exceed 1,000 milligrams per day, though, as excess quercetin could damage the kidneys.

Vitamin C

Vitamin C is a go-to supplement during cold and flu season, so it makes sense that this immune-boosting antioxidant is also one of the best natural supplements to reach for when seasonal allergies attack.

In addition to finding this well-known vitamin in oranges and other citrus fruits, you’ll also get hearty doses from red bell peppers, broccoli and strawberries. However, experts suggest that to lower histamine levels in the bloodstream (and successfully reduce allergy triggers), you’ll need a dose of about 2,000 milligrams per day—much more than you’re likely to get from diet alone.

Vitamin C supplements come in a wide variety of formulations, including capsules, tablets, powders and the latest—a spray.

Probiotics

Research suggests that in addition to keeping your digestive system healthy, probiotic supplements can also minimize allergy symptoms. Studies show these beneficial bacteria may even reduce a person’s risk for developing allergies in the first place.

In fact, an analysis and review published in a 2016 issue of the American Journal of Rhinology & Allergy concluded that probiotics diminished seasonal allergic rhinitis. One of the most effective bacterial strains, according to study authors, was Lactobacillus paracasei.

Most probiotics on the market contain several strains from the well-studied Lactobacillus and Bifidobacterium species to support both digestive and immune health. You’ll find each included strain spelled out on the supplement’s label or packaging, if you’re curious to know exactly what you’re taking.

Although there is no recommended dose for allergy symptom relief, doctors recommend a daily dose of 1 billion to 15 billion colony-forming units (CFUs) for promoting good intestinal health.

Omega-3s

Likely because of the powerful anti-inflammatory properties of omega-3s, research findings suggest that a diet high in omega-3 fats is associated with reduced hay fever or allergy symptoms.

Increasing the amount of oily fish such as salmon and halibut you eat, and adding flaxseeds and walnuts to your diet, may help, but a good high-potency supplement is even more effective.

Your body needs both eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), so look for supplements containing both of these essential fatty acids. Doses exceeding 3 grams daily should not be taken without the supervision of a health care provider.

Spirulina

Spirulina is a blue-green algae known to boost the immune system, along with a variety of other health benefits. A Turkish study investigated the ability of spirulina to improve symptoms of allergic rhinitis. At the end of the study, the subjects who consumed spirulina (2,000 milligrams per day) had less nasal discharge, sneezing, nasal congestion and itching than the subjects who were randomized to a placebo.

Spirulina is a popular superfood rich in vitamins A and B12 with naturally occurring protein.

Herbal Remedies

Some herbal supplements are known for their abilities to balance the immune system and block the reactions that cause certain allergy symptoms.

Studies have found butterbur leaf extract (Petasites hybridus) to safely and effectively treat patients with seasonal allergic rhinitis; it worked as well as the allergy medications Zyrtec and Allegra in treating symptoms when subjects took 500 milligrams per day for two weeks.

Stinging nettle (Urtica dioica) has been used traditionally to treat a number of conditions, including seasonal allergies. A 2009 study published in the journal Phytotherapy Research found that the anti-inflammatory activities of stinging nettle could relieve allergic rhinitis symptoms. A daily dose of 600 milligrams for one week is recommended.

Astragalus has been touted as an immunity booster and used for thousands of years by Traditional Chinese Medicine practitioners to protect the body against environmental stressors. In addition to its uses in improving energy and preventing colds and upper respiratory infections, a 2010 study found a formulation of astragalus reduced allergy symptoms, including itching, sneezing and runny nose. Take 160 milligrams twice a day for maximum benefits.

NOTE: Herbal preparations aren’t safe for everyone. Talk to your doctor before you begin a new herbal supplement regimen, especially if you are pregnant, breastfeeding or taking any prescription medications.