Fish oil

Packed with omega-3 essential fatty acids, fish oil can help alleviate asthma and allergy symptoms. Several manufacturers make orange-, peach-, and other fruit-flavored fish oil supplements for kids or others who don’t like fish or don’t want to swallow capsules.
Recommended dose: 1–2 grams daily.

Garlic

The antioxidants and sulfur found in garlic make it a great choice for reducing allergies and asthma symptoms and naturally boosting the immune system. Garlic can be consumed raw, cooked, or added to recipes. Look for odor-free garlic supplements at your natural products store.
Recommended dose: The amount of garlic per supplement varies and is stated on the container; a general recommendation is 1 gram daily.

“Green” drinks

Made from spirulina, wheat and barley grasses, and a variety of fruits and vegetables, green drinks are filled with powerful antioxidants and other nutrients that can help detoxify the body. Detoxification can ease allergy symptoms, as well as fatigue, skin rashes, constipation, and other symptoms, by helping to flush out toxic buildup in the body. Fresh and powdered green drinks are available at most natural grocers.
Recommended dose: Follow label directions.

Quercetin

This bioflavanoid is another powerful and natural antihistamine, particularly when taken in conjunction with vitamin C. Quercetin is found in many fruits and vegetables, such as apples and onions, and is also available as a supplement.
Recommended dose: 1–2 grams twice daily with meals.

Vitamin C

Taken in high doses (see recommended dose), vitamin C can reduce allergy symptoms by inhibiting the release of histamines in the body.
Recommended dose: 2–4 grams twice daily with meals.