These are natures very own antibiotics to treat asthma. Onion and garlic stimulate the excretory organs, for assimilation of food to strengthen the lungs. Onions are very rich in a powerful anti-inflammatory compound called quercetin that helps relieve allergies. A prominent researcher Dr. Walter Dorsch, found that onions have a direct anti asthmatic effect due to the presence of thiosulphates that have very active anti inflammatory properties