There would be few kitchens that don't have onions in the pantry yet the medicinal properties of this common vegetable are relatively unknown by most people.
The onion is anthelmintic, antiseptic, stomachic, diuretic, antispasmodic, expectorant, carminative and tonic. A decoction or extract made from the onion and the juice are most commonly used as an expectorant or diuretic but have also been used during the ages for the other actions listed above.
Because of its antiseptic properties the onion has been used to treat putrefactive and fermentation processes of the gastrointestinal tract and it's said to lower blood pressure and strengthen the heart. In fact, years ago an elderly herbalist told me that a boiled onion taken every day will help lower cholesterol.
To relieve gas pains and heartburn thinly slice half an onion and eat with bread. For hoarseness and coughs, take onion juice mixed with honey, and infected wounds can be treated by applying onion juice.
Adult doses for onion preparations:
Juice: 1 teaspoon three or four times a day
Cold extract: Soak a chopped onion in 1 cup water for 24 hours and strain. Take ½ cup a day.
Decoction: Chop a medium-size onion and boil in 1¼ cups water until the liquid is reduced to 1 cup. Take 1 tablespoon several times a day for a few days.