The medicinal part is the bulb.
Flower and Fruit
The peduncles are up to 3 cm long. The flowers are greenish-white, in orbicular umbels, with 6 free flower bracts that are shorter than the 6 stamens. The pedicles are eight times as long as the flowers. The fruit is a thin-skinned capsule. The seeds are black and angular.
The flowers are in globular umbels, before blooming in membranous sheaths.
Leaves, Stem, and Root
The plant is perennial or biennial. There are many varieties and can be compressed-globose, ovate, or oblong. Most varieties have secondary bulbs. Leaves are shorter than the peduncle, tubular or swollen, and blue-green. There is a hollow scape, which is gray-blue, expanded, and bloated below the middle.
Central Asia is considered to be the region of origin. Onion was introduced to the Mediterranean and is cultivated worldwide.
Onion consists of the fresh or dried, thick and fleshy leaf sheaths and stipules of Allium cepa.
Actions & Pharmacology
Alliins (alkylcysteine sulphoxides): in particular allylalliin (allyl-L-(+)-cysteine sulphoxide) and its gamma-glutamyl conjugates, that in the course of cutting up either the freshly harvested bulbs or those that have been already dried and then re-moistened, are transformed into the so-called alliaceous oils.
Fructosans (polysaccharides, 10-40%)
Saccharose and other sugars
Flavonoids: including quercetin-4′-O-beta-D-glucoside (spiraeoside)
The thiosulphinate exhibits an antimicrobial effect, and is effective against Bacillus subtilis, Salmonella typhi, Pseudomonas aeroginosa and Escherichia coli.
Lipid and blood pressure-lowering effect
Certain constituents function similarly to those in garlic, although this is not yet clinically proven.
Inhibits thrombocyte aggregation
Dimethyl and diphenylthiosulphinateboth retard thrombocyte biosynthesis using thrombase stimulation.
Antiasthmatic and antiallergic effect
Guinea pigs sensitized using ovalbumin were protected from asthma attack through the oral administration of onion juice. Administration of an ethanol onion extract significantly reduced allergy-induced bronchial constriction in asthma patients.
Indications & Usage
Approved by Commission E:
- Loss of appetite
- Dyspeptic complaints
- Fevers and colds
- Tendency to infection
- Inflammation of the mouth and pharynx
- Common cold
In folk medicine, the drug is administered internally for whooping cough, asthma, tonsillitis, and angina. Onion has been used to stimulate gallbladder functions, for digestive disorders with bloating, flatulence, and colic pain, for dehydration, as an aid at the introduction of menstruation. Onion is also used for ascariasis, high blood pressure, arteriosclerosis and in the treatment of diabetes. Externally the drug is used for insect bites, wounds, light burns, furuncles, warts, and in the after-care of bruises.
Onion preparations are used for dyspeptic conditions, respiratory conditions, wounds, pain, and for malarial fever.
Preparations are used for worm infestation, fungal, and bacterial infections.
Allium cepa is used for acute inflammatory illnesses, pain syndrome, and flatulent colic.
Precautions & Adverse Reactions
No health hazards or side effects are known in conjunction with the proper administration of designated therapeutic dosages. The intake of large quantities can lead to stomach complaints. Frequent contact with the drug leads on rare occasion to allergic reactions (hand eczema).
Mode of Administration
Cut onions, pressed juice from fresh onions and other oral galenic preparations.
Onion oil maceration: same as garlic maceration drug extract 1:1.
Old recipe: Siripus Cepae: freshly grated onions 15 g; water 60 ml; ethanol 90% (V/V) 15 mL; saccharose 150 g; the ethanolic extract is boiled with the saccharose.
Popular: pressed juice and onion syrup: made of 500 g onions, 500 g water, 100 g honey, and 350 g sugar.
Onion tincture: 100 g minced onions in 300 g ethanol 70% macerated for 10 days.
Raw drug is used therapeutically.
Externally the juice is spread or laid on as a poultice or in slices.
Internally: onion tincture 4 to 5 teaspoonfuls daily; onion syrup 4 to 5 tablespoons daily.
Average daily dose: 50 g of fresh onions or 20 g of dried drug.
5 drops, 1 tablet, 10 globules every 30 to 60 minutes (acute) or 1 to 3 times daily (chronic); Parenterally: 1 to 2 mL 3 times daily sc; Ointment 1 to 2 times daily (HAB1)