Botanical Overview
Allium cepa, commonly known as onion or common onion, is a member of the Amaryllidaceae family cultivated worldwide. The bulb is the primary part used medicinally, with occasional use of the leaf. It is a staple culinary and medicinal plant.
Energetics
Onion has a warming temperature and drying moisture quality. Its tastes are primarily pungent and sweet, with an ascending and outward directionality. Tonically, it is considered tonifying and primarily influences the qi aspect of the body’s vital substances.
Primary Actions
- Antimicrobial
- Antioxidant
- Anti-inflammatory
- Diuretic
- Expectorant
- Hypotensive
Indications
Western
- Cough
- Congestion
- Hypertension
- Hyperlipidemia
- Infection
- Digestive complaints
Syndromes
- Cardiovascular risk factors
- Respiratory infections
- Inflammatory conditions
TCM
- Cold phlegm
- Cough
- Nasal congestion
Syndromes
- Wind-cold invasion
- Phlegm accumulation
Ayurveda
- Cold disorders
- Kapha imbalance
- Digestive weakness
Syndromes
- Kapha-related ailments
- Impaired digestion
Unani
- Cough
- Cold
- Bronchitis
Syndromes
- Balgham (phlegm) disorders
- Sardi (cold) ailments
Constituents & Mechanisms
Onion contains flavonoids (notably quercetin), organosulfur compounds, selenium, and vitamin C, which contribute to its antioxidant, anti-inflammatory, and antimicrobial effects.
Dosage & Preparations
- Fresh bulb eaten raw or cooked
- Onion juice 5-10 mL 1-3 times daily
- Tincture 1:5 in 40% ethanol, 2-5 mL 1-3 times daily
- Decoction 2-4 g 1-2 times daily
Safety & Contraindications
Generally safe when consumed in culinary amounts. May cause gastrointestinal irritation and allergic reactions in sensitive individuals. Use caution with blood-thinning medications due to potential increased bleeding risk. Limited data exist on safety in pregnancy; excessive use should be avoided. Contraindicated in persons with allergy to Allium species and bleeding disorders.
Astrological Correspondences
No well-supported planetary or elemental rulers identified from credible traditional sources.
Selected References
- Allium cepa – Onion, Plants For A Future Database
- Herbal Medicinal Products Committee Assessment Report on Allium cepa, European Medicines Agency, 2015
- Phytochemical and pharmacological review of Allium cepa, Rani R & Naga SS, 2017
- Allium cepa L., The Ayurvedic Pharmacopoeia of India, 2001
- Medicinal use of onion in Unani medicine