Natural Cough Remedy: Vitex negundo L.
Vitex negundo, commonly known as the Chinese chaste tree, five-leaved chaste tree, horseshoe vitex, or nisinda, is a 2-5 meters high aromatic shrub with quadrangular, densely whitish, tomentose branchlets. It bears tri- or penta-foliate leaves and has bluish-purple colored flowers (1). Vitex negundo is generally used to treat coughs, asthma symptoms, and other respiratory problems, particularly in South and Southeast Asia.
The Philippine Department of Health has recognized Vitex negundo as an effective, clinically proven medicinal plant in treating respiratory complaints like cough and asthma (2). Butanoic extracts of it significantly inhibit cough reflex in a dose-dependent manner. It contains B-sitosterone, casticin, chrysophanol D, luteolin, and alpha-hydroxybenzoic acid. Vitex negundo inhibits histamine release. Its activities are particularly due to the content of iridoids agnuside, lagundinin, 2’-parahydroxybenzoyl mussaenosidic acid, and the flavonoids casticin and chrysophenol D, which has anti-inflammatory potential. The anti-inflammatory action of Vitex negundo is partly explained by its ability to inhibit chemotaxis, phagocytosis, and complement activation. It has anti-inflammatory properties in acute and subacute inflammation. Anti-inflammatory and pain-suppressing activities of fresh leaves of Vitex negundo are attributed to prostaglandin synthesis inhibition and antihistamine, membrane stabilizing, and antioxidant activities (1).
Extract of Vitex negundo stabilizes mast cells, shows inhibitory effects on immediate hypersensitivity reactions, and exhibits anti-eosinophilic activity, which is considered the underlying mechanism involved in the anti-asthmatic function. Crude extract of the leaves of Vitex negundo in hyperactive respiratory disorders possesses a combination of papaverine-like phosphodiesterase inhibitors and diltiazem-like Ca++ entry-blocking constituents, partly explaining its broncho-dilating effect. Plant extracts exhibit numerous pharmacological actions with multiple mechanisms, which are activated by several different types of compounds (1).
There is considerable ethnomedical and pharmacological evidence that Vitex negundo possesses analgesic, anti-inflammatory, antihistaminic, antibacterial, antioxidant, and broncho-dilating potential. Vitex negundo is extremely relevant in primary care and decreases the frequency and duration of coughing with no serious adverse effects (1).
1. Alegado-Bagaoisan DM, Castro MCR, Purificacion JM. A systematic review on Vitex negundo (NIRPROMP formulations) for the treatment of acute cough of mild to moderate severity in pediatric patients. Acta Medica Philippina 2020; 54(1): 36-43.
2. Dayrit FM, Macahig RS. Encyclopedia of Common Medicinal Plants of the Philippines, Vol. 1. Quezon City: Philippine Institute of Traditional and Alternative Health Care, 2014.