Viral Upper Respiratory Infections (Colds and Influenza) and Essential Oil Monoterpenes
A standardized combination of eucalyptus oil plus two other essential oils has been studied for effectiveness in a variety of respiratory conditions, including cold and flu. This combination therapy contains cineole from eucalyptus, d-limonene from citrus fruit, and alpha-pinene from pine. Because these oils are all in a chemical family called monoterpenes, the treatment is called “essential oil monoterpenes.”
Effect of Essential Oil Monoterpenes on Viral Upper Respiratory Infections (Colds and Influenza)
Essential oil monoterpenes are thought to help by thinning mucus.
Research Evidence on Essential Oil Monoterpenes
Numerous double-blind trials have found essential oil monoterpenes to be effective when taken orally for acute bronchitis, chronic bronchitis, sinus infections, and other respiratory conditions, in both adults and children.68-72,101 Cineole alone at a dose of 200 mg three times daily showed benefit in a double-blind, placebo-controlled study of 152 people with cold symptoms.150 And a second study involving 150 subjects also demonstrated favorable results of cineole compared to a combination of five other herbal products.168
How to Use Essential Oil Monoterpenes
In studies, this essential oil combination was taken at a dose of 300 mg three to four times daily.
Side Effects and Warnings
Other than minor gastrointestinal complaints, no side effects have been reported with this essential oil combination. However, be advised that essential oils can be toxic if taken in excess. Maximum safe doses in young children, women who are pregnant or nursing, and individuals with severe liver or kidney disease have not been established.
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