Catnip has traditionally been used as a home remedy to treat a variety of human illnesses.
Catnip has been prepared and used by people for many years. It was originally used a tea, juice, tincture, infusion, and poultice and has been smoked and chewed. It fell out of favor with the development of more effective drugs. More recently, it has been used by people for its hallucinogenic effects.
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Other uses for catnip have been as a cold remedy, for hives, as a diaphoretic (induces sweating), a refrigerant (cools the body), and an anodyne (relieves
pain) (5,9,18). It has also been used as a tonic for pains and rheumatism, as an infusion for whooping cough and measles, a tea for asthma, yellow fever, scarlet fever, smallpox, and jaundice, and has also been smoked to relieve respiratory ailments
—Catnip Its uses and effects, past and present.
A more recent study investigated
the chemical composition and pharmacological basis for traditional use of essential oil of Nepeta cataria L. (Limiaceae) (Nc.Oil) in gastrointestinal and respiratory disorders.
and concluded
These data indicate that Nepeta cataria possesses spasmolytic and myorelaxant activities mediated possibly through dual inhibition of calcium channels and PDE, which may explain its traditional use in colic, diarrhea, cough and asthma.
—Chemical composition and mechanisms underlying the spasmolytic and bronchodilatory properties of the essential oil of Nepeta cataria L.