The effects of catnip on humans have not been widely documented by modern medical science, but both European and American folk traditions have assigned this herb several healing properties. One of the main effects of catnip on humans is said to be a sedative effect. Traditional folk medicine typically maintains that a small dose of catnip infused in a tea or ingested as a dietary supplement can soothe insomnia. The herb has also been traditionally used to treat cold, flu, asthma, bronchitis, and other respiratory ailments, and is said to relieve stomachache and other digestive complaints. Both modern physicians and traditional healers recommend that this herb not be administered to pregnant women, as it could contribute to loss of the fetus.
While some say that smoking the herb catnip can lead to feelings of euphoria in humans, most doctors don't believe that this is true. It is believed, however, that the sedative effects of catnip on humans can help to ease frayed nerves and anxiety in small dosages, or induce sleep in larger doses. Doctors and herbalists think that the herb catnip contains a compound known as nepetalactone, which may be responsible for the relaxing and sedative effects of catnip on humans.
In 18th-century Ireland, the herb catnip was often administered to ease respiratory congestion and enhance ease of breathing. The Irish also used this herb as a treatment for delayed onset of menarche, or first menstruation, and as a diuretic to stimulate the passage of urine. Some historical documentation indicates that the herb was administered as a means of inducing abortion in centuries past. Modern medical science has documented the herbs abortifacient properties, and most doctors believe that the herb can lead to uterine contractions and miscarriage in pregnant women.
In traditional Appalachian culture, the herb catnip was often administered as a treatment for stomach upset. It is believed to be a very effective remedy for the symptoms of irritable bowel syndrome. It may help to ease digestion and intestinal cramps. It has been used to relieve diarrhea, and is also seen as an effective remedy for painful intestinal gas.
The additional effects of catnip on humans may be somewhat analgesic. Many believe that the herb can be chewed to relieve the pain of toothache. It has also been administered as a headache remedy.
Catnip is also believed to help stop bleeding and contribute to the healing of wounds, and can be topically applied for that purpose. Most medicinal preparations make use of the leaves and flowers of the plant, but some herbalists believe that the plant's roots can cause irritability.