Passionflower contains tranquilizing chemicals, so it is commonly used as a sedative to relieve nervous tension and insomnia. It is also useful as a muscle relaxant and as a liver tonic.

Topically it is useful for treating boils, wounds, and earache
Formerly approved as an over-the-counter sedative and sleep aid by the US Food and Drug Administration.

Most research on passionflower has been done in animal studies related to its antispasmodic and sedative properties. Studies show that extracts of the herb inhibit fungi and bacteria. Studies also indicate that the herb (or its extracts) relieves spasms, has a sedative effect, allays anxiety, and lowers blood pressure.

In European herbal medicine, passionflower products are used for nervous tension, especially in sleep disturbances or anxiety arising from restlessness. Recent research on passionflower indicates that several chemical components, probably flavonoids, act together to cause these effects.