Hyperforin, recently isolated from St. John's Wort, is reported to be inhibitory toward a number of gram positive organisms. The plant has given negative antibiotic tests, but positive results have been obtained also. Among the organisms inhibited are Micrococcus pyogens var. The tannic acid complex was shown to significantly inhibit influenza virus. St. John's Wort Is An Antihelminthic Liquid extract of this herb is effective against dipilidiasis, hymenolepidiasis, and somewhat less effective against ascaridiasis in dogs, without toxicity to the host except at very high doses which have a mild hypotensive effect.
Smaller doses stimulate the cardiovascular system.
Intravenous dosage does not affect the depth or frequency of respiration. Clinical tests have been favorable. Cholagogue Properties Cholagogue activity of St. John's Wort is thought to be due to alkaloids, including nicotinic acid and nicotinamide and other hetereocyclic, nitrogen containing principles. It appeared to act by normalizing glucose metabolism in brain tumor slices, thus inhibiting tumorous growth. Psorospermin from St. John's Wort has antileukemic property.