Also called by its Chinese name, yin yang huo, horny goat weed has been used ... Icariin also inhibits PDE5 (phosphodiesterase type 5), which is how drugs like Viagra or Cialis work.

In traditional Chinese medicine, epimedium is believed to tonify the kidney by strengthening kidney yang, dispelling wind and eliminating ... it should not be used in cases of hyperactivity of fire ...