Compounds of 効く

• 効く
  (v5k,vi) (1) to be effective
  to show effect
  (2) to do its work
  to carry out its function well
  (3) to be possible to use
  (P)
• 目が効く
  (exp) to have an eye for
• 薬が効く
  (exp,v5k) to have medicine be effective
• 割引が効く
  (exp,v5k) to be able to get a (type of) discount
• 良く効く薬
  (n) very efficacious medicine