vasodilation ,  flushing , and  tachycardia . [9]  Tadalafil inhibits PDE11 more than sildenafil or vardenafil. [9]  PDE11 is expressed in  skeletal muscle , the  prostate , the  liver , the  kidney , the pituitary gland , and the  testes . [9]  The effects on the body of inhibiting PDE11 are