A vial adapter element for use in a drug mixing system including a body, a vial connection port extending from the body, a hollow vial puncturing spike that protrudes into the vial connection port and is in fluid communication with a syringe-adapter-element connection port that extends from the body, and a plurality of resilient tongues spaced around an inner wall of the body, the tongues being located in gaps formed in the inner wall of the body.
