The HyperVent bag is designed to facilitate the treatment of hyperventilation and replace the paper bag currently used. It comprises a housing with integral mouthpiece ensuring it is easy for the patient to hold. This is in-turn connected to a strong plastic bag. Unlike paper bags the HyperVent bag overcomes the disadvantages which may include the danger of hypoxia, inhalation of foreign bodies and potential source of infection. It also does not disintegrate with use and is medically clean.