If the patient is particularly nervous about attending the dentist and having treatment, conscious sedation can be offered where nitric oxide and oxygen are inhaled during the treatment. The gas mixture relieves stress and fear but is not a pain control device. Anaesthetic has to be used to control pain. The patient is conscious all the way through the treatment. There are no side effects with the use of conscious sedation and it can be used even if the patient is on other medication. Pregnant women and those suffering from a cold are advised not to use conscious sedation. Once the treatment is over, oxygen is given to the patient to flush the nitric oxide from their body and they are good to go.