Sir, I read with interest a recent paper on the dental management of heroin and methadone users.1 In this article, a patient was described as having a paradoxical reaction to treatment under intravenous sedation (IVS) with midazolam. Treatment under inhalation sedation (nitrous oxide and oxygen) alongside behavioural management techniques was successfully carried out at subsequent dental visits. Inhalation sedation (IHS) may be used to facilitate dental treatment in both adult and paediatric patients. The low blood solubility of nitrous oxide means it brings about a rapid sedative effect and quick recovery. As a sedative agent, nitrous oxide (N2O) and oxygen has a wide margin of safety. It is excreted almost unchanged by the lungs and its low potency is reflected by its high minimum alveolar concentration (MAC) of 105%. There are, however, contraindications to its use, such as nasal obstruction and poor patient cooperation.2

IHS with nitrous oxide has been successfully used in patients undergoing dental extractions, with a statistically significant reduction between pre- and post- operative modified dental anxiety scale (MDAS) values in patients with moderate to severe anxiety.3As such an invasive procedure is tolerated well under IHS, should this provoke more clinicians to consider its use where sedation is required in adult patients?