A condition listed in the US manual of psychiatric disorders and defined as an absence or lack of any sexual desire and sexual fantasies [in either sex]. Usually it can be mild, but when it becomes severe, it can cause severe distress in the patient and also cause problems with the relationship. The US Federal Drugs Agency has licensed a drug for treatment of this condition but it is not widely accepted as a diagnostic entity in the UK and concerns have been expressed that it might represent an example of a so-called ‘non-disease’, an artificial construct designed as a marketing tool for medication.