Intranasal diamorphine as an alternative to intramuscular morphine: pharmacokinetic and pharmacodynamic aspects.

Diamorphine is a semisynthetic derivative of morphine that is currently licensed for use in the treatment of moderate to severe acute pain, administered by the intramuscular, intravenous or subcutaneous routes. It is highly water-soluble and has a number of properties that render it suitable for administration via the nasal route. Administration via the intranasal route is well described for other drugs, but has only recently been evaluated in a clinical setting for diamorphine.