The first synthetic opioid, it was originally synthesized by Charles Wright at St. Mary's Hospital, London in 1874 but was not used as a medicine until marketed from 1898 under the trade name Heroin (Heroïne) by Bayer. Together with aspirin, it helped to make Bayer's fortune. Its synthesis was made illegal in the USA in 1924. Use has considerably reduced in Britain, the main legal medicinal market during 2005 due to supply problems, and is projected not to return to previous levels simply because it is more expensive than morphine for most indications.
By the early 1980's British doctors were writing just under 99% of the world's prescriptions for medicinal diamorphine and consuming 95% of the worldwide legally produced annual quantity of about 300 kg of diamorphine (United Nations International Narcotic Control Board, 1990). There is clinical trial evidence that 5mg iv gives more prompt pain relief than 10mg morphine in myocardial infarction but this may not be of clinical significance.
Where a high solubility opioid is required.
IV or Epidural
Its use even for medical purposes is illegal in many countries.
Cautions and Interactions
Diamorphine is the diacetylated form of morphine. Being more soluble than morphine, it readily crosses the blood-brain barrier where it is subsequently hydrolysed to 6-monoacetylmorphine (6-MAM) and morphine. Hydrolysis to 6-MAM occurs rapidly and measurement of 6-MAM in autopsy toxicology is a method for confirming ante-mortem diamorphine use.