Codeine overdose
A pathologist told the court that toxicology results showed that Mrs Gascoyne had died as a result of a codeine overdose which had depressed her central nervous system and caused her to fall into a coma before stopping her breathing.
Toxicology results showed that Mrs Gascoyne had 8,619 mg per ml in her system, as well 114 mg per ml of morphine.
The normal range for codeine to treat pain is between 30mg per ml to 340 mg per ml. Mrs Gascyone had over five times the lethal range of the prescription drug in her system at the time blood and urine samples were taken for the toxicology report.
The pathologist told the court that Mrs Gascoyne had a "massive, massive amount" of the drug in her system. She said codeine has a lethal range of "anything over 1,600 mg per ml."
She said: "It was a massive dose. She also had high levels of morphine just about in the lethal range that is between 50 to 40,000 mg per ml, she had 114 mg per ml.
"Taking that into account, there are no two ways about it despite everything she had going on she died due to the effects of the codeine.
The way it causes death is that it depresses the respiratory system and eventually the cardiac system and central nervous system which makes the person drowsy and they go into a coma.
Robert Forrest, professor of forensic chemistry at Sheffield University, said a codeine overdose would take between six and eight hours to kill someone,
in overdose, suppression of normal breathing, and risk of respiratory arrest (when you stop breathing altogether
There is a greater risk of overdose and death if you are mixing opiate painkillers with other drugs that suppress breathing such as
alcohol,
benzodiazepines (like diazepam or Valium), and/or other opiate drugs. There's a particular risk of death due to inhaling vomit – because opiate painkillers can sedate you, can add to the risk of vomiting, and can stop you from coughing properly. The vomit blocks the airways or later leads to pneumonia