RECORD OF INVESTIGATION INTO DEATH (WITHOUT INQUEST)
Coroners Act 1995
Coroners Rules 2006
I, Stephen Raymond Carey, Coroner, having investigated the death of:
Timothy Graham Davis
(a) The identity of the deceased is Timothy Graham Davis (Mr Davis) who died on 1 August 2009 at Southern, Tasmania.
(b) Mr Davis was born in Australia on 21 November 1973 and was aged 37 years.
(c) Mr Davis was separated from his wife and unemployed at the time of his death.
(d) Mr Davis died as a result of combined drug (fluoxetine, olanzapine, mirtazapine, methadone, oxycodone and diazepam) intoxication.
CIRCUMSTANCES SURROUNDING THE DEATH:
Dr Richard Jackett, General Practitioner reports that Mr Davis had been a patient of his practice since 9 October 2006. Dr Jackett notes that Mr Davis consulted him on 3 September 2007 advising of a previous diagnosis of Bipolar Disorder for which he had been taking Zyprexa and Temazepam. Dr Jackett referred him to Southern Mental Health, who together with Dr Jackett oversaw his treatment for the next 23 months. As a result of a review by psychiatrist, Dr Ashley, Mr Davis’ medications were altered in April 2009. He was prescribed Fluoxetine 70mg/day, Olanzapine 10mg twice daily, Diazepam 20 mg/day and Mirtazapine 15 mg daily. Medications at the time of his last consultation also included Keflex (anti-biotic), Nexium (a proton pump inhibitor used for gastro-oesophageal reflux usually) and Panadeine Forte (analgesic with codeine).
Mr Davis presented to Dr Jackett on 27 July and 28 July 2009 accompanied by his neighbour, Mrs Annette Jenkins. Mr Davis requested assistance in managing an addiction to Oxycontin. Mr Davis advised Dr Jackett that he had purchased Oxycontin "on the black market over a period of 12 months and used about 80mg per day". Mr Davis reported that this use was causing him financial difficulties and had caused him to self harm via cutting his forearms several days prior.
Dr Jackett offered Mr Davis inpatient referral for detoxification however Mr Davis declined.
Dr Jackett consulted the Alcohol and Drugs Unit at St John’s Park and the Pharmaceutical Branch of the Health Department to organise and discuss appropriate treatment for Mr Davis. He subsequently referred Mr Davis to Dr Richard Bourke, General Practitioner and Mr Daniel Steppings, Alcohol and Drug Services, St Johns Park.
Dr Richard Bourke, General Practitioner first consulted Mr Davis on 30 July 2009. This referral was made by Dr Jackett with a view to starting Mr Davis on the methadone program. Dr Bourke reports that Mr Davis told him that "he started using illicit oxycontin approximately twelve months earlier and was using on average 80 mg per day. He … was $3,000 behind in his rent. He was the sole parent to his fourteen year old daughter". When seen on 30 July 2009 Mr Davis requested to be put on the methadone program. Dr Bourke formed the view that Mr Davis was "keen to start making some changes in his life and get himself back on track". On 31 July 2009 Dr Bourke obtained permission to prescribe methadone and provided Mr Davis with a script for valium to assist with withdrawal symptoms. Contact was made with the Rosetta Pharmacy to request that they dispense the prescription. Mr Davis was started on 25 mg per day to be increased to 30 mg per day from 5 August. Dr Bourke planned to review Mr Davis in ten days.
Dr Bourke noted that Mr Davis was also being treated for Bipolar Disorder and that he was "on olanzapine, fluoxetine and mirtazapine".
Mary Sharp, Chief Pharmacist, Department of Health and Human Services reports that Mr Davis first commenced on the Pharmacotherapy program and was prescribed methadone syrup in April 2000. He continued to receive methadone until September 2001. There are no further records of Mr Davis receiving schedule 8 (narcotic) medications until July 2009 when Dr Richard Bourke made application for authority to prescribe methadone syrup as part of the pharmacotherapy program. Mr Davis commenced on the program and was first "dosed" at the Rosetta Pharmacy on 30 July 2009. Mr Davis received further doses on 31 July and 1 August again at Rosetta Pharmacy and was not provided with any "take-away" doses.
Enquiries by Mary Sharp of the Rosetta Pharmacy indicate that on 30 July 2009 Mr Davis was dispensed prescriptions for fluoxetine and olanzapine as prescribed by Dr Richard Jackett together with prescription for diazepam as prescribed by Dr Bourke. A prescription for mirtazapine was supplied on 18 May 2009 as prescribed by Dr Jackett. Ms Sharp notes that "supply … from other pharmacies may have occurred but we don’t have access to information indicating if that did occur".
Mr Davis’ mother, Irene Lomas states that Mr Davis had been a cannabis user since his mid teens. She notes that Mr Davis took full custody of his daughter Shai Davis in January 2008 and that Shai lived with Mr Davis full time. She spoke to Mr Davis on 30 July 2009 at approximately 6.30pm at which time he appeared to be in"good spirits".
Angela Davis, Mr Davis’ sister, confirmed that Mr Davis was a regular cannabis user and that he "would take Oxycontin". She refers to an episode in March 2009 where Mr Davis overdosed on Oxycontin and an Ambulance was called. Mr Davis was not transported to hospital. Ms Davis last saw Mr Davis on 30 July 2009 at approximately 7.30pm at which time Mr Davis told her that he was starting the Methadone Program and "seemed excited about not having to pay for drugs anymore".
Ms Annette Jenkins was Mr Davis’ neighbour and had known him for approximately six months. On 31 August 2009 she sent a message to Mr Davis at approximately 8.30am to check if he was ready to go to the pharmacy to collect his methadone dose. They attended the pharmacy together at approximately 9.00am. They returned to Ms Jenkins’ home and had coffee and something to eat. Ms Jenkins notes that Mr Davis also "took his valium that day just after his dose" and that he was "drowsy because of it" and "went back home and went to bed". At approximately 4.00pm Ms Jenkins went to Mr Davis’ home. She noted that he looked as though he had just got out of bed. She did not trust him to cook so prepared a meal for both of them.
On 1 August 2009 Ms Jenkins saw Mr Davis for coffee at her home prior to leaving for the pharmacy. She states that he "was in a good mood and more alert than normal". On their return they again had coffee at Ms Jenkins home and she notes that "he kept going back over to his place, this was when we came back from the chemist. Each time he came back to my place his condition was getting worse. The final time he came back over he was incoherent. He kept falling off his seat…..He knocked his coffee off the table". Ms Jenkins took Mr Davis home and offered to make him dinner and Mr Jenkins advised her he would come to her home at 3.00pm. When Mr Davis did not attend Ms Jenkins went to his home and when she received no response to knocking and calling him she called Police.
Tasmania Police Officers attended at approximately 3.35pm and spoke to Ms Jenkins who indicated her concern for Mr Davis reporting him as being on the methodone program and that he had been unwell when she last saw him. Entry was forced via the rear door to the unit. Mr Davis was found, deceased, lying on the edge of a bed in the main bedroom of the unit. He was fully clothed. A quantity of medication including olanzapine, diazepam, panadeine forte, mirtazapine, cephabell were found in the unit together with a smoking device accompanied by cannabis. There were no signs of forced entry or a struggle. No note or message was found. Mr Davis was transported to the Royal Hobart Hospital.
Andrew Griffiths, Forensic Scientist, Forensic Science Service, Tasmania carried out toxicology testing on post mortem blood and reports the presence of:
- methadone (analgesic and central nervous system depressant) at a therapeutic level 0.3 mg/L
- oxycodone (semisynthetic analgesic) at a therapeutic level of 0.04 mg/L
- fluoxetine (anti-depressant) at a greater than therapeutic level of 0.6 mg/L
- mirtazapine (anti-depressant ) at a therapeutic level of 0.1 mg/L
- olanzapine (antipsychotic agent) at a greater than therapeutic level of 0.2 mg/L
- diazepam (benzodiazepine with anxiolytic, sedative, muscle relaxant and anti-convulsant effects) at a therapeutic level of 0.4 mg/L
- THC (illicit drug) at 2 ug/L
Mr Griffiths reports:
"Methadone is an analgesic and central nervous system depressant with similar pharmacological properties to morphine. It has effects typical of opioids – analgesia, sedation, respiratory depression, hypothermia, euphoria, miosis (pin point pupils), decreased gastrointestinal motility, nausea and vomiting and urinary retention………..In combination with other CNS depressants (eg oxycodone, mirtazapine, olanzapine, diazepam and THC) the respiratory depressant effects of methadone will be enhanced. It has been recognised that many cases of methodone-induced death are not attributable to methadone alone, but to the combined effects of methadone and another drug or drugs.
…..The effects of opioids like oxycodone reflect their depressant effects on the CNS and include analgesia, respiratory depression, drowsiness and sedation and cognitive changes……Therapeutic and toxic levels overlap. It is reported that individuals may tolerate therapeutic levels up to 0.3 mg/L while toxic levels may be as low as 0.2 mg/L in an individual without tolerance, particularly when in the present of other CNS depressants.
….Fluoxetine should not be taken in combination with other drugs which also act to increase serotonin brain levels.
….Mirtazapine is indicated in the treatment of depression…..It’s antidepressant activity is believed to be related to the enhanced release of noradrenaline and serotonin at nerve junctions. Mirtazapine also has histaminergic properties and is, therefore relatively sedating.
…Olanzapine…symptoms of overdose include sedation, respiratory depression, cardiac arrhythmias, agitation, extrapyramidal effects, aspiration and hypotension or hypertension.
…Diazepam…in combination with other central nervous system depressants (eg oxycodone, mirtazapine, olanzapine, diazepam and THC) the sedative effects of diazepam will be enhanced.
…THC has its greatest effect on the central nervous and cardiovascular systems ".
Dr Christopher Lawrence, State Forensic Pathologist, Statewide Forensic Medical Services carried out the autopsy of Mr Davis and reports:
"Toxicology reveals levels of fluoxetine and olanzapine above therapeutic levels as well as mirtazapine, methadone, oxycodone & diazepam. I understand that he had just been started on methadone 3 days before and deaths due to respiratory depression in this early period are common because of the absence of tolerance. There are interactions between fluoxetine and oxycodone, methadone & mirtazapine which increase its toxicity and an interaction between olanzapine and methadone due to effects on cardiac conduction (Long QT interval)."
I am satisfied that a full and detailed investigation has been undertaken in relation to the death of Mr Davis and that there are no suspicious circumstances.
Section 5.6 of The Tasmanian Methadone Policy 2000 published by the Department of Health and Human Services states that:
"The concurrent use of alcohol and other drugs with methadone by patients may threaten their safety and result in management difficulties. These drugs may be illegal substances such as heroin and amphetamines or legal substances such as alcohol or prescribed medications…..Patients should be warned of the high risks associated with mixing depressant drugs"
It further states that:
"Recent Australian research has demonstrated that deaths involving methadone are often the result of concurrent use of several drugs, often with synergistic depressant actions. In addition to methadone, drugs like alcohol and benzodiazepines are often present in large amount. Attempts should be made during the treatment of patients to assess and monitor their use of other drugs. This may involve observation at the time of dosing, consultation with the patient, urine testing and self reporting.
Appendix V of the Policy states that Methadone interacts with benzodiazepines and codeine, two drugs Mr Davis was taking, along with many other drugs. It does not appear from the list of drugs in Appendix V that any other drugs Mr Davis was taking would have adversely reacted with Methadone.
The report of Mr Griffiths from Forensic Science Tasmania states that when methadone is taken with other central nervous system depressants such as oxycodone, mirtazapine, olanzapine, diazepam and TCH the "respiratory depressant effects of methadone will be enhanced."
Mr Davis clearly posed a significant challenge in respect of treatment for his addiction in that he was already taking medications to treat his bipolar disorder, depression and neck pain. It is apparent that Dr Jackett, Mr Davis’ General Practitioner for many years was unaware until 30 July 2009 that Mr Davis was using Oxycodone illegally and it is also possible that he concealed his apparently consistent use of cannabis.
Dr Jackett sought appropriate assistance and advice when he became aware of Mr Davis’ illicit oxycodone use and suggested in-patient detoxification.
Steps taken by Dr Bourke upon referral of Mr Davis appear appropriate in that a thorough history was taken and a management plan including future review were put in place. It is unclear whether Dr Bourke provided written information to Mr Davis as contained in Section 3 of the Tasmanian Methadone Policy 2000 including but not limited to an overview of policies and procedures of the program, the nature of methodone (addictive qualities, side effects and drug interactions), hazards and problems associated with the use of methadone.
The MIMS (2004) lists contradictions for methadone however Mr Davis did not fall within any of these categories. Taking other medications which affect the central nervous system in a sedative manner would have been a risk for Mr Davis however I accept that in Dr Jackett’s clinical opinion methadone was appropriate having regard to the fact that Mr Davis had refused in-patient detoxification and given that he had sought further advice.
Mr Davis died as a result of combined drug (fluoxetine, olanzapine, mirtazapine, methadone, oxycodone and diazepam) intoxication.
This is another unfortunate case where a person has combined the use of prescribed drugs with illicit drugs and the combination has proved fatal.
Although the outcome in this case may not have been affected it is of concern that the new Tasmanian Opioid Pharmacotherapy Policy and Clinical Practice Standards first proposed some years ago has apparently not been implemented. This policy was to replace the present Tasmanian Methadone Policy 2000 and address many of the shortfalls of that earlier Policy. It is surely in the interests of public health that any improved revised model be implemented as soon as possible.
The continued ready illicit access to prescribed Schedule 8 medications such as Oxycontin has been highlighted in a number of coronial findings over the last 5 years. I encourage those involved in the roll-out of the real time reporting capability of the supply of prescribed Schedule 8 drugs and the improvement of clinical decision making by medical practitioners in relation to opioid prescribing to bring those projects to the desired conclusion as soon as possible.
I wish to conclude by conveying my sincere condolences to the family of Mr Davis
DATED: 25 January 2011 at Hobart in the State of Tasmania.