Optimising alkalinisation and its effect on QRS narrowing in tricyclic antidepressant poisoning.

AIMS: The objectives were to determine the effect of NaHCO3 and/or mechanical ventilation on the biochemical profile and serum alkalinisation in tricyclic antidepressant (TCA) poisoning and investigate the impact of effective alkalinisation therapy on the QRS interval in TCA poisoning. METHODS: This was a retrospective review of TCA poisonings from three Australian toxicology units and a poisons information centre (Jan 2013 to Jan 2019). We included patients with TCA toxicity who ingested>10 mg/kg or had clinically significant toxicities consistent with TCA poisoning, and analysed patients' clinical, electrocardiogram and biochemical data. RESULTS: Of 210 patients, 84 received NaHCO3 and ventilation (dual therapy), 12 NaHCO3 , 46 ventilation and 68 supportive care treatment. When compared with single/supportive groups, patients who received dual therapy had taken a significantly higher median dose of TCA (1.5 g vs1.3 g, P < .001), a longer median maximum QRS interval (124 ms, interquartile ranges [IQR] 108-138 vs106 ms, IQR 98-115, P < .001) and were more likely to have seizures (14% vs3%, P = .006) and arrhythmias (17% vs1%, P < .001). The dual therapy group demonstrated greater increases in serum pH (median 0.11, IQR 0.04-0.17) compared to the single/supportive therapy group (median 0.03, IQR -0.01-0.09, p < .001). A greater proportion of patients reached the target pH 7.45-7.55 in the dual therapy group (59%) compared to the single/supportive therapy group (10%) (P < .001). For each 100 mmol bolus of NaHCO3 given, the median increase in serum sodium was 2.5 mmol/L (IQR 1.5-4.0). QRS narrowing occurred twice as quickly in the dual therapy vs single/supportive therapy group. CONCLUSIONS: A combination of NaHCO3 and mechanical ventilation was most effective in achieving serum alkalinisation and was associated with a more rapid narrowing of the QRS interval. We advise that the maximal dose of NaHCO3 should be <400 mmol (6 mmol/kg).

Changes in sales of analgesics to pharmacies after codeine was rescheduled as a prescription only medicine.

OBJECTIVE: To investigate changes in sales to pharmacies of over-the-counter (OTC) and prescription analgesics, cold and flu products, and cough suppressants after the rescheduling of codeine as a prescription only medicine in February 2018. DESIGN: Interrupted time series analysis of sales to pharmacies. SETTING: Pharmaceutical sales to community pharmacies in Australia, March 2015 - March 2019. The period January 2017 (month after rescheduling was announced) to January 2018 (month before rescheduling was implemented) was excluded from the time series analysis. MAIN OUTCOME MEASURES: Monthly pack and tablet sales per 10 000 population of OTC and prescription analgesics, cold and flu products, and cough suppressants. RESULTS: During 2016, 7586 packs and 248 127 tablets of OTC codeine per 10 000 population were sold to pharmacies; in the 14 months after rescheduling, a small level increase in monthly prescription codeine sales was evident (2247 tablets/capsules per 10 000 population; 95% CI, 1231-3264 per 10 000 population). Monthly OTC analgesic sales increased by 258 (95% CI, 151-365) packs per 10 000 population and 37 856 (95% CI, 26 143-49 569) tablet/capsules per 10 000 population. Monthly sales of single ingredient paracetamol (41 415 [95% CI, 31 374-51 456] tablets/capsules per 10 000 population), ibuprofen (1392 [95% CI 916-1868] tablets/capsules per 10 000 population), paracetamol/ibuprofen (1618 tablets [95% CI, 1567-1669] tablets/capsules per 10 000 population), and other paracetamol combinations (233 [95% CI, 112-353] tablets/capsules per 10 000 population) all increased, but not those of prescription analgesic products not containing codeine. Rises for OTC cold/flu products containing the opioid derivative dextromethorphan were small; sales of OTC cough suppressants containing opioid derivatives (dextromethorphan, pholcodine, dihydrocodeine) did not change. CONCLUSIONS: The rescheduling of codeine was followed by increased sales to pharmacies of paracetamol, ibuprofen, and paracetamol combination products. While these products carry no risk of dependence, their inappropriate use is also associated with harms that warrant adverse event monitoring.

Paracetamol poisoning-related hospital admissions and deaths in Australia, 2004-2017.

OBJECTIVES: To assess the numbers of paracetamol overdose-related hospital admissions and deaths in Australia since 2007-08, and the overdose size of intentional paracetamol overdoses since 2004. DESIGN, SETTING: Retrospective analysis of data on paracetamol-related exposures, hospital admissions, and deaths from the Australian Institute of Health and Welfare National Hospital Morbidity Database (NHMD; 2007-08 to 2016-17), the New South Wales Poisons Information Centre (NSWPIC; 2004-2017), and the National Coronial Information System (NCIS; 2007-08 to 2016-17). PARTICIPANTS: People who took overdoses of paracetamol in single ingredient preparations. MAIN OUTCOME MEASURES: Annual numbers of reported paracetamol-related poisonings, hospital admissions, and deaths; number of tablets taken in overdoses. RESULTS: The NHMD included 95 668 admissions with paracetamol poisoning diagnoses (2007-08 to 2016-17); the annual number of cases increased by 44.3% during the study period (3.8% per year; 95% CI, 3.2-4.6%). Toxic liver disease was documented for 1816 of these patients; the annual number increased by 108% during the study period (7.7% per year; 95% CI, 6.0-9.5%). The NSWPIC database included 22 997 reports of intentional overdose with paracetamol (2004-2017); the annual number increased by 77.0% during the study period (3.3% per year; 95% CI, 2.5-4.2%). The median number of tablets taken increased from 15 (IQR, 10-24) in 2004 to 20 (IQR, 10-35) in 2017. Modified release paracetamol ingestion report numbers increased 38% between 2004 and 2017 (95% CI, 30-47%). 126 in-hospital deaths were recorded in the NHMD, and 205 deaths (in-hospital and out of hospital) in the NCIS, with no temporal trends. CONCLUSIONS: The frequency of paracetamol overdose-related hospital admissions has increased in Australia since 2004, and the rise is associated with greater numbers of liver injury diagnoses. Overdose size and the proportion of overdoses involving modified release paracetamol have each also increased.

Carols by glow sticks: a retrospective analysis of Poisons Information Centre data.

OBJECTIVE: To win a Christmas hamper. We also devised a study of our most festive seasonal poisoning, to demonstrate how hard we are working while everyone else is partying. DESIGN: Retrospective analysis of the New South Wales Poisons Information Centre database, which we searched for exposures to the substance code "Cyalume light sticks/glow toys" from 1 July 2013 to 30 June 2017. SETTING: A dimly lit basement with a constantly ringing phone. At the other end of the phone was a highly anxious parent and a luminescent child. MAIN OUTCOME MEASURES: Number of glow stick exposures, route of exposures, patient demographics and seasonal trends in exposures. RESULTS: There were 2918 glow stick exposures over the 4-year study period. The vast majority of exposures (94%) were in children aged 14 years and younger. Medical complications were very rare. Glow stick exposures were 4.38 times more likely in December (95% CI, 3.02-6.35; P < 0.001). Statistically significant increases were also observed in October, November, January, February and March. Glow stick exposures were 4.20 times more likely during the holiday period of 1 December to 7 January (95% CI, 3.42-5.15; P < 0.001), 2.52 times more likely over summer (95% CI, 2.12-3.00; P < 0.001), and 1.77 times more likely during school holidays (95% CI, 1.47-2.13; P < 0.001). CONCLUSIONS: This epidemic of poisoning is perhaps due to mass seasonal synaesthesia. The lack of any significant adverse consequences highlights the contribution that 50 years of injury prevention has made to everyone having a Merry Christmas and a Happy New Year.

Patterns of poisoning exposure at different ages: the 2015 annual report of the Australian Poisons Information Centres.

OBJECTIVES: To characterise the types of calls received by Australian Poisons Information Centres (PICs) in Australia, and to analyse poisoning exposures by age group, circumstances of exposure, and the types of substances involved. Design, setting: Retrospective analysis of call records from all four Australian PICs (national coverage). MAIN OUTCOME MEASURES: Basic demographic information; exposure circumstances, substance types involved in each age group; recommendations for management (eg, stay at home, go to hospital). RESULTS: There were 204 906 calls to Australian PICs in 2015, 69.0% from the general public, 27.9% from health professionals; 16.2% of calls originated from hospitals. 170 469 calls (including re-calls about an exposure) related to 164 363 poison exposure events; 64.4% were unintentional, 18.1% were the consequences of medication error, and 10.7% involved deliberate self-poisoning. Most exposures were of 20-74-year-old adults (40.1%) or 1-4-year-old toddlers (36.0%). The PICs advised callers to stay at home for 67.4% of exposures, and to present to hospital for 10.9%. The most common substances involved in exposures overall were household cleaners (10.2%) and paracetamol-containing analgesics (7.3%). Exposures of infants and toddlers were most frequently to household cleaning substances (17.8%, 15.3% respectively) and personal care items (6.6%, 7.3%); callers were usually advised to stay at home (88.5%, 86.4%). Deliberate self-poisoning (49.1%) and hospital referral (23.9%) were most frequent for adolescents. Exposures of adults (20-74 years) frequently involved psychotropic pharmaceuticals (17.8%) or painkillers (15.1%). Exposures in adults over 74 were typically medication errors involving cardiovascular (23.6%), anticoagulant (4.6%), or antidiabetic (4.1%) medications. CONCLUSIONS: Poisoning is a significant public health problem throughout life, but the nature of the hazards differs markedly between age groups. PIC data could inform strategic public health interventions that target age-specific poisoning hazards.

A decade of Australian methotrexate dosing errors.

OBJECTIVE: Accidental daily dosing of methotrexate can result in life-threatening toxicity. We investigated methotrexate dosing errors reported to the National Coronial Information System (NCIS), the Therapeutic Goods Administration Database of Adverse Event Notifications (TGA DAEN) and Australian Poisons Information Centres (PICs). DESIGN AND SETTING: A retrospective review of coronial cases in the NCIS (2000-2014), and of reports to the TGA DAEN (2004-2014) and Australian PICs (2004-2015). Cases were included if dosing errors were accidental, with evidence of daily dosing on at least 3 consecutive days. MAIN OUTCOME MEASURES: Events per year, dose, consecutive days of methotrexate administration, reasons for the error, clinical features. RESULTS: Twenty-two deaths linked with methotrexate were identified in the NCIS, including seven cases in which erroneous daily dosing was documented. Methotrexate medication error was listed in ten cases in the DAEN, including two deaths. Australian PIC databases contained 92 cases, with a worrying increase seen during 2014-2015. Reasons for the errors included patient misunderstanding and incorrect packaging of dosette packs by pharmacists. The recorded clinical effects of daily dosage were consistent with those previously reported for methotrexate toxicity. CONCLUSION: Dosing errors with methotrexate can be lethal and continue to occur despite a number of safety initiatives in the past decade. Further strategies to reduce these preventable harms need to be implemented and evaluated. Recent suggestions include further changes in packet size, mandatory weekly dosing labelling on packaging, improving education, and including alerts in prescribing and dispensing software.

Clenbuterol toxicity: a NSW poisons information centre experience.

OBJECTIVE: To describe the epidemiology and toxicity of clenbuterol in exposures reported to the NSW Poisons Information Centre (NSWPIC). DESIGN AND SETTING: Retrospective observational study analysing data from all calls about clenbuterol exposure recorded in the NSWPIC database from 1 January 2004 to 31 December 2012. The NSWPIC coversthe Australian jurisdictions New South Wales, Tasmania and the Australian Capital Territory 24 hours a day and provides after-hours cover for the rest of Australia for 7 nights each fortnight. MAIN OUTCOME MEASURES: Total number of exposures, source of call (hospital, health care worker, member of the public), time from exposure to call, reasons for drug use, clinical features and advice given. RESULTS: Callers reported 63 exposures to clenbuterol, with a dramatic increase from three in 2008 to 27 in 2012. Of the 63 calls, 35 were from hospital, two from paramedics, one from general practice and 21 direct from the public. At least 53 patients (84%) required hospitalisation. The commonest reasons for use were bodybuilding and slimming. The most common features were tachycardia (24 patients), gastrointestinal disturbance (16) and tremor (11). Exposure was also associated with cardiotoxicity including one cardiac arrest in a 21-year-old man. CONCLUSION: Although a well recognised doping issue among elite athletes, clenbuterol use has spread out into the general public, especially during 2012, and should be considered in patients using bodybuilding or slimming products who present with protracted sympathomimetic features. The potential for misuse of this substance requires reconsideration of its current poison schedule registration and its availability.

Toxicokinetics of thebaine in those consuming non-food grade poppy seeds as a tea.

INTRODUCTION: Thebaine is an alkaloid in poppy seeds that is neurotoxic to animals. Data on its clinical effects and toxicokinetics in people are minimal. In 2022, poppy seeds high in thebaine entered the Australian food market, and people consuming tea made from these poppy seeds developed poisoning. METHODS: Three patients who drank poppy seed tea and developed neuromuscular toxicity consented for thebaine to be quantitated in serial blood samples. Blood samples were analyzed by liquid chromatography with high-resolution mass spectrometry. RESULTS: Case 1: A man in his 60s presented with drowsiness, vomiting, malaise and myoclonus. He developed metabolic acidosis with hyperlactataemia, acute kidney injury requiring haemodialysis, convulsions, rhabdomyolysis, and was in the hospital for 18 days. The admission thebaine blood concentration was 2.1 mg/L, and the apparent elimination half-life was 14.8 h. Case 2: A man in his 30s presented with myoclonus, rigidity, vomiting, and dizziness. He developed metabolic acidosis with hyperlactataemia, acute kidney injury, and myalgias. The admission thebaine blood concentration was 4.1 mg/L, and the apparent elimination half-life was 11.6 h. Case 3: A man in his 30s presented with myoclonus, rigidity, clonus, diaphoresis, and abdominal pain. The admission thebaine blood concentration was 2.2 mg/L, and the apparent elimination half-life was 8.3 h. DISCUSSION: Neuromuscular toxicity, metabolic acidosis with hyperlactataemia, acute kidney injury, and gastrointestinal symptoms were prominent clinical features in these patients after drinking poppy seed tea. Effects persisted for days, and all survived, despite thebaine concentrations far exceeding those in published forensic reports, although human data are sparse. Compared to rats, the thebaine apparent elimination half-life is much longer in humans who develop symptoms at lower concentrations. CONCLUSIONS: Despite relatively high thebaine blood concentrations and moderate to severe poisoning, outcomes were favourable with early presentations. It is possible that acute kidney injury prolongs the apparent elimination half-life of thebaine.

A cluster of acute thebaine poisonings from non-food grade poppy seeds in the Australian food supply.

INTRODUCTION: Poppy seed tea is used for its opioid effects and contains multiple opium alkaloids, including morphine, codeine, papaverine, and thebaine. Animal studies indicate thebaine has strychnine-like properties, but there is limited literature describing human thebaine poisoning. We describe a cluster of acute thebaine poisoning in people ingesting tea made using poppy seeds with high thebaine content that entered the Australian food supply chain. METHODS: This is an observational study of patients poisoned after drinking poppy seed tea. Cases were identified by three prospective toxicovigilance systems: the Emerging Drug Network of Australia collaboration, the New South Wales Prescription, Recreational and Illicit Substance Evaluation program, and the Emerging Drugs Network of Australia Victoria study. We report characteristics of clinical toxicity in cases with reported ingestion of poppy seed tea and analytical confirmation of thebaine exposure. RESULTS: Forty cases presenting with multi-system toxicity following poppy seed tea ingestion were identified across seven Australian states/territories from November 2022 to January 2023. Blood testing in 23 cases confirmed high thebaine concentrations. All 23 were male (median age 35, range 16-71 years). All patients experienced muscle spasms. Rigidity was described in nine, convulsions in six, while rhabdomyolysis, acute kidney injury, and metabolic acidosis occurred in five patients. There were two cardiac arrests. The thebaine median admission blood concentration was 1.6 mg/L, with a range of 0.1-5.6 mg/L, and was the dominant opium alkaloid in all samples. Convulsions, acute kidney injury, metabolic acidosis, and cardiac arrest were associated with increasing median thebaine concentrations. Four patients were managed in the Intensive Care Unit, with two receiving continuous kidney replacement therapy (one also received intermittent haemodialysis) for kidney injury. There was one death. CONCLUSIONS: Thebaine toxicity, like strychnine poisoning, resulted in neuromuscular excitation characterized by muscle spasm, rigidity, and convulsions. Severe toxicity, including acute kidney injury, metabolic acidosis, and cardiac arrest, appears dose-dependent.

Energy drinks: health risks and toxicity.

OBJECTIVES: To describe the epidemiology and toxicity of caffeinated energy drink exposures in Australia. DESIGN, SETTING AND SUBJECTS: Retrospective observational study analysing data from calls regarding energy drink exposures recorded in the database of an Australian poisons information centre over 7 years to 2010. MAIN OUTCOME MEASURES: Type of exposure; co-ingestants; symptoms reported; and reported hospitalisations. RESULTS: Callers reported 297 exposures to energy drinks, which showed an increasing annual trend from 12 in 2004 to 65 in 2010. Median age for the 217 subjects with recreational exposure was 17 years (interquartile ratio [IQR], 15-21; range, 11-60) and 57% were male. One hundred recreational users co-ingested other substances, predominantly alcohol (50) or other caffeinated products (44). The number of energy drinks consumed in one session varied greatly (median, 5 units; IQR, 3-8; range, 1-80). Most subjects who reported recreational use reported experiencing symptoms (87%). The most common symptoms were palpitations, agitation, tremor and gastrointestinal upset. Twenty-one subjects had signs of serious cardiac or neurological toxicity, including hallucinations, seizures, arrhythmias or cardiac ischaemia. At least 128 subjects (57 with no co-ingestants) required hospitalisation. CONCLUSIONS: Reports of caffeine toxicity from energy drink consumption are increasing, particularly among adolescents, warranting review and regulation of the labelling and sale of these drinks. Educating adolescents and increasing the community's awareness of the hazards from energy drinks is of paramount importance.

A cluster of lysergic acid diethylamide (LSD) poisonings following insufflation of a white powder sold as cocaine.

OBJECTIVE: Adulteration, substitution or contamination of illicit substances can have clinically significant implications when other illicit substances are included. Such circumstances can present as clusters of poisonings, including severe toxicity and death following exposure to unexpected illicit substances. We report a cluster of laboratory-confirmed lysergic acid diethylamide (LSD) in a powder that was sold as cocaine and used recreationally. METHODS: The Prescription, Recreational and Illicit Substance Evaluation (PRISE) program established by the New South Wales Ministry of Health includes State-based hospital toxicology services, Poisons Information Centre, Forensic & Analytical Science Service and emergency services to identify clusters of severe and unusual toxicity associated with substance use. PRISE criteria include a known cluster (geographically or situationally related) of people with acute severe toxicity, especially when accompanied by a toxidrome that is inconsistent with the history of exposure. A timely comprehensive drug screen and quantification is performed in eligible cases and the results are related to the clinical features. The need for a public health response is then considered. Four individuals inhaled a white powder that was sold as cocaine and developed severe toxicity that was not consistent with cocaine which prompted transfer to hospital for further management. RESULTS: LSD was confirmed in four subjects, and the concentrations in 3 of the individuals were 0.04-0.06 mg/L which are among the highest reported in the literature. Common clinical features were hallucinations, agitation, vomiting, sedation, hypertension, and mydriasis. One subject required intubation and admission to the intensive care unit, two required overnight admission, and the fourth was discharged following oral diazepam after observation. No subject suffered persistent injury. CONCLUSIONS: A close working relationship between pre-hospital emergency services, hospital-based clinical services, public health authorities, and analytical laboratories appears to be advantageous. Favourable clinical outcomes are observed from LSD poisoning despite high exposures with good supportive care.

Angiotensin axis antagonists increase the incidence of haemodynamic instability in dihydropyridine calcium channel blocker poisoning.

CONTEXT: Amlodipine, a dihydropyridine calcium channel blocker (CCB), is the leading cause of cardiovascular drug-related overdose deaths in the USA. In contrast, angiotensin-II receptor blockers (ARBs) and angiotensin converting enzyme inhibitors (ACEIs) cause minimal toxicity in overdose. ACEIs/ARBs are often combined with dihydropyridines in hypertension treatment. Co-ingested ARBs/ACEIs may significantly contribute to the toxicity of dihydropyridine, but this has not been investigated. OBJECTIVE: To investigate the clinical outcomes from dihydropyridine overdoses with ARBs/ACEIs versus dihydropyridine overdoses alone. METHODS: This was a retrospective study of patients reported to the New South Wales Poisons Information Centre (NSW PIC) and 3 toxicology units (Jan 2016 to Jun 2019) in Australia. Patients >14 years who took an overdose of dihydropyridines (amlodipine, felodipine, lercanidipine, nifedipine) were included. Concurrent overdoses with non-dihydropyridine CCBs, alpha-blockers and beta-blockers were excluded. Patient demographics, drugs exposure details, serial vital signs, treatments and outcome were collected. RESULTS: There were 100 patients. 68 took mixed overdoses of dihydropyridines with ARBs/ACEIs and 32 took single overdoses of dihydropyridines without ARBs/ACEIs. The mixed group had lower median nadir mean arterial pressures (62 vs 75 mmHg, p < 0.001), more frequently had hypotension (OR 4.5, 95%CI: 1.7-11.9) or bradycardia (OR 8.8, 95%CI: 1.1-70). Multivariable analysis indicated the mixed overdoses had an 11.5 mmHg (95%CI: 4.9-18.1) lower minimum systolic blood pressure (SBP) compared with the single group; other factors associated with a lower minimum SBP were higher doses [2.3 mmHg (95%CI: 1.1-3.5) lower per 10 defined daily doses] and younger age [2.2 mmHg (95%CI: 0.3-4.2) higher per decade]. A larger proportion of the mixed ingestion group received intravenous fluids (OR 5.7, 95%CI: 1.8-18.6) and antidotes and/or vasopressors (OR 2.9, 95%CI: 1.004-8.6). CONCLUSION: Combined overdoses of dihydropyridines with ARBs/ACEIs caused more significant hypotension and required more haemodynamic support than overdoses of dihydropyridines alone.