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A service commissioned by the HPA. The role of medicines regulation in prevention of serious poisoning. Nick Bateman Professor in Clinical Toxicology & Consultant Physician RIE Director, NPIS Edinburgh. NPIS Edinburgh. CONTENT. Medicines Regulation Prescription and OTC products
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A service commissioned by the HPA The role of medicines regulation in prevention of serious poisoning Nick Bateman Professor in Clinical Toxicology & Consultant Physician RIE Director, NPIS Edinburgh NPIS Edinburgh
CONTENT • Medicines Regulation • Prescription and OTC products • 2. Prevention strategies • What works- and perhaps doesn’t • 3. Some ideas for the future
Medicines Regulation • European licensing structure • EMEA www.emea.europa.eu/ • 2. Member states actions • May take note of local circumstances • Prescription only • Pharmacy sale • General sale products (OTC)
REGULATORY ACTIONS • Changes to package/ presentation/ labelling (eg specific warnings) • Changes to category (eg drugs of potential abuse, prescription only, pharmacy supply, general sale) • Changes to indication (may limit supply, reduce hazard in “at risk” groups) via SPC, doctors letter etc • Licence revocation
WHAT THEY CANNOT DO Insist on entirely new formulations (eg antidote inclusion) if efficacy and safety in routine use demonstrated Withdraw products just because of problems in overdose if normal use acceptably safe
AVAILABILITY AND OVERDOSE • If it is not available you cannot take it: • EXAMPLES OF “INCIDENTAL” BENEFIT • Reye’s syndrome and aspirin (1963) • 1980s limitation on aspirin availability • Thioridazine withdrawal for arrhythmia risk autumn 2000
PROPORTION OF POISONING ADMISSIONS 1981-2000 ROYAL INFIRMARY EDINBURGH
PROPORTION OF ADMISSIONS PER ANNUM1981-2000 ROYAL INFIRMARY EDINBURGH
PRESCRIBING OF ANTIPSYCHOTIC DRUGS PER QUARTER, 2000-2001 EXPRESSED AS % OF TOTAL ANTIPSYCHOTICS - ENGLAND
TOXBASE accesses per quarter, 2000-2001 expressed as % of total antipsychotics - England Bateman et al 2003 BJCP 55: 596-03
AVAILABILITY AND OVERDOSE If it is is available can you make it safer? Child resistant containers Mode of supply Volume of purchase- generally for non prescription items (Opioid programmes)
CHILD RESISTANT CONTAINERS • Ingestion rate for all substances requiringCRCs declined from 5.7/1,000 children in 1973 to 3.4/1,000 children in 1978. • Reduction in exposures by 200,000 over 5 yr • 20 yr decline in deaths by poisoning 2.0/100,000 children to 0.5/100,000 National Injury Surveillance SystemandNational Center for Health Statistics(USA) Walton WW 1982 Pediatrics 69:363-70
Effectiveness of child-resistant packaging(Alabama)< 5 y-of-age 168 patients. Mean age 26 mo • 71% original container • 29% transferred to another container or found outside of its container • 33% involved a child-resistant closure Lembersky et al 1996 Vet Hum Tox 38:380-3
Effectiveness of child-resistant packaging(Alabama) • 20% of exposures opening properly closed child-resistant closure • 18.5% by opening a properly closed non-child-resistant closure. Child-resistance did not ensure child impenetrability Lembersky et al 1996 Vet Hum Tox 38:380-3
AVAILABILITY AND OVERDOSE • If it is is available can you make it safer? • Child resistant containers • Mode of supply • Volume of purchase
IRON OVERDOSE IN CHILDREN USA pre 1978 CRC for >500mg elemental iron After 1978 CRC for >250 mg elemental iron 1998 strip packs for >30 mg elemental iron
Unit-dose packaging of iron supplements >30mg Tenenbein, 2005 Arch Ped Adol Med 159: 557-60
AVAILABILITY AND OVERDOSE If it is is available can you make it safer? Child resistant containers Mode of supply Volume of purchase
Proportion of overdose deaths (95% CI) (censored) related to paracetamol Scotland 1995-2003 Ratio Post/Pre: 1.347 (1.076-1.639) p= 0.013 British Journal of Clinical Pharmacology 2006: 62: 573-581.
ADD THE ANTIDOTE? Methionine ?? (UK Paradote product) • Problems 1. How to prove efficacy in man 2. Mass medication 3. Increase in homocysteine in long term administration 4. Cost
ADD THE ANTIDOTE? • Acetylcysteine? <200mg/tablet (Andrus et al) “The efficacy should be tested” Andrus JP et al 2001 BMJ 323:634
AVAILABILITY AND OVERDOSE If it is is available can you make it safer? IF NOT : WITHDRAWAL?
WHAT REGULATORS CANNOT DO Withdraw products just because of danger in overdose without good reason
Scotland • Deaths in 3 categories Paracetamol (± ethanol) ONLY Paracetamol and other drugs Co-proxamol Paracetamol 325 mg Dextropropoxyphene 32.5 mg (opioid with Na+ channel blocking effects)
Estimated Fatal Toxicity Scotland per million prescription (95%CI)
Coproxamol efficacy Clinical data very weak- No evidence that better than paracetamol alone acutely and no chronic studies Sold to a Generic manufacturer in UK
WHAT UK REGULATOR DID Withdrew Coproxamol over a 2 year period
Analgesic prescribing, Items/quarter Scotland 2002-7 UK Legislation DEC 2004
Coproxamol deaths as % overdose deaths Scotland 2000-06 Legislation DEC 2004
Overdose opioid analgesic deaths : Scotland 2000-06 Legislation DEC 2004 Sandilands et al BJCP 2008 in press
AVAILABILITY AND OVERDOSE IDENTIFYING OTHER TARGETS ?? A new role for poisons centres
Studies on prescribing data and mortality in England + Wales 1980s and 90s FTI= deaths per million scripts
Prescription data, fatal poisonings and fatal toxicity index for individual antidepressants in Scotland, 2002-5 *** significantly different at 0.1% level (p<0.001)
ACTIONS • Changes to package/ presentation/ labelling (eg specific warnings) • Changes to category (eg drugs of potential abuse, prescription only, pharmacy supply, general sale ) • Changes to indication (? limit supply, reduce hazard in “at risk” groups) • Licence revocation