Inappropriate paracetamol ingestion is the leading cause for contacting Poisons Information Centres in Australia and New Zealand.15 Almost every home in Aotearoa (87 per cent in one study) has a supply of paracetamol (median 24g, two paracetamol-containing products).16 The problems that its oversupply and inappropriate use can bring provide useful talking points for the general concept of medicines safety in the home. Considering the safe use of paracetamol has the potential to resonate with patients because the drug is available so widely (on prescription and OTC, via pharmacies and supermarkets), in numerous formulations and products (often combination products), in different paediatric liquid strengths requiring weight-based dosing, and is used frequently by so many people.
Accidental harm from paracetamol toxicity is a concern, particularly with children and their risk of acute liver failure and (rarely) death. While the incidence of paediatric acute liver failure caused by paracetamol poisoning is low, it disproportionately affects Māori children – half of the cases in Aotearoa over a decade being tamariki Māori.17
The New Zealand National Poisons Centre receives an average of 804 calls per year relating to paracetamol ingestion in children.17 The most common reasons for paracetamol exposures vary by age group, with 53 per cent of children’s paracetamol exposures due to therapeutic errors and 44 per cent due to child exploratory behaviours. Intentional exposures were the most common reasons for paracetamol exposures in those aged 13–19 and 20–64 years, and 74 per cent of older adults’ exposures due to therapeutic errors.15
Health professionals can promote the safe and effective use of paracetamol in many ways, such as by prescribing for individual children rather than an entire family. Patient education, dosage and administration advice can be found on the Healthify website.18
A New Zealand Drug Foundation analysis of coronial data on fatal overdoses between 2017 and 2021 found at least one prescription or OTC medicine was listed on the toxicology report in 321 of 419 (77 per cent) closed cases.19 Sedatives (excluding opioids) were most heavily implicated, with prescription opioids second most implicated. Fifth in the list of legally available individual medicines implicated in overdose deaths was paracetamol. The list is, in order: diazepam (97 closed cases), zopiclone (72), codeine (64), morphine (64), paracetamol (59).
Appropriate paracetamol supply promotes waste reduction and safety in the home. It requires matching the quantity to the needs of the patient and condition, and ascertaining what supply is on hand already at home. For analgesia, paracetamol is often prescribed “as required”, for example:20
- Rx Paracetamol 500mg tablets: Sig 1–2 tablets q4h prn, up to qid (mitte 3 months).
Written in this way, the pharmacist will dispense 720 tablets: appropriate if the intention is for the patient to take paracetamol 1g on a regular basis, four times daily, for three months (eg, for osteoarthritis). But is this quantity appropriate for the patient in front of you? An alternative prescription might be:20
- Rx Paracetamol 500 mg tablets: Sig 1–2 tablets q4h prn, up to qid (mitte 180 tablets).
This quantity provides the patient with enough supply to take two tablets, twice daily, for a few days a week over a three-month period (eg, for intermittent headaches or pain), or two tablets, four times daily, for approximately three weeks (eg, for injury).20
The He Ako Hiringa EPiC (Evaluating Prescribing to inform Care) dashboard reveals high levels of dispensing of paracetamol (unsurprisingly). What is surprising is the ethnic breakdown, which shows Pacific peoples receive paracetamol at more than 1100 items per 1000 patients per annum, whereas Māori, Asian and European/Other peoples have a dispensing rate around or just below 700 items.21 There is no clear reason why this difference exists, but it may prompt additional considerations by prescribers and dispensers of paracetamol.