Pharmacovigilance and Adverse Drug Reaction Reporting in NZ (CARM)

Pharmacovigilance — Definition and Purpose

Pharmacovigilance is the science and activities relating to the detection, assessment, understanding, and prevention of adverse effects or any other drug-related problems. The goal is to ensure that the benefit-risk profile of medicines remains favourable throughout their post-marketing life. Pre-approval clinical trials involve thousands of patients over limited periods — rare adverse effects, effects in special populations (elderly, pregnant women, renally impaired), and long-term toxicities may not be detected until a medicine has been widely used in the community.

The NZ Centre for Adverse Reactions Monitoring (CARM)

The Centre for Adverse Reactions Monitoring (CARM) is located at the University of Otago (Dunedin) and is contracted by Medsafe to collect, analyse, and report adverse reactions to medicines, vaccines, herbal products, and dietary supplements in New Zealand. CARM receives spontaneous reports from health professionals and consumers, analyses signals, and feeds data to international pharmacovigilance networks including the WHO Uppsala Monitoring Centre (VigiBase — the world's largest ADR database).

Who Can Report to CARM?

Any health professional — medical practitioners, pharmacists, nurses, dentists, midwives — and consumers (patients, family members) can report to CARM. Pharmacists are strongly encouraged to report all suspected adverse reactions, particularly for: new medicines (black triangle designation in NZ); serious reactions (requiring hospitalisation, life-threatening, or fatal); reactions to herbal or complementary medicines; and unexpected reactions not described in the product datasheet.

What to Report

CARM asks reporters to submit: patient details (age, sex, weight if relevant, relevant medical history); the suspected medicine(s) (name, dose, route, start and stop dates); concomitant medicines; the adverse reaction description (onset, duration, outcome); and any de-challenge/re-challenge information (did the reaction resolve on stopping the drug? Did it recur on restarting?). Complete reports are more valuable — partial reports are still accepted.

The Reporting Process

Reports can be submitted online at the CARM website (carm.otago.ac.nz), by phone, or by post. Once received, CARM assigns a causality assessment using the WHO-UMC causality categories: Certain, Probable/Likely, Possible, Unlikely, Conditional/Unclassified, and Unassessable. The Naranjo Adverse Drug Reaction Probability Scale provides an alternative scoring system (score >9: definite; 5-8: probable; 1-4: possible; ≤0: doubtful).

Signal Detection and Action

CARM analyses aggregated data for signals — a pattern of ADR reports that may indicate a previously unrecognised adverse effect. When a signal is detected, CARM and Medsafe can take regulatory action: updating the product datasheet, issuing a prescriber/pharmacist letter (Dear Healthcare Provider letter), adding warnings, or in extreme cases suspending or withdrawing consent to market the medicine. High-profile examples in NZ include the withdrawal of rofecoxib (Vioxx) over cardiovascular risk and the addition of suicidality warnings to SSRIs.

Vaccine Adverse Event Reporting

Adverse events following immunisation (AEFI) are reported to CARM and also to the Immunisation Advisory Centre (IMAC). Pharmacists administering vaccines under a standing order or collaborative prescribing arrangement must be aware of AEFI reporting requirements, expected injection site reactions versus true systemic adverse reactions, and the management of anaphylaxis following immunisation (adrenaline 0.5 mg IM into the outer thigh, supine position, activate emergency services).