The alarming trend of off-label quetiapine use in New Zealand: an ongoing public health crisis

In 2010, United States (US) Attorney General Eric Holder warned of the dangers posed by pharmaceutical companies’ illegal acts, stating that such actions “can put public health at risk, corrupt medical decisions by health care providers, and take billions of dollars directly out of taxpayers’ pockets.” This statement coincided with AstraZeneca facing charges for off-label promotion of quetiapine (Seroquel) for unapproved conditions, including insomnia and anxiety.¹

AstraZeneca’s marketing practices resulted in a US$520 million fine, a mere fraction of quetiapine’s annual US sales of $6.8 billion in 2010.² The case exposed a troubling trend: between 2000 and 2007, publications suggesting off-label uses for quetiapine significantly outnumbered confirmatory trials, with AstraZeneca engaging doctors to conduct studies on unapproved uses.³

Despite legal repercussions and lack of solid evidence, off-label quetiapine prescriptions, particularly for insomnia, have surged globally.⁴ Studies in New Zealand revealed that nearly half of patients prescribed an antipsychotic received quetiapine,⁵ with up to 72% receiving it for off-label indications.⁶ This trend persists despite substantial risks associated with quetiapine use, even at low doses, including:

• Weight gain and metabolic disorders, including increased triglycerides⁷
• Higher risk of major adverse cardiovascular events, non-fatal ischemic stroke and cardiovascular death compared to Z-drugs⁸
• Potential for intentional abuse, with quetiapine being the most commonly misused antipsychotic in the US, accounting for 60.6% of all antipsychotic abuse cases.⁹

Despite warnings issued for over a decade, this growing health problem remains unmitigated. As of 2023, up to 1 in 41 adults in New Zealand were dispensed 25mg quetiapine, accounting for 63% of people dispensed an oral antipsychotic (excluding clozapine).¹⁰

In conclusion, the current pattern of quetiapine prescribing, particularly its widespread off-label use for insomnia, lacks evidence-based support and poses significant risks to patient health and healthcare sustainability. It underscores the ongoing challenges in ensuring that pharmaceutical use is driven by scientific evidence rather than marketing or convenience. The current off-label use of quetiapine in New Zealand is an ingrained practice of the prescribers based only on the ongoing exploitation of the deceptive marketing of its sedative side effect, which results from its H1 receptor binding profile (similar to that of promethazine or amitriptyline). In contrast, medications specifically developed, tested and approved for short-term insomnia management, such as zopiclone, are classified as controlled substances, while quetiapine prescribing remains relatively unrestricted.

Patients deserve treatments that have been thoroughly tested for both efficacy and safety in their specific conditions. Until robust evidence supports its use for insomnia, healthcare providers should exercise caution when considering low-dose quetiapine prescriptions for this purpose. The potential harm to individual patients and the broader public health implications of this prescribing trend demand immediate attention and action.