Investigation into Spike of Adverse Events for Vyvanse in Australia

In recent months, Australia's Therapeutic Goods Administration (TGA) has launched an investigation into a significant increase in adverse event reports associated with Vyvanse, the country's most commonly prescribed medication for Attention Deficit Hyperactivity Disorder (ADHD). This inquiry comes on the heels of a surge in prescriptions, which rose from approximately 958,831 in 2022 to over 1.78 million in 2024, as reported by the Pharmaceutical Benefits Scheme (PBS). The rise in adverse reports, which shot up from just nine in the previous six months to 320 in the first half of this year, has raised alarms among health officials and medical practitioners alike.

The TGA's investigation aims to assess concerns regarding the safety and effectiveness of Vyvanse, known scientifically as lisdexamfetamine dimesilate. Among the most frequently reported adverse events are ineffectiveness, anxiety, product labeling issues, therapeutic response decreases, and insomnia. An analysis by the TGA indicates that while an increase in medication usage typically correlates with a rise in adverse event reports, the number of reports regarding Vyvanse has reached a threshold significant enough to warrant a safety signal. This signal suggests a potential causal relationship between the medication and the reported adverse effects, a concern echoed by experts in the field.

Dr. Karuppiah Jagadheesan, a spokesperson for the Royal Australian and New Zealand College of Psychiatrists (RANZCP), noted that the spike in social media discussions around Vyvanse likely contributed to the higher reporting rate. "Social media is very powerful, and particularly negative experiences can be shared rapidly, amplifying concerns among users," Dr. Jagadheesan explained. He emphasized that while adverse events are reported by a minority of users, those currently on the medication should not panic if it remains effective for them. He advised patients experiencing side effects or ineffectiveness to consult their healthcare providers.

The TGA has been in communication with Takeda Pharmaceuticals Australia Pty Ltd, the manufacturer of Vyvanse. Takeda maintains that there have been no changes to the formulation of Vyvanse, and strict quality controls are in place, despite earlier issues with labeling that included typographical errors. A spokesperson from the company stated that this move to enhance production capacity was necessary due to increased demand for the medication. However, the company also acknowledged that these labeling errors might have contributed to the rise in adverse event reports.

Dr. Sarahn Lovett, vice president of the Australasian ADHD Professionals Association (AADPA), corroborated that side effects reported for Vyvanse align with those common to stimulant medications. She stressed that users should continue their treatment if the medication is effective, as stopping it abruptly is not recommended for those managing ADHD symptoms effectively.

Dr. Tim Jones, spokesperson for the Royal Australian College of General Practitioners (RACGP) on ADHD, cautioned that the rise in prescriptions does pose a risk for adverse effects, particularly in patients with complex mental health histories. He indicated that there is an urgent need for balanced discussions surrounding the benefits and risks of stimulant medications, especially for those patients who may experience heightened side effects such as anxiety and insomnia.

As the TGA continues its investigation, it remains to be seen what regulatory actions, if any, will be implemented in response to these findings. The TGA has stated that any significant outcomes will be communicated to the public and healthcare professionals. Meanwhile, the ADHD Foundation has not reported an uptick in complaints related to Vyvanse, suggesting that while the reports of adverse events have increased, they have not necessarily translated into widespread public concern. As the situation develops, patients and healthcare providers alike are urged to stay informed and engaged in dialogue about the implications of these findings for ADHD treatment in Australia.