What happened

Seeking to eliminate sodium chloride from his diet based on perceived health risks, the 60-year-old man asked ChatGPT for alternatives and was advised to use sodium bromide, a chemical not intended for human consumption. 

The substitution resulted in severe psychiatric symptoms including paranoia, hallucinations and insomnia, neurological issues, muscle co-ordination issues (ataxia), and a three-week hospital stay before the correct diagnosis and treatment were provided. 

Laboratory analysis revealed over 200 times the normal limit of bromide in the man's blood. Sodium bromide is a toxic substance once used medicinally, but its dangers have been well established for decades. 

Why it happened

The outcome stemmed from the chatbot’s reliance on internet-sourced information, its lack of built-in clinical judgment, and the known tendency for AI chatbots to “hallucinate” or offer decontextualised, inaccurate medical recommendations without properly disclosing the relevant risks.

Furthermore, the chatbot failed to provide any health warning regarding its suggested substitute; medical experts said that such advice would never be offered by a licensed professional.