Methadone Withdrawal-Related Psychosis in a Patient With Hormone-Dependent Breast Cancer: A Case Report.

Methadone withdrawal usually presents as a classical opiate withdrawal syndrome, including symptoms such as restlessness, pupillary dilation, sweating, insomnia, irritability, sneezing, nausea, vomiting, and diarrhea. It rarely manifests as psychosis. Here, we discuss the case of a 43-year-old female with a history of long-term methadone use who presented with first-episode psychosis during methadone down-titration. She exhibited persecutory delusions and auditory hallucinations, unrelated to classical opiate withdrawal symptoms. Medical tests were unremarkable. The patient was diagnosed with first-episode psychosis and was involuntarily admitted to our psychiatric hospital. As she suffered from hormone-dependent breast cancer and presented paliperidone-induced hyperprolactinemia, we switched this drug to aripiprazole, a prolactin-sparing antipsychotic. Her psychotic symptoms remitted in six weeks, with no reintroduction of methadone. It remains unclear whether this presentation is attributable to a rare manifestation of withdrawal or methadone's antipsychotic properties, masking an underlying psychotic disorder. This case contributes to understanding psychosis emergence post-opioid withdrawal, underscoring the need for further investigation into withdrawal-related psychosis and opioid antipsychotic properties. It also prompts the discussion of antipsychotic treatment in patients with comorbid breast cancer, while evidence about hyperprolactinemia as a risk factor for breast cancer remains conflicting.