Prolonged persistent anterograde amnesia due to chronic self-prescribed midazolam therapy for insomnia

Anterograde amnesia and other memory impairments are well-documented adverse effects associated with benzodiazepine use, particularly in cases of prolonged or unsupervised intake. This case report describes the residual cognitive complications resulting from chronic self-administration of midazolam in a 30-year-old male with no previous psychiatric history. The patient reported an oral intake of midazolam 7.5 mg, three times per week at bedtime, over a 6-month period for the self-treatment of insomnia. Although initially effective, this regimen gradually led to significant memory impairment. Despite drug discontinuation, cognitive complaints persisted, and insomnia relapsed. Neuropsychological assessment revealed substantial deficits in short-term and anterograde memory, consistent with benzodiazepine-related cognitive dysfunction. Brain imaging and electroencephalography were unremarkable, and depressive symptoms were ruled out as contributing factors. Polysomnography (PSG) confirmed the presence of chronic insomnia with reduced sleep efficiency. Trazodone 100 mg once daily was prescribed and the patient was referred for cognitive behavioral therapy for insomnia (CBT-I), however, he declined the psychotherapeutic approach and opted for pharmacological management only. After 4 weeks, subjective sleep quality improved markedly, but cognitive performance showed only minimal improvement. This case highlights the potential neurocognitive risks associated with prolonged and unsupervised benzodiazepine use, particularly its detrimental impact on memory consolidation. It highlights the urgent need to enhance patient education and proactively identify self-medication behaviors. Ensuring therapeutic oversight and promoting evidence-based insomnia treatments are essential to preventing long-term cognitive sequelae and improving safety in clinical neuropsychiatric care.