Background
Tramadol is a synthetic opioid analgesic that acts mainly on the µ-opioid receptors with less activity on norepinephrine and serotonin by reuptake inhibition. In the last decade, tramadol addiction presents an increasing medical and legal crisis in Egypt.

Objective
Few works in the literature studied the cognitive profile in tramadol-dependent patients without focusing on prolonged duration of dependence or on its use in high doses.

Patients and methods
The present work studied the cognitive functions in 30 tramadol-dependent patients in comparison to 30 healthy cross-matching controls regarding short-term and long-term memory, visuospatial function, executive functions, and reaction time. The cognitive battery used in this study included mini-mental state examination, montreal cognitive assessment scale, brief visuospatial memory test-revised, and P300-evoked potential measuring.

Results
The results have shown that tramadol-dependent patients have affection in memory, visuospatial, and executive functions and in reaction time compared with healthy individuals as evidenced by mini-mental state examination (P=0.003), montreal cognitive assessment scale (P<0.001), brief visuospatial memory test-revised (P=0.016), and P300 latency (P<0.001).