Increased risk of seizure in doses w/in & above the recommended range; in concomitant use w/ SSRIs, TCAs & other tricyclics (eg, cyclobenzaprine, promethazine), other opioids, MAOIs, neuroleptics & other drugs that reduce the seizure threshold; in naloxone administration for tramadol overdose. Patients w/ epilepsy, history of seizures or at risk of seizures eg, head trauma, metabolic disorders, alcohol & drug w/drawal, CNS infection; history of anaphylactic reactions w/ other codeines & opioids. Rare yet serious anaphylactic reactions. Consider alternative non-opioid therapy in patients w/ resp depression. Increased risk of resp depression in patients who are CYP2D6 ultra-rapid metabolizers. W/drawal symptoms may occur if therapy is abruptly stopped. Monitor for signs & symptoms of hyponatremia. May affect ability to drive & operate machinery. Liver disease.