Seizures associated with intoxication and abuse of tramadol.

PURPOSE

To assess the frequency of seizures and patient characteristics associated with tramadol intoxication and abuse in young addicts.

METHODS

Patients with history of tramadol abuse and intoxication were prospectively studied during a 3-year period. The characterstics of patients with seizures and those without seizures were compared.

RESULTS

Fifty-seven patients (mean age 22.3 years [range 16-43 years], 47 males) were included. Tonic/clonic seizures occurred in 31 (54.4%) patients, (26 males and 5 females): single in 14 (45%), multiple in 17 (55%) patients after a tramadol dose ranging from 250-2500 mg. Seizures occurred within 24 h after tramadol intoxication in 26 (84%) patients, and later in 5 (16%) patients. Compared to addicts without seizures, the abusers with seizures were younger (p < 0.05). Both epileptiform and nonepileptiform electroencephalographic patterns were more common in patients with seizures than in patients without seizures, but the differences did not reach statistical significance.

CONCLUSION

The neurotoxicity of tramadol commonly manifests as generalized tonic-clonic seizures occurring most frequently within 24 h after tramadol intake. Seizures were more common in younger abusers with a longer duration of exposure to tramadol and with the combined use of tramadol with alcohol.