Progressive behavioral changes during chronic lidocaine administration: Relationship to kindling

Chronic, five times weekly administration of lidocaine (60 mg/kg, i.p.) to rats resulted in the progressive development of abnormal eating behavior and seizures. Experimental rats became omniphagic, eating significantly more feces, straw, and gauze than controls. Following an average of 15 lidocaine injections unassociated with seizures, animals began to have major motor convulsions, which then increased in frequency and duration. A pharmacological kindling mechanism is suggested for the progressive effects of lidocaine on behavior and seizures.