CIRCADIAN CARBAMAZEPINE TOXICITY

Owing to marked fluctuations in plasma concentrations, circadian CNS t oxicity (maximum in the early afternoon) occurred in a 69-year-old fem ale patient being treated with an instant-release formulation of carba mazepine (CBZ). The neurologic syndrome was reversible after administr ation of the same daily dose as sustained-release formulation. This ca se illustrates the importance of correct timing of blood sampling to d etect drug-induced toxicity and of use of sustained-release formulatio ns in antiepileptic therapy with CBZ.