Emergent complications of the newer anticonvulsants.

BACKGROUND: Multiple new anticonvulsants have been introduced recently and they are supplanting the older medications. Whereas the older drugs have well-recognized side effects, both in typical therapeutic doses and in overdosage, the properties of the newer ones are unique and largely unknown to all but sub-specialists. OBJECTIVES: This article gives a concise overview of the potential complications of these new medications in both therapeutic use and overdose. DISCUSSION: Clinically significant side effects of the new anticonvulsants, such as metabolic acidosis from topiramate, autoimmune reactions from lamotrigine, hyponatremia from oxcarbazepine, or psychosis from levitiracetam can cause serious morbidity and mortality if unrecognized. The effects of these medications in overdose are also largely unknown to most emergency physicians. CONCLUSIONS: This article reviews the major potential side effects of the new seizure medications and the treatment of their overdoses for the practicing emergency physician.

Thermochemistry of radicals and molecules relevant to atmospheric chemistry: determination of group additivity values using G3//B3LYP theory.

Thermochemistry of radicals is not as extensively tabulated as that of stable molecular species, even when group additivity schemes are applied. When these radicals contain oxygen or nitrogen atoms, the availability of radical groups is even more limited. Many oxygen- and nitrogen-containing radicals and molecules are present in the atmosphere, and thermochemistry is a valuable component of the development of atmospheric models with predictive capabilities. This paper presents quantum chemical calculations using G3//B3LYP that have been performed to obtain heats of formation, entropies, and heat capacities as a function of the temperature of radicals and molecules from which group additivity values were obtained. Isodesmic and homodesmotic reactions were used to obtain improved estimates of the heats of formation. Thermodynamic property estimates were corrected to account for internal rotations. A total of 323 molecules were studied from which a total of 122 different groups, 21 gauche and cis corrections, and 5 secondary corrections were regressed.