A normal-phase column liquid chromatographic assay for fluvoxamine, a recently introduced atypical antidepressant, has been developed. Prior to analysis, aliquots of alkalinized plasma were extracted with n-hexane. These extracts were then injected into a 5-microns Resolve spherical silica column. Fluvoxamine and the internal standard, clovoxamine, were detected at a wavelength of 254 nm. Standard curves were linear over the concentration range 2-400 ng/ml. Acceptable coefficients of variation were obtained for both within-run and day-to-day studies. The estimated limit of detection is 0.5 ng/ml, and selected drugs checked for coadministration show no analytical interference. This assay was used to evaluate the pharmacokinetics of fluvoxamine in rats.