In the above article [Schwab AJ and Pang KS (1999) Drug Metab Dispos27:746–755], two equations were incorrect. On page 750, equations 24 and 25 should be:MTTM=(MTTM,pp+MTTPM,pv)AUCM,ppAUCPM,pvAUCM,ppAUCPM,pv+AUCppAUCM,pv+(MTTpp+MTTM,pv)AUCppAUCM,pvAUCM,ppAUCPM,pv+AUCppAUCM,pv Equation 24VTTM=(VTTM,pp+VTTPM,pv)AUCM,ppAUCPM,pvAUCM,ppAUCPM,pv+AUCppAUCM,pv+(VTTpp+VTTM,pv)AUCppAUCM,pvAUCM,ppAUCPM,pv+AUCppAUCM,pv+(MTTM,pp+MTTPM,pv−MTTpp−MTTM,pv)2AUCM,ppAUCPM,pvAUCppAUCM,pv(AUCM,ppAUCPM,pv+AUCppAUCM,pv)2 Equation 25The calculations were based on the correct equations and not on the previously published equations. The authors regret any confusion or inconvenience this error may have caused.

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