Sir,
The pharmacokinetic and pharmacodynamic results of liberated propofol published by Shah et al. could be inaccurate.[1] They have mentioned in their article that they would carry out studies using appropriate assay methods to assess the same and find the degree of error within a period of 12 months. They have not been able to publish the new data and six previously published articles have been retracted.[1] The assay inaccuracy is limited to propofol kinetics only, and therefore, previously published fospropofol kinetics are unaffected.[2]
Time to achieve Cmax of liberated propofol at 12 and 8 min, the volume of distribution of liberated propofol 5.8 l/kg, and the mean terminal phase half life of 2.06 ± 0.77 h for propofol, described in pharmacokinetics in our article,[3] may be inaccurate. Three references (Schywalsky et al.,[4] Fechner et al.,[5] and Gibiansky et al.[6] ) in our review article[3] have been retracted. Pharmacokinetic data of liberated propofol have been quoted by us from Gibiansky et al only . We wish to bring to your notice that US FDA approval label for fospropofol as on 21-01-2010, which was accessed by the authors on 17-08-2010 and 30-09-2011, about the pharmacokinetics of liberated propofol has not changed till date.[7]
References
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