// Workers AI · dad joke modeWhat did half-value duration say to its date? You're half the time I'm looking for.
Half-value duration (HVD or HaVD), also known as T50%Cmax, is a pharmacokinetic parameter defined as the time for circulating concentrations to decline to 50% of the peak or maximal concentration (Cmax).[1][2] It was introduced by J. Meier and colleagues in 1974 for description of modified-release drug formulations.[2][3] Related metrics include T75%Cmax and T25%Cmax, among others.[1]
See also
[edit]References
[edit]- 1 2 Endrenyi L, Tothfalusi L (December 2012). "Metrics for the evaluation of bioequivalence of modified-release formulations". AAPS J. 14 (4): 813–819. doi:10.1208/s12248-012-9396-8. PMC 3475860. PMID 22910857.
The peak occupancy time (POT) or plateau time is the time span during which the concentration is at some, clinically specified level (e.g., 25% or 50%) below Cmax thereby yielding the metrics T75%Cmax and T50%Cmax (33). T50%Cmax has also been referred to as the half-value duration (HaVD) (34). These metrics are important for characterizing and comparing concentration profiles of MR formulations and will be considered later. (The notation of HVD is used in the literature to represent the half-value duration. However, the same acronym has been applied in recent years to indicate highly variable drugs. Therefore, the notation HaVD is applied here for the half-value duration.)
- 1 2 Steinijans VW (1990). "Pharmacokinetic characterization of controlled-release formulations". Eur J Drug Metab Pharmacokinet. 15 (2): 173–181. doi:10.1007/BF03190201. PMID 2200687.
- ↑ Meier J, Nüesch E, Schmidt R (October 1974). "Pharmacokinetic criteria for the evaluation of retard formulations". Eur J Clin Pharmacol. 7 (6): 429–432. doi:10.1007/BF00560355. PMID 4155170.