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nlmixr2autoinit (version 1.0.0)

get_hf: Estimate half-life from pooled pharmacokinetic data

Description

Estimates the terminal half-life of a drug using pooled pharmacokinetic data. The method supports analysis based on first-dose, repeated-dose, or combined dosing profiles.

Usage

get_hf(dat, dose_type = "first_dose", pooled = NULL, verbose = TRUE, ...)

Value

A list containing individual and median half-life estimates for first-dose, repeated-dose, and combined dosing profiles.

Arguments

dat

A data frame containing raw time–concentration data in the standard nlmixr2 format.

dose_type

Specifies the dosing context of the pharmacokinetic observations. Classified as:

  • first_dose: observations occur only after the initial administration

  • repeated_doses: observations occur only after multiple administrations or at steady state

  • combined_doses: observations include both first-dose and repeated-dose intervals

pooled

Optional pooled data object generated by get_pooled_data. If not provided, pooled data are automatically created using the input dataset.

verbose

Logical; if TRUE (default), progress and completion messages are printed to the console. Set to FALSE to suppress all informational messages, for example when running automated scripts or tests.

...

Additional arguments passed to bin.time for pooling operations or to find_best_lambdaz for elimination slope estimation.

Author

Zhonghui Huang

Details

The function estimates terminal half-life using the following procedure:

  • Generate or use existing pooled pharmacokinetic data

  • Identify the terminal phase using elimination slope estimation

  • Calculate the terminal elimination rate constant (lambda_z)

  • Derive half-life using:

$$ t_{1/2} = \frac{\log(2)}{\lambda_z} $$

See Also

get_pooled_data, bin.time, find_best_lambdaz

Examples

Run this code
dat <- Bolus_1CPT
dat <- processData(dat)$dat
get_hf(dat, dose_type = "combined_doses")

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