Linear 1-compartment, bolus | ||
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Parameters | ||

\(CL\) | Clearance. Ratio of the drug’s elimination rate from the body over its circulating concentration, [L/h] | |

\(V\) | Volume of distribution. Ratio of the drug’s amount present in the body over its circulating concentration, [L] | |

\(k_e\) | \(=\frac{CL}{V}\) | |

Equations | ||

Equation: | \(\frac{dC}{dt} = -{k_e} C = -\frac{CL}{V} C\) | |

Initial conditions: | \(C(t_0) = C_{residual} + \frac{D}{V}\) |

Linear 1-compartment, infusion | |
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Parameters | |

\(CL\) | Clearance. Ratio of the drug’s elimination rate from the body over its circulating concentration, [L/h] |

\(V\) | Volume of distribution. Ratio of the drug’s amount present in the body over its circulating concentration, [L] |

\(T_{inf}\) | Infusion time, [h] |

\(k_e\) | \(=\frac{CL}{V}\) |

\(k_0\) | \(=\frac{D}{T_{inf}}\) |

Equations | |

Equation: | \( \begin{align*} \frac{dC}{dt} &= \begin{cases} \frac{k_0}{V} – k_e C , &\text{for $t\leq t_0 + T_{inf}$}\\ - k_e C, &\text{for $t> t_0 + T_{inf}$} \end{cases} \end{align*} \) |

Initial conditions: | \(C(t_0) = C_{residual}\) |

Linear 1-compartment, extravascular | |
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Parameters | |

\(CL\) | Clearance. Ratio of the drug’s elimination rate from the body over its circulating concentration, [L/h] |

\(V\) | Volume of distribution. Ratio of the drug’s amount present in the body over its circulating concentration, [L] |

\(k_a\) | Absorption rate constant. Relative rate constant of the drug’s absorption into the body, [h⁻¹] |

\(F\) | Bioavailability. Fraction of the drug’s administered dose that reaches unchanged the systemic circulation, [%] |

\(k_e\) | \(=\frac{CL}{V}\) |

Equations | |

Equation: | \( \begin{align*} \frac{dC_1}{dt} &= k_a C_2 – k_e C_1 \\ \frac{dC_2}{dt} &= -k_a C_2 \end{align*} \) |

Initial conditions: | \( \begin{align*} C_1(t_0) &= C_{1residual} \\ C_2(t_0) &= C_{2{residual}} + \frac{F D}{V} \end{align*}\) |