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Calculators

Each calculator uses an equation from a lesson. The fields start with that lesson's example values.

For learning only. Do not use these results to dose patients.

Half-life

t1/2 = 0.693 x Vd / CL

Elimination rate constant

k = CL / Vd

Absolute bioavailability

F = (AUC oral / dose oral) / (AUC IV / dose IV)

Oral bioavailability from three fractions

F = Fa x Fg x Fh

Loading dose, dose into a vein

Loading dose = C target x Vd

Approach to steady state

Fraction of steady state = 1 - 0.5^n

Accumulation ratio

f = 0.5^(tau / t1/2), R = 1 / (1 - f)
From lesson 6.3 Repeated doses

Daily dose from a target AUC

Dose = CL x target AUC / F