ДоземірClinical dose reference · modeled pharmacokinetics
ENUA
Compare doses

Compare two doses over time

Check how exposure changes between two doses of the same drug

Example drug

Published bioavailability drops from ~60% at 900 mg to ~33% at 3600 mg.

Dose A
Dose B

Find the dosing interval that best reproduces the other curve — the dose and pharmacokinetics stay fixed.

4× the dose → 2× the modeled exposure (less than proportional).
Under linear PK the exposure ratio would equal the dose ratio. The model produces 0.5× of that — describing the behavior for the values entered.
Concentration (mg/L)
Dose A (900 mg)Dose B (3600 mg)
01020304050081624324048Time (h)Concentration (mg/L)
Modeled estimate: Dose A peaks at 11.33 mg/L (AUC 405.8 mg·h/L); Dose B peaks at 22.66 mg/L (AUC 811.6 mg·h/L). Dose B's peak is 2× and its exposure 2× Dose A — less than proportional to the dose change. Full modeled values are in the metrics table below.
Bioavailability vs dose
0.000.250.500.751.00078015602340312039004680F = 0.60F = 0.30Dose (mg)F

Bioavailability F falls as the dose rises — absorption is saturable, so exposure does not scale with dose.

Dose ADose BB / A
Peak (Cmax) mg/L11.3322.662.00×
Time to peak h42.442.41.00×
Exposure (AUC) mg·h/L405.8811.62.00×
Time to steady state h32.032.0—

Dosing-frequency comparison

For this drug, per-dose bioavailability depends on the per-dose amount. Splitting a fixed total daily dose across more administrations changes the modeled exposure. The schedules below split the same total daily dose four ways — these are modeled estimates from the parameters you entered, not dosing advice.

mg/day
Modeled per-schedule bioavailability, daily AUC, and Cmax for the same total daily dose.
SchedulePer dose (mg)F (modeled)Daily AUC (mg·h/L)Cmax (mg/L)
QD (once daily)27000.36140.8711.872
BID (twice daily)13500.51201.2411.191
TID (three times daily)9000.60234.7811.387
QID (four times daily)6750.65256.1211.701

This is a model output, not advice. For this total daily dose the model predicts that splitting it into more frequent doses changes the modeled exposure: daily AUC differs by about 82% between the once-daily and four-times-daily schedules.

These are modeled estimates from the parameters you entered, not dosing advice. Confirm any dose change with a prescriber or pharmacist.

Evidence: 4 of 5 stars — Well-validated method backed by primary clinical evidence.

Modeled estimates from the values you entered. Not a dose recommendation.

Educational PK model — not clinical guidance. Confirm any dose change with a prescriber or pharmacist.