Aminoglycoside PK Calculator

Parameter Estimation from Two Levels

Elimination Rate Constant (k_e)

k_e = ln(C₁ / C₂)t₂ − t₁

t₁, t₂ = hours after start of infusion

Elimination Half-Life (t_½)

t_½ = 0.693k_e

Extrapolated Peak (C_max)

C_max = C₁e^{−k_e(t₁ − t′)}

t′ = infusion duration (hr)

Extrapolated Trough (C_min)

C_min = C_max · e^{−k_e(τ − t′)}

τ = dosing interval (hr)

Volume of Distribution (V_d)

V_d = (Dose/t′) · (1 − e^−k_et′) C_max · k_e · (1 − e^−k_eτ)

Clearance (Cl_r)

Cl_r = V_d · k_e

L/hr — multiply by 16.67 for mL/min

AUC₂₄

AUC₂₄ = Dosek_e · V_d · 24τ

mg·h/L

Input Parameters

Concentrations & Times Date / Time / Dose

C₁ — First Level (mg/L)

C₂ — Second Level (mg/L)

t₁ — Time of C₁ after start of infusion (hr)

t₂ — Time of C₂ after start of infusion (hr)

Dose Date

Dose Time

Date of C₁

Time of C₁

C₁ Concentration (mg/L)

Date of C₂

Time of C₂

C₂ Concentration (mg/L)

Infusion Duration t' (hr)

Dosing Interval τ (hr)

Total Dose (mg)

Calculated PK Parameters

Enter values and click Calculate to see results.

Concentration–Time Curve

Predicted Concentrations from Dose

Predicted Peak (C_max)

C_max = DoseV_d · k_e · t′ · (1 − e^−k_et′)

Predicted Trough (C_min)

C_min = C_max · e^{−k_e(τ − t′)}

Predicted AUC₂₄

AUC₂₄ = Dosek_e · V_d · 24τ

Back-Calculation: Dose from Target

Dose from AUC Target

Dose = AUC_24,target · k_e · V_d · τ24

Rearrangement of the AUC₂₄ equation above

Dose from Peak Target

Dose = C_max,target · V_d · k_e · t′ 1 − e^−k_et′

Rearrangement of the predicted peak equation above

Patient PK Parameters

Ke (hr⁻¹)

Vd (L)

Infusion Duration t' (hr)

Dosing Interval τ (hr)

Calculation Mode

Target AUC₂₄ (mg·h/L)

Target Peak C_max (mg/L)

Dose (mg)

Optimization Results

Enter parameters and click Calculate.

Aminoglycoside Calculator

Input Parameters

Calculated PK Parameters

Concentration–Time Curve

Patient PK Parameters

Optimization Results

Predicted Concentration–Time Curve