Set CL vs dose and PB
Set 2 PK parameters from 2 points data
Set 3 SS
Set 4 F, R, Dose
Set 5 Infusion
100
CL = 0.5 L/hr given dose 100 mg
if CL = 0.25 L/hr then dose = ? mg
50 mg
100
Cp1 = 10 mg/L, t1 = 8 hr
Cp2 = 5 mg/L, t2 = 16 hr
Half-life = ? hr
8 hr
100
How many dose to get SS?
If drug has half-life 6 hr given every 12 hr
3 doses
100
F (fluctuation) = ?
If drug has half-life 6 hr given every 12 hr
2^(tau/half-life) = 4
100
Ko = ? mg/hr
480 mg/hr
200
Loading dose ? mg
if need Cp = 10 mg/L, Vd = 10 L
100 mg
200
Cp1 = 10 mg/L, t1 = 8 hr
Cp2 = 5 mg/L, t2 = 16 hr
Cpo = ? mg/Lr
20 mg/L
200
How much C at SS (mg/L)?
If 120 mg drug given every 12 hr,
CL = 1 L/hr
10 mg/L
200
R (Accumulation) = ?
If drug has half-life 6 hr given every 12 hr
R = 1 /(1-2^(-tau/half-life))
= 4/3
Note: e^(ln(2)) = 2
200
C at SS = ? mg/L
If Ko = 500 mg/hr, CL = 10 L/hr
50 mg/L
300
Drug A is 90% PB
Which PK parameters will not be changed after adding drug B (PB 99%)?
1. Elimination rate constant (k)
2. Half-life
300
Cp1 = 10 mg/L, t1 = 8 hr
Cp2 = 5 mg/L, t2 = 16 hr
K = ? hr-1
0.087
300
CL =? L/hr
If 120 mg dose q 12 hr, C at SS = 10 mg/L
1 L/hr
300
Loading dose = ?
If 100 mg drug has half-life 6 hr given every 12 hr, R = 4/3
400/3 = 133
300
CL = ? L/hr
If Ko = 500 mg/hr, C at SS = 50 mg/L
10 L/hr
400
Drug A is 90% PB
Which PK parameters will be changed after adding drug B (PB 99%)?
1. Increased Vd (incraesed fu)
2. In creased CL
3. Decreased AUC
4. Decreased Cmax
400
Dose 100 mg
Cp1 = 10 mg/L, t1 = 8 hr
Cp2 = 5 mg/L, t2 = 16 hr
Vd = ? L
Vd = (S)(F)(Dose)/Cp0
Cp0 = 20 mg/L, Dose 100 mg
Vd = 5 L
400
Dose = ? if need C at SS = 20 mg/L (same CL)?
If 120 mg drug given every 12 hr,
get Css 10 mg/L
240 mg
400
If drug has half-life 12 hr,
Need F = 2, should give every ? hr
12 hr
400
Dose ? mg in 0.5 hr
If Ko = 500 mg/hr, Css = 50 mg/L
Need Css = 100 mg/L
500 mg
500
1. zero- หรือ first-order rate of absorption
2. กี่ compartment
1. First-order
2. Two-compartment
500
Dose 100 mg
Cp1 = 10 mg/L, t1 = 8 hr
Cp2 = 5 mg/L, t2 = 16 hr
Duration 12 hr
If dose 200 mg then duration =? hr
12+8 = 20 hr
500
Half-life = hr?
If 120 mg drug given every 12 hr,
Css = 10 mg/L, Vd = 10 L
k= 0.1 hr-1
t1/2 = 7 hr
500
If drug has half-life 12 hr,
Need R = 2, should give every ? hr
12 hr
500
Oral dose = ? mg/day, F= 0.5
If Ko (infusion rate) = 100 mg/hr
4800 mg