Pharmacokinetics
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F  Bioavailability
Fraction of administered dose that reaches systemic circulation

F  Bioavailability formula
 F = AUC(route)/AUC (IV)
 [no units]

Vd
Volume of distribution describes the drug's ability to distribute from blood throughout the body

Vd formula
 Vd(apparent) = amount of drug in body/ (Cp)
 [L/kg]

Cp
Concentration of drug in plasma

Elimination
Amount of drug removed from body per unit time

Elimination formula
 Amount of drug removed from body/time
 [mg/hr]

Cl
Clearance is the amount of plasma from which the "total body" can remove the drug per unit time

Cl formula
 Cl = rate of elimination / (Cp)
 [L/hr]

t1/2
Half life is the time it takes form plasma concentration of drug to reach 1/2 it's original concentration at time zero

t1/2 formula
 t1/2 = 0.693 * Vd / Cl
 [time units]

LD  loading dose
LD = Vd* Cp / F

MD  maintenance dose
MD= Cl* Cp / F

How many 1/2 lives to steady state (1st order)
~45

Drugs with zero order kinetics

CYP450 Inducers
 Phenytoin CYP2C810
 Rifampin CYP2C810
 St. John's Wort CYP3A

CYP450 Inhibitors
 Ketoconazole CYP3A
 Erythromycin CYP3A
 Grapefruit Juice CYP3A