Oral suspension: Unpredictable and variable (optimal absorption with a high-fat meal in 4 divided doses; absorption may be sufficient if taken with a nutritional supplement or acidic beverage [eg, ginger ale]).
Tablet (delayed-release): Predictable (preferably administered with food, but absorption is sufficient under fasting conditions)
Distribution: Vd: Oral: 287 L; Injection: ~261 L
Protein binding: >98%; predominantly bound to albumin
Metabolism: Not significantly metabolized; 17% undergoes non-CYP-mediated metabolism, primarily via hepatic glucuronidation into metabolites
Bioavailability:
Oral: Suspension and delayed release tablets are not bioequivalent; higher plasma exposure observed with delayed release tablets
Suspension: Dependent upon gastric pH environment (decreased with higher pH or increased motility) and fed-conditions (increased in high-fat environment)
Delayed release tablets: Dependent upon fed condition: Fasted conditions: 54%; higher under high-fat fed conditions (51% increase in AUC).
Half-life elimination:
Suspension: 35 hours (range: 20 to 66 hours)
Tablets: 26 to 31 hours
Injection: ~27 hours
Time to Peak, Plasma:
Suspension: ~3 to 5 hours
Tablets: ~4 to 5 hours
Excretion: Feces 71% (~66% of the total dose as unchanged drug); urine 13% (<0.2% of the total dose as unchanged drug)