Esomeprazole
Esomeprazole. S-enantiomer of omeprazole — slower CYP2C19 metabolism than the racemate gives modestly higher steady-state AUC. Same H+/K+-ATPase… Oral half-life 1.7 h.
S-enantiomer of omeprazole — slower CYP2C19 metabolism than the racemate gives modestly higher steady-state AUC. Same H+/K+-ATPase mechanism. CYP2C19 inhibitor (clopidogrel DDI relevant).
PK: V 16 L WAS A PLASMA CLEARANCE. The cited abstract states no volume at all; what it states is "Plasma clearance (CL) of esomeprazole decreased from 22 l/h to 16 l/h" — a clearance in litres per hour stored as a volume in litres. A new collision shape. The half-life of 1.5 h was that paper stated TMAX; the real figure is 1.7 h (PMID:11286324, though in elderly subjects at day 5). F corrected 0.7 to the stated 64%, the 40 mg capsule single-dose value; the stored figure was a rounding of the day-5 20 mg SOLUTION arm. NO HUMAN VOLUME EXISTS in any abstract found, so V is dropped and the resolver default overstates it roughly two-fold — logged rather than guessed. THIS IS THE S-ENANTIOMER of omeprazole and the two records are not interchangeable: its bioavailability is about double the racemate. Effect decoupling and the enteric-coat lag apply here exactly as for omeprazole.
Pharmacokinetics
- Oral — t½ 1.7 h · F 64%
- IV — t½ 1.7 h · F 100%
Sources: PMID:11286324