A randomized, pharmacokinetic and pharmacodynamic, cross-over study of duodenal or jejunal administration compared to nasogastric administration of omeprazole suspension in patients at risk for stress ulcers.
OBJECTIVE
The aim of this study was to characterize absorption and pH control of simplified omeprazole suspension (SOS), 2 mg/ml in 8.4% sodium bicarbonate, administered via the nasogastric versus jejunal or duodenal route.


METHODS
Nine critically ill surgical patients, NPO and mechanically ventilated, were enrolled in this randomized cross-over study. Patients received a single 40 mg dose of SOS by the nasogastric and either the jejunal or duodenal route. Twenty-four-hour continuous intragastric pH monitoring was performed during the study period. Sequential blood samples were collected over 24 h to characterize SOS absorption and pharmacokinetic parameters.


RESULTS
Nasogastric administration of SOS resulted in lower maximum mean +/- SD serum concentrations compared to jejunal/duodenal dosing (0.970 +/- 0.436 vs 1.833 +/- 0.416 microg/ml, p = 0.006). SOS absorption was significantly slower when administered via nasogastric tube (108.3 +/- 42.0 vs 12.1 +/- 7.9 min, p < 0.001). However, all routes of administration resulted in similar SOS area under the serum concentration-time curves (AUC(0-infinity)) (415.1 +/- 291.8 vs 396.7 +/- 388.1 microg x min/ml, p = 0.91) [corrected]. Mean intragastric pH values remained >4 at 1 h after SOS administration and remained >4 for the entire 24-h study (6.32 +/- 1.04, 5.57 +/- 1.15, nasogastric vs jejunal/duodenal, p = 0.015), regardless of administration route.


CONCLUSIONS
In critically ill surgical patients, pharmacokinetic parameters and subsequent pH control after the administration of SOS are similar by the jejunal, nasogastric, or duodenal route. SOS suspension offers an alternative acid control measure when patients are unable to take oral medications, yet have an enteral tube in place.
Department of Surgery, School of Medicine, University of Missouri-Columbia, USA.
J O
JO
Phillips
K M
KM
Olsen
J A
JA
Rebuck
N J
NJ
Rangnekar
B W
BW
Miedema
M H
MH
Metzler
D000328:Adult; D000897:Anti-Ulcer Agents / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000494:pharmacology / Q000627:therapeutic use; D016638:Critical Illness; D018592:Cross-Over Studies; D004386:Duodenum; D005260:Female; D006801:Humans; D007441:Intubation, Gastrointestinal; D007583:Jejunum; D008297:Male; D009853:Omeprazole / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000494:pharmacology / Q000627:therapeutic use; D010437:Peptic Ulcer / Q000209:etiology / Q000517:prevention & control*; D013312:Stress, Physiological / Q000150:complications*
D000897:Anti-Ulcer Agents; D009853:Omeprazole