Esomeprazole
Mechanism :
Esomeprazole is a proton pump inhibitor that suppresses gastric acid secretion by specific inhibition of the H+/K+-ATPase in the gastric parietal cell. The S- and R-isomers of omeprazole are protonated and converted in the acidic compartment of the parietal cell forming the active inhibitor, the achiral sulphonamide. By acting specifically on the proton pump, esomeprazole blocks the final step in acid production, thus reducing gastric acidity.
Indication :
- Gastro-esophageal reflux
- Esophageal gastric varices bleeding prophylaxis
- Acid peptic disease resistant to ranitidine
- Helicobacter pylori eradication
Contraindications :
Contraindicated in patients with known hypersensitivity to any component of the formulation or to substituted benzimidazoles.
Dosing :
Oral:
Under 1 month:
Safety and efficacy not established.
1 month to 1 year:
Under 3.5 kg: 2.5 mg orally once everyday for up to 6 weeks.
3.5-7.5 kg:
5 mg orally once every day for up to 6 weeks.
Over 7.5 kg:
10 mg orally once every day for up to 6 weeks.
1-12 years:
10-20 mg orally once a day for up to 8 weeks.
>12 years:
20-40 mg orally once a day for up to 8 weeks.
Intravenous:
Under 1 month:
Safety and efficacy not established.
1 month to 1 year:
0.5 mg/kg IV OD.
Above 1 year, <55 kg:
10 mg IV OD.
Above year, ≥55 kg:
20 mg IV OD.
Adverse Effect :
Headache, diarrhea, nausea, dizziness, flatulence, abdominal pain, constipation, dry mouth.
Interaction :
Warfarin: Changes in prothrombin measures have been received among patients on concomitant warfarin and esomeprazole therapy. Increases in INR and prothrombin time may lead to abnormal bleeding and even death. Patients treated with proton pump inhibitors and warfarin concomitantly may need to be monitored for increases in INR and prothrombin time.
Atazanavir: Concomitant administration of esomeprazole may reduce the plasma levels of atazanavir, thus appropriate clinical monitoring is recommended.
Drugs where gastric pH is important: Esomeprazole inhibits gastric acid secretion. Therefore, esomeprazole may interfere with the absorption of drugs where gastric pH is an important determinant of bioavailability (e.g., ketoconazole, iron salts and digoxin).
Clarithromycin and Amoxicillin: Co-administration of esomeprazole, clarithromycin, and amoxicillin has resulted in increases in the plasma levels of esomeprazole and 14-hydroxyclarithromycin.
Renal Dose :
Dose in Renal Impairment GFR (mL/min)
| 20-50 | Dose as in normal renal function |
| 10-20 | Dose as in normal renal function |
| <10 | Dose as in normal renal function |
Dose in Patients undergoing Renal Replacement Therapies
| CAPD | Unlikely to be dialysed. Dose as in normal renal function |
| HD | Not dialysed. Dose as in normal renal function |
| HDF/High flux | Unlikely to be dialysed. Dose as in normal renal function |
| CAV/VVHD | Unlikely to be dialysed. Dose as in normal renal function |
Hepatic Dose :
Mild to moderate hepatic impairment: No dosage adjustment required.
In adult patients with severe hepatic impairment: do not exceed 20 mg/day.