DESCRIPTION
Mechanism of Action
Rabeprazole belongs to a class of antisecretory compounds (substituted benzimidazole proton-pump inhibitors) that do not exhibit anticholinergic or histamine H2-receptor antagonist properties, but suppress gastric acid secretion by inhibiting the gastric H+/K+ATPase at the secretory surface of the gastric parietal cell. Because this enzyme is regarded as the acid (proton) pump within the parietal cell, Rabeprazole has been characterized as a gastric proton-pump inhibitor. Rabeprazole blocks the final step of gastric acid secretion. In gastric parietal cells, Rabeprazole is protonated, accumulates, and is transformed to an active sulfenamide. When studied in vitro, Rabeprazole is chemically activated at pH 1.2 with a half-life of 78 seconds. It inhibits acid transport in porcine gastric vesicles with a half-life of 90 seconds.
Antisecretory Activity
The antisecretory effect begins within one hour after oral administration of 20 mg Rabeprazole. The median inhibitory effect of Rabeprazole on 24 hour gastric acidity is 88% of maximal after the first dose. Rabeprazole 20 mg inhibits basal and peptone meal-stimulated acid secretion versus placebo by 86% and 95%, respectively, and increases the percent of a 24-hour period that the gastric pH>3 from 10% to 65% . This relatively prolonged pharmacodynamic action compared to the short pharmacokinetic half-life (1-2 hours) reflects the sustained inactivation of the H+/K+ATPase.

INDICATIONS
1. Healing of Erosive or Ulcerative GERD
RABIA 20 is indicated for short-term (4 to 8 weeks) treatment in the healing and symptomatic relief of erosive or ulcerative gastroesophageal reflux disease (GERD). For those patients who have not healed after 8 weeks of treatment, an additional 8-week course of RABIA 20may be considered.
2. Maintenance of Healing of Erosive or Ulcerative GERD
RABIA 20is indicated for maintaining healing and reduction in relapse rates of heartburn symptoms in patients with erosive orulcerative gastroesophageal reflux disease (GERD Maintenance). Controlled studies do not extend beyond 12 months.
3. Treatment of Symptomatic GERD
RABIA 20is indicated for the treatment of daytime and nighttime heartburn and other symptoms associated with GERD in adults and adolescents 12 years of age and above.
4. Healing of Duodenal Ulcers
RABIA 20is indicated for short-term (up to four weeks) treatment in the healing and symptomatic relief ofduodenal ulcers. Most patients heal within four weeks.
5. Helicobacter pylori Eradication to Reduce the Risk of Duodenal Ulcer Recurrence
RABIA 20in combination with amoxicillin and clarithromycin as a three drug regimen, is indicated for the treatment of patients withH. pylori infection and duodenal ulcer disease (active or history within the past 5 years) to eradicate H. pylori. Eradication of H. pylorihas been shown to reduce the risk of duodenal ulcer recurrence. In patients who fail therapy, susceptibility testing should be done. If resistance to clarithromycin is demonstrated or susceptibility testing is not possible, alternative antimicrobial therapy should be instituted.
6. Treatment of Pathological Hypersecretory Conditions, Including Zollinger-Ellison Syndrome
RABIA 20 is indicated for the long-term treatment of pathological hypersecretory conditions, including Zollinger- Ellison syndrome

DOSAGE AND ADMINISTRATION
RABIA 20tablets should be swallowed whole. Tabletshould not be chewed, crushed, or split.
RABIA 20can be taken with or without food.
1. Healing of Erosive or Ulcerative GERD
The recommended adult oral dose is one RABIA 20 mg tablet to be taken once daily for four to eight weeks. For those patients who have not healed after 8 weeks of treatment, an additional 8-week course of RABIA 20maybe considered.
2. Maintenance of Healing of Erosive or Ulcerative GERD
The recommended adult oral dose is one RABIA 20 mg tablet to be taken once daily.
3. Treatment of Symptomatic GERD
The recommended adult oral dose is one RABIA 20 mg tablet to be taken once daily for 4 weeks. If symptoms do not resolve completely after 4 weeks, an additional course of treatment may be considered.
4. Healing of Duodenal Ulcers
The recommended adult oral dose is one RABIA 20 mg tablet to be taken once daily after the morning meal for a period up to four weeks. Most patients with duodenal ulcer heal within four weeks. A few patients may require additional therapy to achieve healing.
5. Helicobacter pylori Eradication to Reduce the Risk of Duodenal Ulcer Recurrence
THREE DRUG REGIMEN
Rabeprazole 20 mg Twice daily for 7 days
Amoxicillin 1000 mg Twice daily for 7 days
Clarithromycin 500 mg Twice daily for 7 days
All three medications should be taken twice daily with the morning and evening meals.
It is important that patients comply with the full 7-day regimen.
6. Treatment of Pathological Hypersecretory Conditions Including Zollinger-Ellison Syndrome
The dosage of RABIA 20 mg tablet in patients with pathologic hypersecretory conditions varies with the individual patient. The recommended adult oral starting dose is 60 mg once a day. Doses should be adjusted to individual patient needs and should continue for as long as clinically indicated. Some patients may require divided doses. Doses up to 100 mg QD and 60 mg BID have been administered. Some patients with Zollinger-Ellisonsyndrome have been treated continuously with RABIA 20 mg tablet for up to one year.
7. Short-term Treatment of GERD in Adolescent Patients 12 Years of Age and Above
The recommended oral dose for adolescents 12 years of age and above is 20 mg once daily for up to 8 weeks.
8. Renal Impairment
No dosage adjustment is necessary in patients with renal disease.
9. Hepatic Impairment & Geriatric Use
No dosage adjustment is necessary in patients with mild to moderate hepatic impairment. Administration of Rabeprazole to patients with mild to moderate liver impairment resulted in increased exposure and decreased elimination. Due to lack of clinical data on Rabeprazole in patients with severe hepatic impairment, caution should be exercised in those patients.

CONTRAINDICATIONS
ERabeprazole is contraindicated in patients with known hypersensitivity to rabeprazole, substituted benzimidazoles or to any component of the formulation.