- Swallow capsules intact with water. Do not open the capsule and do not administer with liquids other than water.
- Take on an empty stomach at least one hour before a meal [see Clinical Pharmacology (12.3)].
Omeprazole and Sodium Bicarbonate Capsules, 20mg/1100 mg: White to off white powder filled in size "00" hard gelatin capsules with opaque white colored cap and opaque white colored body imprinted "SG" on cap and "363" on body with black ink.
Omeprazole and Sodium Bicarbonate Capsules, 40 mg/1100 mg: White to off white powder filled in size "00" hard gelatin capsules with opaque light blue colored cap and opaque white colored body imprinted "SG" on cap and "364" on body with black ink.
Clinical Trials with Omeprazole
In the U.S. clinical trial population of 465 adult patients, the adverse reactions summarized in Table 3 were reported to occur in 1% or more of patients on therapy with omeprazole.
Table 3: Adverse Reactions Occurring in 1% or More of Adult Patients in US Clinical Trials of Omeprazole Therapy | Omeprazole % (n = 465) | Placebo % (n = 64) | Ranitidine % (n = 195) |
|---|
| Headache | 7 | 6 | 8 |
| Diarrhea | 3 | 3 | 2 |
| Abdominal Pain | 2 | 3 | 3 |
| Nausea | 2 | 3 | 4 |
| Upper Respiratory Infection (URI) | 2 | 2 | 3 |
| Dizziness | 2 | 0 | 3 |
| Vomiting | 2 | 5 | 2 |
| Rash | 2 | 0 | 0 |
| Constipation | 1 | 0 | 0 |
| Cough | 1 | 0 | 2 |
| Asthenia | 1 | 2 | 2 |
| Back Pain | 1 | 0 | 1 |
Table 4 summarizes the adverse reactions that occurred in 1% or more of omeprazole-treated patients from international double-blind and open-label clinical trials in which 2,631 patients and subjects received omeprazole.
Table 4: Adverse Reactions Occurring in 1% or More of Adult Patients in International Clinical Trials of Omeprazole Therapy | Omeprazole % (n = 2631) | Placebo % (n = 120) |
|---|
| Abdominal Pain | 5.2 | 3.3 |
| Nausea | 4.0 | 6.7 |
| Diarrhea | 3.7 | 2.5 |
| Vomiting | 3.2 | 10.0 |
| Headache | 2.9 | 2.5 |
| Flatulence | 2.7 | 5.8 |
| Acid Regurgitation | 1.9 | 3.3 |
| Constipation | 1.5 | 0.8 |
| Asthenia | 1.3 | 0.8 |
Omeprazole
Body as a Whole: Hypersensitivity reactions, including anaphylaxis, anaphylactic shock, angioedema, bronchospasm, urticaria (see also Skin below), fever, pain, fatigue, malaise, and systemic lupus erythematosus.
Cardiovascular: Chest pain or angina, tachycardia, bradycardia, palpitation, elevated blood pressure, and peripheral edema.
Gastrointestinal: Pancreatitis (some fatal), anorexia, irritable colon, flatulence, fecal discoloration, esophageal candidiasis, mucosal atrophy of the tongue, dry mouth, stomatitis, abdominal swelling and fundic gland polyps. Gastroduodenal carcinoids have been reported in patients with Zollinger-Ellison syndrome on long-term treatment with omeprazole. This finding is believed to be a manifestation of the underlying condition, which is known to be associated with such tumors.
Hepatic: Mild and, rarely, marked elevations of liver function tests [ALT (SGPT), AST (SGOT), y-glutamyl transpeptidase, alkaline phosphatase, and bilirubin (jaundice)]. In rare instances, overt liver disease has occurred, including hepatocellular, cholestatic, or mixed hepatitis, liver necrosis (some fatal), hepatic failure (some fatal), and hepatic encephalopathy.
Infections and Infestations: Clostridium difficile- associated diarrhea.
Metabolism and Nutritional Disorders: Hyponatremia, hypoglycemia, hypomagnesemia, and weight gain.
Musculoskeletal: Muscle cramps, myalgia, muscle weakness, joint pain, bone fracture, and leg pain.
Nervous System/Psychiatric: Psychic disturbances including depression, agitation, aggression, hallucinations, confusion, insomnia, nervousness, tremors, apathy, somnolence, anxiety, dream abnormalities; vertigo; paresthesia; and hemifacial dysesthesia.
Respiratory: Epistaxis, pharyngeal pain.
Skin: Severe generalized skin reactions including toxic epidermal necrolysis (TEN; some fatal), Stevens-Johnson syndrome, cutaneous lupus erythematosus and erythema multiforme (some severe); purpura and/or petechiae (some with rechallenge); skin inflammation, urticaria, angioedema, pruritus, photosensitivity, alopecia, dry skin, and hyperhidrosis.
Special Senses: Tinnitus, taste perversion.
Ocular: Blurred vision, ocular irritation, dry eye syndrome, optic atrophy, anterior ischemic optic neuropathy, optic neuritis, and double vision.
Urogenital: Tubulointerstitial nephritis, urinary tract infection, microscopic pyuria, urinary frequency, elevated serum creatinine, proteinuria, hematuria, glycosuria, testicular pain, and gynecomastia.
Hematologic: Rare instances of pancytopenia, agranulocytosis (some fatal), thrombocytopenia, neutropenia, leukopenia, anemia, leukocytosis, and hemolytic anemia have been reported.
Sodium Bicarbonate
Metabolic alkalosis, seizures, and tetany.
Risk Summary
There are no adequate and well-controlled studies with omeprazole and sodium bicarbonate in pregnant women. Omeprazole and sodium bicarbonate capsules contains omeprazole and sodium bicarbonate.
Omeprazole
There are no adequate and well-controlled studies with omeprazole in pregnant women. Available epidemiologic data fail to demonstrate an increased risk of major congenital malformations or other adverse pregnancy outcomes with first trimester omeprazole use. Reproduction studies in rats and rabbits resulted in dose-dependent embryo-lethality at omeprazole doses that were approximately 3.4 to 34 times an oral human dose of 40 mg (based on a body surface area for a 60 kg person).
Teratogenicity was not observed in animal reproduction studies with administration of oral esomeprazole (an enantiomer of omeprazole) magnesium in rats and rabbits during organogenesis with doses about 68 times and 42 times, respectively, an oral human dose of 40 mg esomeprazole or 40 mg omeprazole (based on body surface area for a 60 kg person). Changes in bone morphology were observed in offspring of rats dosed through most of pregnancy and lactation at doses equal to or greater than approximately 34 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole. When maternal administration was confined to gestation only, there were no effects on bone physeal morphology in the offspring at any age (see Data).
Sodium Bicarbonate
Available data with sodium bicarbonate use in pregnant women are insufficient to identify a drug associated risk of major birth defects or miscarriage. Published animal studies report that sodium bicarbonate administered to rats, mice or rabbits during pregnancy did not cause adverse developmental effects in offspring.
The estimated background risks of major birth defects and miscarriage for the indicated population are unknown. All pregnancies have a background risk of birth defect, loss or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2% to 4% and 15% to 20%, respectively.
Data
Human Data
There are no adequate and well-controlled studies with omeprazole and sodium bicarbonate in pregnant women. Four published epidemiological studies compared the frequency of congenital abnormalities among infants born to women who used omeprazole during pregnancy with the frequency of abnormalities among infants of women exposed to H2-receptor antagonists or other controls.
A population-based retrospective cohort epidemiological study from the Swedish Medical Birth Register, covering approximately 99% of pregnancies, from 1995-99, reported on 955 infants (824 exposed during the first trimester with 39 of these exposed beyond first trimester, and 131 exposed after the first trimester) whose mothers used omeprazole during pregnancy. The number of infants exposed in utero to omeprazole that had any malformation, low birth weight, low Apgar score, or hospitalization was similar to the number observed in this population. The number of infants born with ventricular septal defects and the number of stillborn infants was slightly higher in the omeprazole-exposed infants than the expected number in this population.
A population-based retrospective cohort study covering all live births in Denmark from 1996-2009 reported on 1,800 live births whose mothers used omeprazole during the first trimester of pregnancy and 837,317 live births whose mothers did not use any PPI. The overall rate of birth defects in infants born to mothers with first trimester exposure to omeprazole was 2.9% and 2.6% in infants born to mothers not exposed to any PPI during the first trimester.
A retrospective cohort study reported on 689 pregnant women exposed to either H2-blockers or omeprazole in the first trimester (134 exposed to omeprazole) and 1,572 pregnant women unexposed to either during the first trimester. The overall malformation rate in offspring born to mothers with first trimester exposure to omeprazole, an H2-blocker, or were unexposed was 3.6%, 5.5%, and 4.1% respectively.
A small prospective observational cohort study followed 113 women exposed to omeprazole during pregnancy (89% first trimester exposures). The reported rate of major congenital malformations was 4% in the omeprazole group, 2% in controls exposed to non-teratogens, and 2.8% in disease-paired controls. Rates of spontaneous and elective abortions, preterm deliveries, gestational age at delivery, and mean birth weight were similar among the groups.
Several studies have reported no apparent adverse short-term effects on the infant when single-dose oral or intravenous omeprazole was administered to over 200 pregnant women as premedication for cesarean section under general anesthesia.
Animal Data
Omeprazole
Reproductive studies conducted with omeprazole in rats at oral doses up to 138 mg/kg/day (about 34 times an oral human dose of 40 mg on a body surface area basis) and in rabbits at doses up to 69.1 mg/kg/day (about 34 times an oral human dose of 40 mg on a body surface area basis) during organogenesis did not disclose any evidence for a teratogenic potential of omeprazole. In rabbits, omeprazole in a dose range of 6.9 to 69.1 mg/kg/day (about 3.4 to 34 times an oral human dose of 40 mg on a body surface area basis) administered during organogenesis produced dose-related increases in embryo-lethality, fetal resorptions, and pregnancy disruptions. In rats, dose-related embryo/fetal toxicity and postnatal developmental toxicity were observed in offspring resulting from parents treated with omeprazole at 13.8 to 138 mg/kg/day (about 3.4 to 34 times an oral human dose of 40 mg on a body surface area basis), administered prior to mating through the lactation period.
Esomeprazole
The data described below was generated from studies using esomeprazole, an enantiomer of omeprazole. The animal to human dose multiples are based on the assumption of equal systemic exposure to esomeprazole in humans following oral administration of either 40 mg esomeprazole or 40 mg omeprazole.
No effects on embryo-fetal development were observed in reproduction studies with esomeprazole magnesium in rats at oral doses up to 280 mg/kg/day (about 68 times an oral human dose of 40 mg on a body surface area basis) and in rabbits at oral doses up to 86 mg/kg/day (about 42 times an oral human dose of 40 mg of esomeprazole or 40 mg omeprazole on a body surface area basis) administered during organogenesis.
A pre-and postnatal developmental toxicity study in rats with additional endpoints to evaluate bone development were performed with esomeprazole magnesium at oral doses of 14 to 280 mg/kg/day (about 3.4 to 68 times an oral human dose of 40 mg of esomeprazole or 40 mg omeprazole on a body surface area basis). Neonatal/early postnatal (birth to weaning) survival was decreased at doses equal to or greater than 138 mg/kg/day (about 34 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). Body weight and body weight gain were reduced and neurobehavioral or general developmental delays in the immediate post-weaning timeframe were evident at doses equal to or greater than 69 mg/kg/day (about 17 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). In addition, decreased femur length, width and thickness of cortical bone, decreased thickness of the tibial growth plate and minimal to mild bone marrow hypocellularity were noted at doses of esomeprazole magnesium equal to or greater than 14 mg/kg/day (about 3.4 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). Physeal dysplasia in the femur was observed in offspring of rats treated with oral doses of esomeprazole magnesium at doses equal to or greater than 138 mg/kg/day (about 34 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis).
Effects on maternal bone were observed in pregnant and lactating rats in a pre-and postnatal toxicity study when esomeprazole magnesium was administered at oral doses of 14 to 280 mg/kg/day (about 3.4 to 68 times an oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). When rats were dosed from gestational Day 7 through weaning on postnatal Day 21, a statistically significant decrease in maternal femur weight of up to 14% (as compared to placebo treatment) was observed at doses of esomeprazole magnesium equal to or greater than 138 mg/kg/day (about 34 times an oral human dose of 40 mg on a body surface area basis).
A pre-and postnatal development study in rats with esomeprazole strontium (using equimolar doses compared to esomeprazole magnesium study) produced similar results in dams and pups as described above.
A follow-up developmental toxicity study in rats with further time points to evaluate pup bone development from postnatal day 2 to adulthood was performed with esomeprazole magnesium at oral doses of 280 mg/kg/day (about 68 times an oral human dose of 40 mg on a body surface area basis) where esomeprazole administration was from either gestational day 7 or gestational day 16 until parturition. When maternal administration was confined to gestation only, there were no effects on bone physeal morphology in the offspring at any age.
Risk Summary
Available data from the published literature suggest both components of omeprazole and sodium bicarbonate, are present in human milk. There are no clinical data on the effects of omeprazole or sodium bicarbonate on the breastfed infant or on milk production. The developmental and health benefits of breastfeeding should be considered along with the mother's clinical need for omeprazole and sodium bicarbonate and any potential adverse effects on the breastfed infant from omeprazole and sodium bicarbonate or from the underlying maternal condition.
Juvenile Animal Data
Esomeprazole, an enantiomer of omeprazole, was shown to decrease body weight, body weight gain, femur weight, femur length, and overall growth at oral doses about 34 to 68 times a daily human dose of 40 mg esomeprazole or 40 mg omeprazole based on body surface area in a juvenile rat toxicity study. The animal to human dose multiples are based on the assumption of equal systemic exposure to esomeprazole in humans following oral administration of either 40 mg esomeprazole or 40 mg omeprazole.
A 28-day toxicity study with a 14-day recovery phase was conducted in juvenile rats with esomeprazole magnesium at doses of 70 to 280 mg/kg/day (about 17 to 68 times a daily oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis). An increase in the number of deaths at the high dose of 280 mg/kg/day was observed when juvenile rats were administered esomeprazole magnesium from postnatal day 7 through postnatal day 35. In addition, doses equal to or greater than 140 mg/kg/day (about 34 times a daily oral human dose of 40 mg esomeprazole or 40 mg omeprazole on a body surface area basis), produced treatment-related decreases in body weight (approximately 14%) and body weight gain, decreases in femur weight and femur length, and affected overall growth. Comparable findings described above have also been observed in this study with another esomeprazole salt, esomeprazole strontium, at equimolar doses of esomeprazole.
Omeprazole
Reports have been received of overdosage with omeprazole in humans. Doses ranged up to 2400 mg (120 times the usual recommended clinical dose). Manifestations were variable, but included confusion, drowsiness, blurred vision, tachycardia, nausea, vomiting, diaphoresis, flushing, headache, dry mouth, and other adverse reactions similar to those seen in clinical experience with the recommended dosage [see Adverse Reactions (6)]. Symptoms were transient, and no serious clinical outcome has been reported when omeprazole was taken alone. No specific antidote for omeprazole overdosage is known. Omeprazole is extensively protein bound and is, therefore, not readily dialyzable. In the event of overdosage, treatment should be symptomatic and supportive.
Sodium Bicarbonate
Overdosage of sodium bicarbonate can cause electrolyte abnormalities (hypocalcemia, hypokalemia, hypernatremia), metabolic alkalosis, and seizures. Institute supportive care and correct electrolyte abnormalities.
Antisecretory Activity
Results from a pharmacokinetic/pharmacodynamic (PK/PD) study of the antisecretory effect of repeated once-daily dosing of 40 mg and 20 mg of omeprazole and sodium bicarbonate for oral suspension in healthy subjects are shown in Table 8 below.
Table 8: Effect of Omeprazole and Sodium Bicarbonate for Oral Suspension on Intragastric pH, Day 7| Once-Daily Dosage of Omeprazole and Sodium Bicarbonate for Oral Suspension |
|---|
| Parameter | 40 mg omeprazole and 1,680 mg sodium bicarbonate (n = 24) | 20 mg omeprazole and 1,680 mg sodium bicarbonate (n = 28) |
|---|
| Note: Values represent medians. All parameters were measured over a 24-hour period. |
| % Decrease from Baseline for Integrated Gastric Acidity (mmol∙hr/L) | 84% | 82% |
| Coefficient of Variation | 20% | 24% |
| % Time Gastric pH > 4 p < 0.05 20 mg vs. 40 mg (Hours) | 77% (18.6 h) | 51% (12.2 h) |
| Coefficient of Variation | 27% | 43% |
| Median pH | 5.2 | 4.2 |
| Coefficient of Variation | 17% | 37% |
Results from a separate PK/PD study of antisecretory effect on repeated once-daily dosing of 40 mg/1100 mg and 20 mg/1100 mg of omeprazole and sodium bicarbonate capsules in healthy subjects show similar effects in general on the above three PD parameters as those for omeprazole and sodium bicarbonate for oral suspension 40 mg/1680 mg and 20 mg/1680 mg, respectively.
The antisecretory effect lasts longer than would be expected from the very short (1 hour) plasma half-life, apparently due to irreversible binding to the parietal H+/K+ ATPase enzyme.
Enterochromaffin-like (ECL) Cell Effects
Human gastric biopsy specimens have been obtained from more than 3000 patients treated with omeprazole in long-term clinical trials. The incidence of ECL cell hyperplasia in these studies increased with time; however, no case of ECL cell carcinoids, dysplasia, or neoplasia has been found in these patients. These studies are of insufficient duration and size to rule out the possible influence of long-term administration of omeprazole on the development of any premalignant or malignant conditions.
Serum Gastrin Effects
In studies involving more than 200 patients, serum gastrin levels increased during the first 1 to 2 weeks of once-daily administration of therapeutic doses of omeprazole in parallel with inhibition of acid secretion. No further increase in serum gastrin occurred with continued treatment. In comparison with histamine H2-receptor antagonists, the median increases produced by 20 mg doses of omeprazole were higher (1.3 to 3.6-fold vs. 1.1 to 1.8-fold increase). Gastrin values returned to pretreatment levels, usually within 1 to 2 weeks after discontinuation of therapy.
Increased gastrin causes enterochromaffin-like cell hyperplasia and increased serum Chromogranin A (CgA) levels. The increased CgA levels may cause false positive results in diagnostic investigations for neuroendocrine tumors [see Warnings and Precautions (5.11)].
Other Effects
Systemic effects of omeprazole in the central nervous system (CNS), cardiovascular and respiratory systems have not been found to date. Omeprazole, given in oral doses of 30 or 40 mg for 2 to 4 weeks, had no effect on thyroid function, carbohydrate metabolism, or circulating levels of parathyroid hormone, cortisol, estradiol, testosterone, prolactin, cholecystokinin or secretin.
No effect on gastric emptying of the solid and liquid components of a test meal was demonstrated after a single dose of omeprazole 90 mg. In healthy subjects, a single intravenous dose of omeprazole (0.35 mg/kg) had no effect on intrinsic factor secretion. No systematic dose-dependent effect has been observed on basal or stimulated pepsin output in humans. However, when intragastric pH is maintained at 4.0 or above, basal pepsin output is low, and pepsin activity is decreased.
As do other agents that elevate intragastric pH, omeprazole administered for 14 days in healthy subjects produced a significant increase in the intragastric concentrations of viable bacteria. The pattern of the bacterial species was unchanged from that commonly found in saliva. All changes resolved within three days of stopping treatment.
The course of Barrett's esophagus in 106 patients was evaluated in a U.S. double-blind controlled study of omeprazole 40 mg twice daily for 12 months followed by 20 mg twice daily for 12 months or ranitidine 300 mg twice daily for 24 months. No clinically significant impact on Barrett's mucosa by antisecretory therapy was observed. Although neosquamous epithelium developed during antisecretory therapy, complete elimination of Barrett's mucosa was not achieved. No significant difference was observed between treatment groups in development of dysplasia in Barrett's mucosa, and no patient developed esophageal carcinoma during treatment. No significant differences between treatment groups were observed in development of ECL cell hyperplasia, corpus atrophic gastritis, corpus intestinal metaplasia, or colon polyps exceeding 3 mm in diameter.
Absorption
Tables 9 show the systemic exposures and the time reach peak concentration (Tmax) of omeprazole in healthy subjects following administration of omeprazole and sodium bicarbonate capsules on an empty stomach one hour prior to a meal.
Table 9: Arithmetic Mean (CV%) of the Systemic Exposures (Cmax, AUC) and Tmax of Omeprazole after a Single Oral Dose and Multiple Once-Daily Doses of Omeprazole and Sodium Bicarbonate Capsules | 20 mg Omeprazole and Sodium Bicarbonate capsules | 40 mg Omeprazole and Sodium Bicarbonate capsules |
|---|
| Day 1 | Day 7 | % Change (Day 7/Day 1) | Day 1 | Day 7 | % Change (Day 7/Day 1) |
|---|
| n.a.: not applicable |
| Cmax (ng/mL) | 498.1 (50.9) | 679.8 (44.0) | 36 | 1154 (53.0) | 1526 (48.7) | 32 |
Tmax (hr) [min – max] | 0.61 [0.25-1.5] | 0.82 [0.25-1.5] | n.a. | 0.56 [0.25-1.5] | 0.97 [0.25-3.5] | n.a. |
| AUC0-inf AUC0-24h was used on Day 7 (ng∙hr/mL) | 509.7 (60.5) | 1029 (67.9) | 102 | 1882 (120) | 3866 (83.3) | 105 |
Following single or repeated once-daily dosing, peak plasma concentrations (Cmax) of omeprazole from omeprazole and sodium bicarbonate were approximately proportional from 20 to 40 mg doses. A greater than dose proportional increase in mean steady-state AUC (more than three-fold increase on Day 7) was observed when doubling the dose to 40 mg. The bioavailability of omeprazole from omeprazole and sodium bicarbonate increases upon repeated administration. The percent changes in Cmax and AUC between steady-state (Day 7) and single dose (Day 1) indicate omeprazole is a time-dependent autoinhibitor of CYP2C19.
When omeprazole and sodium bicarbonate capsule 40 mg is administered one hour after a meal, the omeprazole AUC is reduced by approximately 27% and 22%, respectively, relative to administration one hour prior to a meal [see Dosage and Administration (2.3)].
Distribution
Omeprazole is bound to plasma proteins. Protein binding is approximately 95%.
Elimination
Metabolism
Omeprazole is extensively metabolized by the cytochrome P450 (CYP) enzyme system. The major part of its metabolism is dependent on the polymorphically expressed CYP2C19 [see Clinical Pharmacology (12.5)], responsible for the formation of hydroxyomeprazole, the major metabolite in plasma. The remaining part is dependent on another specific isoform, CYP3A4, responsible for the formation of omeprazole sulphone.
The mean plasma omeprazole half-life following administration of omeprazole and sodium bicarbonate capsule in healthy subjects is approximately 1 hour (range 0.4 to 4.2 hours), and the total body clearance is 500 to 600 mL/min.
Excretion
Following single-dose oral administration of a buffered solution of omeprazole, the majority of the dose (about 77%) is eliminated in urine as at least six metabolites. Two metabolites have been identified as hydroxyomeprazole and the corresponding carboxylic acid. The remainder of the dose was recoverable in feces. This implies a significant biliary excretion of the metabolites of omeprazole. Three metabolites have been identified in plasma – the sulfide and sulfone derivatives of omeprazole, and hydroxyomeprazole. These metabolites have very little or no antisecretory activity.
Specific Populations
Geriatric Patients
The elimination rate of omeprazole was somewhat decreased in the elderly, and bioavailability was increased. Omeprazole was 76% bioavailable when a single 40 mg oral dose of omeprazole (buffered solution) was administered to healthy elderly subjects versus 58% in young subjects given the same dose. Nearly 70% of the dose was recovered in urine as metabolites of omeprazole, and no unchanged drug was detected. The plasma clearance of omeprazole was 250 mL/min (about half that of young subjects), and its plasma half-life averaged one hour, similar to that of young healthy subjects.
Male and Female Patients
There are no known differences in the absorption or excretion of omeprazole between males and females.
Racial or Ethnic Groups
[see Clinical Pharmacology (12.5)]
Patients with Renal Impairment
In patients with chronic renal impairment (creatinine clearance between 10 and 62 mL/min/1.73 m2), the disposition of omeprazole was very similar to that in healthy subjects, although there was a slight increase in bioavailability. Because urinary excretion is a primary route of excretion of omeprazole metabolites, their elimination slowed in proportion to the decreased creatinine clearance. This increase in bioavailability is not considered to be clinically meaningful.
Patients with Hepatic Impairment
In patients with chronic hepatic disease classified as Child-Pugh Class A (n=3), B (n=4) and C (n=1), the bioavailability of omeprazole increased to approximately 100% compared to healthy subjects, reflecting decreased first-pass effect, and the plasma half-life of the drug increased to nearly 3 hours compared to the in healthy subjects of 0.5 to 1 hour. Plasma clearance averaged 70 mL/min, compared to a value of 500 to 600 mL/min in healthy subjects [see Use in Specific Populations (8.6)].
Drug Interactions Studies
Effect of Omeprazole on Other Drugs
Omeprazole is a time-dependent inhibitor of CYP2C19 and can increase the systemic exposure of co-administered drugs that are CYP2C19 substrates. In addition, administration of omeprazole increases intragastric pH and can alter the systemic exposure of certain drugs that exhibit pH-dependent solubility [see Drug Interactions (7)].
Antiretrovirals
For some antiretroviral drugs, such as rilpivirine, atazanavir and nelfinavir, decreased serum concentrations have been reported when given together with omeprazole [see Drug Interactions (7)].
Rilpivirine: Following multiple doses of rilpivirine (150 mg, daily) and omeprazole (20 mg, daily), AUC was decreased by 40%, Cmax by 40%, and Cmin by 33% for rilpivirine.
Nelfinavir: Following multiple doses of nelfinavir (1250 mg, twice daily) and omeprazole (40 mg daily), AUC was decreased by 36% and 92%, Cmax by 37% and 89% and Cmin by 39% and 75% respectively for nelfinavir and M8.
Atazanavir: Following multiple doses of atazanavir (400 mg, daily) and omeprazole (40 mg, daily, 2 hours before atazanavir), AUC was decreased by 94%, Cmax by 96%, and Cmin by 95%.
Saquinavir: Following multiple dosing of saquinavir/ritonavir (1000/100 mg) twice daily for 15 days with omeprazole 40 mg daily co-administered days 11 to 15.
AUC was increased by 82%, Cmax by 75%, and Cmin by 106%. The mechanism behind this interaction is not fully elucidated. Therefore, clinical and laboratory monitoring for saquinavir toxicity is recommended during concurrent use with PRILOSEC.
Clopidogrel
In a crossover clinical study, 72 healthy subjects were administered clopidogrel (300 mg loading dose followed by 75 mg per day) alone and with omeprazole (80 mg at the same time as clopidogrel) for 5 days. The exposure to the active metabolite of clopidogrel was decreased by 46% (Day 1) and 42% (Day 5) when clopidogrel and omeprazole were administered together.
Results from another crossover study in healthy subjects showed a similar pharmacokinetic interaction between clopidogrel (300 mg loading dose/75 mg daily maintenance dose) and omeprazole 80 mg daily when coadministered for 30 days. Exposure to the active metabolite of clopidogrel was reduced by 41% to 46% over this time period.
In another study, 72 healthy subjects were given the same doses of clopidogrel and 80 mg omeprazole, but the drugs were administered 12 hours apart; the results were similar, indicating that administering clopidogrel and omeprazole at different times does not prevent their interaction [see Warnings and Precautions (5.7), and Drug Interactions (7)].
Mycophenolate Mofetil
Administration of omeprazole 20 mg twice daily for 4 days and a single 1000 mg dose of MMF approximately one hour after the last dose of omeprazole to 12 healthy subjects in a crossover study resulted in a 52% reduction in the Cmax and 23% reduction in the AUC of MPA [see Drug Interactions (7)].
Cilostazol
Omeprazole acts as an inhibitor of CYP2C19. Omeprazole, given in doses of 40 mg daily for one week to 20 healthy subjects in crossover study, increased Cmax and AUC of cilostazol by 18% and 26% respectively. The Cmax and AUC of one of the active metabolites, 3,4-dihydro-cilostazol, which has 4 to 7 times the activity of cilostazol, were increased by 29% and 69%, respectively. Co-administration of cilostazol with omeprazole is expected to increase concentrations of cilostazol and the above mentioned active metabolite [see Drug Interactions (7)].
Diazepam
Concomitant administration of omeprazole 20 mg once daily and diazepam 0.1 mg/kg given intravenously resulted in 27% decrease in clearance and 36% increase in diazepam half-life [see Drug Interactions (7)].
Digoxin
Concomitant administration of omeprazole 20 mg once daily and digoxin in healthy subjects increased the bioavailability of digoxin by 10% (30% in two subjects) [see Drug Interactions (7)].
Effect of Other Drugs on Omeprazole
Voriconazole
Concomitant administration of omeprazole and voriconazole (a combined inhibitor of CYP2C19 and CYP3A4) resulted in more than doubling of the omeprazole exposure. When voriconazole (400 mg every 12 hours for one day, followed by 200 mg once daily for 6 days) was given with omeprazole (40 mg once daily for 7 days) to healthy subjects, the steady-state Cmax and AUC0-24 of omeprazole significantly increased: an average of 2 times (90% CI: 1.8, 2.6) and 4 times (90% CI: 3.3, 4.4), respectively, as compared to when omeprazole was given without voriconazole [see Drug Interactions (7)].
Omeprazole and Sodium Bicarbonate Capsules, 20mg/1100 mg: White to off white powder filled in size "00" hard gelatin capsules with opaque white colored cap and opaque white colored body imprinted "SG" on cap and "363" on body with black ink. They are supplied as:
| NDC: 69367-195-30 | Bottles of 30s |
Omeprazole and Sodium Bicarbonate Capsules, 40 mg/1100 mg: White to off white powder filled in size "00" hard gelatin capsules with opaque light blue colored cap and opaque white colored body imprinted "SG" on cap and "364" on body with black ink. They are supplied as:
| NDC: 69367-196-30 | Bottles of 30s |
Acute Tubulointerstitial Nephritis
Advise the patient to call their healthcare provider immediately if they experience signs and/or symptoms associated with acute tubulointerstitial nephritis [see Warnings and Precautions (5.2)].
Sodium Bicarbonate Buffer Content
Inform patients on a sodium-restricted diet or patients at risk of developing congestive heart failure of the sodium content of omeprazole and sodium bicarbonate capsules (304 mg per capsule).
Advise patients that:
- chronic use of bicarbonate with calcium or milk can cause milk-alkali syndrome
- chronic use of sodium bicarbonate may systemic alkalosis
- increased sodium intake can cause swelling and weight gain.
If any of these occur, instruct patients to contact their healthcare provider [see Warnings and Precautions (5.3)].
Clostridium difficile-Associated Diarrhea
Advise the patient to immediately call their healthcare provider if they experience diarrhea that does not improve [see Warnings and Precautions (5.4)].
Bone Fracture
Advise the patient to report any fractures, especially of the hip, wrist or spine, to their healthcare provider [see Warnings and Precautions (5.5)].
Cutaneous and Systemic Lupus Erythematosus
Advise the patient to immediately call their healthcare provider for any new or worsening of symptoms associated with cutaneous or systemic lupus erythematosus [see Warnings and Precautions (5.6)].
Cyanocobalamin (Vitamin B-12) Deficiency
Advise the patient to report any clinical symptoms that may be associated with cyanocobalamin deficiency to their healthcare provider if they have been receiving omeprazole and sodium bicarbonate for longer than 3 years [see Warnings and Precautions (5.8)].
Hypomagnesemia
Advise the patient to report any clinical symptoms that may be associated with hypomagnesemia to their healthcare provider, if they have been receiving omeprazole and sodium bicarbonate for at least 3 months [see Warnings and Precautions (5.9)].
Drug Interactions
Advise patients to report to their healthcare provider if they start treatment with rilpivirine-containing products, clopidogrel, St. John's wort or rifampin, or if they take high-dose methotrexate [see Contraindications (4), and Warnings and Precautions (5.7, 5.10, 5.12)].
Administration
Instruct patients that:
- Two 20 mg omeprazole and sodium bicarbonate capsules are not interchangeable with one 40 mg omeprazole and sodium bicarbonate capsule.
Administration of Omeprazole and Sodium bicarbonate Capsules
- Instruct patients to swallow omeprazole and sodium bicarbonate capsules intact with water. Do not open the capsule and do not administer with liquids other than water.
- Instruct patients to take omeprazole and sodium bicarbonate capsules on an empty stomach at least one hour before a meal [see Dosage and Administration (2.3)].
Manufactured by:
ScieGen Pharmaceuticals, Inc.
Hauppauge, NY 11788 USA
Manufactured for:
Westminster Pharmaceuticals, LLC
Nashville, TN 37217 USA
All trademarks are the property of their respective owners.
Rev: 1/2021