Omeprazole 40mg Vial (MERAZOL) 10s

Indications and Dosage

Intravenous
NSAID-associated ulceration

Adult: 20 mg once daily via slow inj over at least 3 minutes or infusion over 10-30 minutes. Switch to oral therapy as soon possible.

Intravenous
Gastric and duodenal ulcers

Adult: Prophylaxis of rebleeding following therapeutic endoscopy: 80 mg via infusion over 30 minutes, may be followed by 8 mg/hour continuous infusion over 72 hours, then may switch to oral therapy given as 40 mg once daily for 4 weeks.

Intravenous
Gastroesophageal reflux disease

Adult: Erosive reflux oesophagitis: 40 mg once daily. Symptomatic treatment of GERD: 20 mg once daily. Doses are given via slow inj over at least 3 minutes or infusion over 10-30 minutes. Switch to oral therapy as soon possible.
Child: 1-11 years 10 mg once daily. 12-18 years 20 mg once daily. Switch to oral therapy as soon possible.

Oral
NSAID-associated ulceration

Adult: 20 mg once daily for 4-8 weeks.

Oral
Prophylaxis of NSAID-induced ulcers

Adult: 20 or 40 mg once daily for up to 6 months.

Oral
Zollinger-Ellison syndrome

Adult: Initially, 40 mg bid, may be individually adjusted according to response. Usual range: 80-160 mg daily may be increased up to 240 mg daily if necessary. Daily doses >80 mg should be given in 2 divided doses.

Oral
Eradication of H. pylori associated with peptic ulcer disease

Adult: 20 mg bid for 7 days, or 40 mg once daily for 10 days given as a triple therapy in combination with amoxicillin and clarithromycin.
Child: >4 years <30 kg: 10 mg bid; ≥30 kg: 20 mg bid. All doses are given in combination with amoxicillin and clarithromycin for 7 days.

Oral
Gastroesophageal reflux disease

Adult: Erosive reflux oesophagitis: 20 or 40 mg once daily for 4 weeks, may extend for further 4 weeks if necessary. Maintenance (to prevent relapse of healed erosive oesophagitis): 20 mg once daily for up to 6 months. Symptomatic treatment of GERD (without oesophagitis): 20 mg once daily for 4 weeks; assess treatment if symptoms do not resolve after 4 weeks, may extend for further 4 weeks if necessary.
Child: 1-11 years Erosive reflux oesophagitis: ≥10 kg- <20 kg: 10 mg once daily for 8 weeks; ≥20 kg: 10 or 20 mg once daily for 8 weeks. Maintenance (to prevent relapse of healed oesophagitis): 10 mg once daily. Symptomatic treatment of GERD without oesophagitis: 10 mg once daily for up to 8 weeks. 12-18 years Same as adult dose.

Special Patient Group

CYP2C19 is the main enzyme responsible in esomeprazole metabolism and to a lesser extent the CYP3A4 isoenzyme.

CYP2C19 ultrarapid metabolisers (carriers of 2 increased function alleles e.g. *17/*17)
Patient may have insufficient therapeutic response to esomeprazole. Increase esomeprazole dose by 50-100% when used for eradication of H. pylori and monitor for risk of therapeutic failure. For other indications, may also consider increasing the dose by 50-100%.

CYP2C19 poor metabolisers (carriers of loss-of-function allele *2 e.g. *2/*2, *2/*3, *3/*3)
Patient may be exposed to higher esomeprazole levels. However, dosage adjustment may not be necessary. The incidence of this CYP2C19 phenotype varies and is estimated at 3% in Caucasians and 15-20% in Asians.

Currently, recommendations for CYP2C19 genetic testing in esomeprazole treatment have not been provided.

Hepatic Impairment

Severe: Max: 20 mg daily.

Intravenous
Gastric and duodenal ulcers: Severe (Child-Pugh class C): 80 mg via infusion over 30 minutes, may be followed by 4 mg/hour continuous infusion over 72 hours.

Administration

Delayed-Release Cap: Should be taken on an empty stomach. Take 1 hr before meals.
Tab: May be taken with or without food.

Reconstitution

IV inj: Reconstitute vial labelled as 20 mg or 40 mg with 5 mL 0.9% NaCl. IV infusion (10-30 minutes): Reconstitute vial with 5 mL of 0.9% NaCl, lactated Ringer’s inj or 5% dextrose in water, then further dilute to reach final volume of 50 mL. IV infusion (loading dose and continuous infusion): Reconstitute 2 vials labelled as 40 mg with 5 mL normal saline each, then further dilute the 2 vials in 100 mL normal saline.

Contraindications

Concomitant use with rilpivirine, atazanavir, and nelfinavir.

Special Precautions

Patient with gastric malignancy, reduced body stores or risk factors for reduced vitamin B₁₂ absorption, or those at risk of fractures and osteoporosis. Severe renal and hepatic impairment. Children. Pregnancy and lactation. CYP2C19 ultrarapid metabolisers.

Adverse Reactions

Significant: Hypomagnesaemia, osteoporosis-related fractures, fundic gland polyp, subacute cutaneous lupus erythematosus, SLE, acute interstitial nephritis, atrophic gastritis, Clostridium difficile-associated diarrhoea, gastrointestinal infections (e.g. Salmonella, Campylobacter), vitamin B12 deficiency (long-term therapy).
Blood and lymphatic system disorders: Rarely, leucopenia, thrombocytopenia.
Eye disorders: Blurred vision.
Gastrointestinal disorders: Flatulence, diarrhoea, nausea, abdominal pain, vomiting, constipation, xerostomia.
General disorders and admin site conditions: Inj site reactions, fever, malaise.
Hepatobiliary disorders: Increased liver enzymes. Rarely, hepatitis.
Immune system disorders: Rarely, hypersensitivity reactions (e.g. angioedema, anaphylactic shock, urticaria).
Investigations: Altered thyroid hormone levels, increased gastrin, increased serum creatinine.
Metabolism and nutrition disorders: Peripheral oedema. Rarely, hyponatraemia.
Musculoskeletal and connective tissue disorders: Arthralgia, myalgia, weakness.
Nervous system disorders: Headache, dizziness, drowsiness, vertigo, paraesthesia.
Psychiatric disorders: Insomnia, agitation, confusion, depression.
Reproductive system and breast disorders: Very rarely, gynaecomastia.
Respiratory, thoracic and mediastinal disorders: Cough, bronchospasm.
Skin and subcutaneous tissue disorders: Pruritus, rash, dermatitis. Rarely, alopecia.

Pregnancy Category (US FDA)

IV/Parenteral/PO: C

Patient Counseling Information

This drug may cause dizziness and blurred vision, if affected, do not drive or operate machinery.

Monitoring Parameters

Monitor serum Mg levels prior to treatment initiation and periodically thereafter. Assess for signs or symptoms of rebleeding, bone fractures, and Clostridium difficile-associated diarrhoea (CDAD).

Overdosage

Symptoms: Weakness, confusion, headache, drowsiness, tachycardia, nausea, diaphoresis, flushing, dry mouth and other gastrointestinal symptoms. Management: Symptomatic and supportive treatment.

Drug Interactions

Increased risk of digoxin-induced cardiotoxic effects. May diminish the therapeutic effects of clopidogrel. Increased risk of hypomagnesaemia with diuretics. May increase serum concentrations of tacrolimus, methotrexate, cilostazol, and drugs metabolised by CYP2C19 (e.g. diazepam, citalopram, imipramine, phenytoin). May reduce absorption of ketoconazole, itraconazole, Fe salts, erlotinib. Concomitant use with warfarin may increase INR and prothrombin time. Esomeprazole serum levels may be decreased with CYP2C19 or CYP3A4 inducers (e.g. rifampicin) and increased with CYP3A4 inhibitors (e.g. voriconazole, clarithromycin). May prolong elimination half-life of cisapride.
Potentially Fatal: May substantially decrease the serum levels of atazanavir, nelfinavir, or rilpivirine which may lead to the development of drug resistance.

Food Interaction

Decreased serum concentrations with St. John’s wort.

Lab Interference

May increase serum chromogranin A (CgA) levels causing false-positive result in diagnostic test for neuroendocrine tumours.

Action

Description: Esomeprazole, the S-isomer of omeprazole, is a substituted benzimidazole proton pump inhibitor (PPI) that blocks the final step in gastric acid secretion by specific inhibition of H⁺/K⁺-ATPase enzyme system present on the secretory surface of the gastric parietal cells.
Pharmacokinetics:
Absorption: Rapidly absorbed from the gastrointestinal tract. Delayed and reduced absorption with food. Bioavailability: Approx 64% (single dose); approx 89% (repeated dose). Time to peak plasma concentration: Approx 1-2 hours.
Distribution: Plasma protein binding: Approx 97%.
Metabolism: Extensively metabolised in the liver primarily by CYP2C19 isoenzyme to form inactive hydroxy and desmethyl metabolites, and to a lesser extent by CYP3A4 isoenzyme to sulfone metabolite.
Excretion: Mainly via urine (approx 80% as inactive metabolites; <1% as unchanged drug); faeces (20%). Elimination half-life: Approx 1-1.5 hours.

Chemical Structure

Esomeprazole

Source: National Center for Biotechnology Information. PubChem Database. Esomeprazole, CID=9568614, https://pubchem.ncbi.nlm.nih.gov/compound/Esomeprazole (accessed on Jan. 22, 2020)

Storage

Store between 20-25°C. Protect from light and moisture.

MIMS Class

Antacids, Antireflux Agents & Antiulcerants

ATC Classification

A02BC05 – esomeprazole ; Belongs to the class of proton pump inhibitors. Used in the treatment of peptic ulcer and gastro-oesophageal reflux disease (GERD)