Meprazol

Overdose

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There is limited information available on the effects of overdoses of Meprazol in humans. In literature, doses of up to 560 mg have been described, and occasional reports have been received when single oral doses have been reached of up to 2,400 mg Meprazol (120 times the usual recommended clinical dose). Nausea, vomiting, dizziness, abdominal pain, diarrhoea and headache have been reported. Also apathy, depression and confusion have been described in single cases.

The symptoms described in connection with Meprazol overdose have been transient, and no serious outcome has been reported. The rate of elimination was unchanged (first order kinetics) with increased doses. Treatment, if needed, is symptomatic.

There is limited information available on the effects of overdoses of omeprazole in humans. In the literature, doses of up to 560 mg have been described, and occasional reports have been received when single oral doses have reached up to 2,400 mg omeprazole (120 times the usual recommended clinical dose). Nausea, vomiting, dizziness, abdominal pain, diarrhoea and headache have been reported. Also apathy, depression and confusion have been described in single cases.

The symptoms described have been transient, and no serious outcome has been reported. The rate of elimination was unchanged (first order kinetics) with increased doses. Treatment, if needed, is symptomatic.

Meprazol price

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However, we will provide data for each active ingredient

Contraindications

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Meprazol like other proton pump inhibitors (PPIs) must not be used concommitantly with nelfinavir.

Omeprazole like other proton pump inhibitors (PPIs) must not be used concomitantly with nelfinavir.

Incompatibilities

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Not applicable.

Not applicable.

Undesirable effects

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The most common side effects (1-10% of patients) are headache, abdominal pain, constipation, diarrhoea, flatulence and nausea/vomiting.

The following adverse drug reactions have been identified or suspected in the clinical trials programme for Meprazol and post-marketing. None was found to be dose-related.

Adverse reactions listed below are classified according to the frequency and System Organ Class (SOC). Frequency categories are defined according to the following convention:

- very common (>1/10)

- common (>1/100 to<1/10)

- uncommon (>1/1,000 -to <1/100)

- rare (>1/10,000 to <1/1,000)

- very rare (<1/10,000)

- not known (cannot be estimated from the available data)

SOC/ Frequency

Adverse reaction

Blood and lymphatic system disorders

Rare:

Leukopenia, thrombocytopenia

Very rare:

Pancytopenia, agranulocytosis

Immune system disorders

Rare:

Hypersensitivity reactions e.g. fever, angioedema and anaphylactic reaction/ shock

Metabolism and nutrition disorders

Rare:

Hyponataemia

Not Known:

Hypomagneseamia; severe hypomagnesaemia may result in hypocalcaemia

Hypomagnesaemia may also be associated with hypokalaemia.

Psychiatric disorders

Uncommon:

Insomnia

Rare:

Agitation, confusion, depression

Very Rare:

Aggression, hallucinations.

Nervous system disorders

Common:

Headache

Uncommon:

Dizziness, paresthesia, somnolence

Rare:

Taste disturbance

Eye disorders

Rare:

Blurred vision

Ear and labyrinth disorders

Uncommon:

Vertigo

Respiratory, thoracic and mediastinal disorders

Rare:

Bronchospasm

Gastrointestinal disorders

Common:

Abdominal pain, constipation, diarrhoea, flatulence, nausea and vomiting fundic gland polyps (benign)

Rare:

Dry mouth, stomatitis, gastrointestinal candidiasis

Not known:

Microscopic colitis

Hepatobiliary disorders

Uncommon:

Increased liver enzymes

Rare:

Hepatitis with or without jaundice

Very Rare:

Hepatic failure, encephalopathy in patients with pre-existing liver disease

Skin and subcutaneous tissue disorders

Uncommon:

Dermatitis, pruritus, rash, urticaria

Rare:

Alopecia, photosensitivity

Very Rare:

Erythema multiforme,

Stevens-Johnsonsyndrome, toxic epidermal necrolysis (TEN)

Not known

Subacute cutaneous lupus erythematosus

Musculoskeletal and connective tissue disorders

Uncommon:

Fracture of the hip, wrist or spine

Rare:

Arthralgia, myalgia

Very Rare:

Muscular weakness

Renal and urinary disorders:

Rare:

Interstitial nephritis

Reproductive System and breast disorders:

Very Rare:

Gynaecomastia

General disorders and administration site conditions

Uncommon:

Malaise, peripheral oedema

Rare:

Increased sweating.

Paediatric Population

The safety of Meprazol has been assessed in a total of 310 children aged 0 to 16 years with acid-related disease. There are limited long term safety data from 46 children who received maintenance therapy of Meprazol during a clinical study for severe erosive oesophagitis for up to 749 days. The adverse event profile was generally the same as for adults in short- as well as in long-term treatment. There are no long term data regarding the effects of Meprazol treatment on puberty and growth.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme at: www.mhra.gov.uk/yellowcard.

Summary of the safety profile

The most common side effects (1-10% of patients) are headache, abdominal pain, constipation, diarrhoea, flatulence and nausea/vomiting.

Tabulated list of adverse reactions

The following adverse drug reactions have been identified or suspected in the clinical trials programme for omeprazole and post-marketing. None was found to be dose-related. Adverse reactions listed below are classified according to frequency and System Organ Class (SOC). Frequency categories are defined according to the following convention: Very common (> 1/10), Common (> 1/100 to < 1/10), Uncommon (> 1/1,000 to < 1/100), Rare (> 1/10,000 to < 1/1,000), Very rare (< 1/10,000), Not known (cannot be estimated from the available data).

SOC/frequency

Adverse reaction

Blood and lymphatic system disorders

Rare:

Leukopenia, thrombocytopenia

Very rare:

Agranulocytosis, pancytopenia

Immune system disorders

Rare:

Hypersensitivity reactions e.g. fever, angioedema and anaphylactic reaction/shock

Metabolism and nutrition disorders

Rare:

Hyponatraemia

Not known:

Hypomagnesaemia; severe hypomagnesaemia may result in hypocalcaemia.

Hypomagnesaemia may also be associated with hypokalaemia.

Psychiatric disorders

Uncommon:

Insomnia

Rare:

Agitation, confusion, depression

Very rare:

Aggression, hallucinations

Nervous system disorders

Common:

Headache

Uncommon:

Dizziness, paraesthesia, somnolence

Rare:

Taste disturbance

Eye disorders

Rare:

Blurred vision

Ear and labyrinth disorders

Uncommon:

Vertigo

Respiratory, thoracic and mediastinal disorders

Rare:

Bronchospasm

Gastrointestinal disorders

Common:

Abdominal pain, constipation, diarrhoea, flatulence, nausea/vomiting, fundic gland polyps (benign)

Rare:

Dry mouth, stomatitis, gastrointestinal candidiasis

Not known:

Microscopic colitis

Hepatobiliary disorders

Uncommon:

Increased liver enzymes

Rare:

Hepatitis with or without jaundice

Very rare:

Hepatic failure, encephalopathy in patients with pre-existing liver disease

Skin and subcutaneous tissue disorders

Uncommon:

Dermatitis, pruritus, rash, urticaria

Rare:

Alopecia, photosensitivity

Very rare:

Erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis (TEN)

Not known:

Subacute cutaneous lupus erythematosus

Musculoskeletal and connective tissue disorders

Uncommon:

Fracture of the hip, wrist or spine

Rare:

Arthralgia, myalgia

Very rare:

Muscular weakness

Renal and urinary disorders

Rare:

Interstitial nephritis

Reproductive system and breast disorders

Very rare:

Gynaecomastia

General disorders and administration site conditions

Uncommon:

Malaise, peripheral oedema

Rare:

Increased sweating

Paediatric population

The safety of omeprazole has been assessed in a total of 310 children aged 0 to 16 years with acid-related disease. There are limited long-term safety data from 46 children who received maintenance therapy of omeprazole during a clinical study for severe erosive oesophagitis for up to 749 days. The adverse event profile was generally the same as for adults in short- as well as in long-term treatment. There are no long-term data regarding the effects of omeprazole treatment on puberty and growth.

Reporting of suspected adverse reactions

Reporting suspected adverse reactions after authorisation of the medicinal product is important. It allows continued monitoring of the benefit/risk balance of the medicinal product. Healthcare professionals are asked to report any suspected adverse reactions via the Yellow Card Scheme website: www.mhra.gov.uk/yellowcard.

Preclinical safety data

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Gastric ECL-cell hyperplasia and carcinoids have been observed in life-long studies in rats treated with Meprazol. These changes are the result of sustained hypergastrinaemia secondary to acid inhibition. Similar findings have been made after treatment with H2-receptor antagonists, proton pump inhibitors and after partial fundectomy. Thus, these changes are not from a direct effect of any individual active substance.

Gastric ECL-cell hyperplasia and carcinoids, have been observed in life-long studies in rats treated with omeprazole. These changes are the result of sustained hypergastrinaemia secondary to acid inhibition. Similar findings have been made after treatment with H2-receptor antagonists, proton pump inhibitors and after partial fundectomy. Thus, these changes are not from a direct effect of any individual active substance.

Pharmacotherapeutic group

Capsules; Enteric-coated capsules; Lyophilizate for the preparation of a solution for infusions; Pellets; Semi-finished pellets; Substance-pelletsGastro-resistant capsule, hard; Powder and solvent for solution for injection; Powder for solution for infusionProton pump inhibitors, ATC-code: A02BC01Drugs for acid-related disorders, proton pump inhibitors, ATC code: A02BC01

Pharmacodynamic properties

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Pharmacotherapeutic group: Proton pump inhibitors, ATC-code: A02BC01

Mechanism of Action:

Meprazol, a racemic mixture of two enantiomers, reduces gastric acid secretion through a highly targeted mechanism of action. It is a specific inhibitor of the acid pump in the parietal cell. It is rapidly acting and provides control through reversible inhibition of gastric acid secretion with once daily dosing.

Meprazol is a weak base and is concentrated and converted to the active form in the highly acidic environment of the intracellular canaliculi within the parietal cell, where it inhibits the enzyme H+, K+-ATPase - the acid pump. This effect on the final step of gastric acid formation process is dose-dependent and provides for highly effective inhibition of both basal acid secretion and stimulated acid secretion, irrespective of stimulus.

Pharmacodynamic effects:

All pharmacodynamic effects observed can be explained by the effect of Meprazol on acid secretion.

Clinical Efficacy and Safety:

Effect on gastric acid secretion:

Oral dosing with Meprazol once daily provides for rapid and effective inhibition of daytime and night-time gastric acid secretion with maximum effect being achieved within 4 days of treatment. With Meprazol 20mg, a mean decrease of at least 80% in 24-hour intragastric acidity is then maintained on duodenal ulcer patients, with the mean decrease in peak acid output after pentagastrin stimulation being about 70% 24 hours after dosing.

Oral dosing with Meprazol 20mg maintains an intragastric pH of > 3 for a mean time of 17 hours of the 24-hour period in duodenal ulcer patients.

As a consequence of reduced acid secretion and intragastric acidity, Meprazol dose-dependently reduces/normalizes acid exposure of the esophagus in patients with gastro-esophageal reflux disease. The inhibition of acid secretion is related to the area under the plasma concentration-time curve (AUC) of Meprazol and not the actual plasma concentration at a given time.

No tachyphylaxis has been observed during treatment with Meprazol.

Effect on H. pylori

H. pylori is associated with peptic ulcer disease, including duodenal and gastric ulcer disease. H. pylori is a major factor in the development of gastritis. H. pylori together with gastric acid are major factors in the development of peptic ulcer disease. H. pylori is a major factor in the development of atrophic gastritis which is associated with an increased risk of developing gastric cancer.

Eradication of H. pylori with Meprazol and antimicrobials is associated with high rates of healing and long-term remission of peptic ulcers.

Dual therapies have been tested and have been found to be less effective than triple therapies. They could however be considered in cases where known hypersensitivity precludes the use of any triple combination.

Other effects related to acid inhibition

During long-term treatment gastric glandular cysts have been reported in somewhat increased frequency. These changes are a physiological consequence of pronounced inhibition of acid secretion, are benign and appear to be reversible.

Decreased gastric acidity due to any means including proton pump inhibitors, increases gastric count of bacteria normally present in the gastrointestinal tract. Treatment with acid reducing drugs may lead to slightly increased risk of gastrointestinal infections such as Salmonella and Campylobacter and, in hospitalized patients, possibly also Clostridium difficile..

During treatment with antisecretory medicinal products, serum gastrin increases in response to the decreased acid secretion. Also CgA increases due to decreased gastric acidity. The increased CgA level may interfere with investigations for neuroendocrine tumours.

Available published evidence suggests that proton pump inhibitors should be discontinued between 5 days and 2 weeks prior to CgA measurements. This is to allow CgA levels that might be spuriously elevated following PPI treatment to return to reference range.

An increased number of ECL cells possibly related to the increased serum gastrin levels, have been observed in some patients (both children and adults) during long term treatment with Meprazol. The findings are considered to be of no clinical significance.

Paediatric population

In a non-controlled study in children (1 to 16 years of age) with severe reflux esophagitis, Meprazol at doses of 0.7 to 1.4 mg/kg improved esophagitis level in 90 % of the cases and significantly reduced reflux symptoms. In a single-blind study, children aged 0-24 months with clinically diagnosed gastro-esophageal reflux disease were treated with 0.5, 1.0 or 1.5 mg Meprazol/kg. The frequency of vomiting/regurgitation episodes decreased by 50 % after 8 weeks of treatment irrespective of the dose.

Eradication of Helicobacter pylori in children

A randomised, double-blind clinical study (Heliot study) concluded that Meprazol in combination with two antibiotics (amoxicillin and clarithromycin) was safe and effective in the treatment of H. pylori infection in children of 4 years old and above with a gastritis: H. pylori eradication rate: 74 % (23/31 patients) with Meprazol + amoxicillin + clarithromycin versus 9.4 % (3/32 patients) with amoxicillin + clarithromycin. However, there was no evidence of clinical benefit demonstrated regarding dyspeptic symptoms. This study does not support any information for children aged less than 4 years old.

Pharmacotherapeutic group: Drugs for acid-related disorders, proton pump inhibitors, ATC code: A02BC01

Mechanism of action

Omeprazole, a racemic mixture of two enantiomers reduces gastric acid secretion through a highly targeted mechanism of action. It is a specific inhibitor of the acid pump in the parietal cell. It is rapidly acting and provides control through reversible inhibition of gastric acid secretion with once daily dosing.

Omeprazole is a weak base and is concentrated and converted to the active form in the highly acidic environment of the intracellular canaliculi within the parietal cell, where it inhibits the enzyme H+ K+-ATPase - the acid pump. This effect on the final step of the gastric acid formation process is dose-dependent and provides for highly effective inhibition of both basal acid secretion and stimulated acid secretion, irrespective of stimulus.

Pharmacodynamic effects

All pharmacodynamic effects observed can be explained by the effect of omeprazole on acid secretion.

Effect on gastric acid secretion

Oral dosing with omeprazole once daily provides for rapid and effective inhibition of daytime and night-time gastric acid secretion with maximum effect being achieved within 4 days of treatment. With omeprazole 20 mg, a mean decrease of at least 80% in 24-hour intragastric acidity is then maintained in duodenal ulcer patients, with the mean decrease in peak acid output after pentagastrin stimulation being about 70% 24 hours after dosing.

Oral dosing with omeprazole 20 mg maintains an intragastric pH of > 3 for a mean time of 17 hours of the 24-hour period in duodenal ulcer patients.

As a consequence of reduced acid secretion and intragastric acidity, omeprazole dose-dependently reduces/normalizes acid exposure of the oesophagus in patients with gastro-oesophageal reflux disease.

The inhibition of acid secretion is related to the area under the plasma concentration-time curve (AUC) of omeprazole and not to the actual plasma concentration at a given time.

No tachyphylaxis has been observed during treatment with omeprazole.

Effect on H. pylori

H. pylori is associated with peptic ulcer disease, including duodenal and gastric ulcer disease. H. pylori is a major factor in the development of gastritis. H. pylori together with gastric acid are major factors in the development of peptic ulcer disease. H. pylori is a major factor in the development of atrophic gastritis which is associated with an increased risk of developing gastric cancer.

Eradication of H. pylori with omeprazole and antimicrobials is associated with, high rates of healing and long-term remission of peptic ulcers.

Dual therapies have been tested and found to be less effective than triple therapies. They could, however, be considered in cases where known hypersensitivity precludes use of any triple combination.

Other effects related to acid inhibition

During long-term treatment gastric glandular cysts have been reported in a somewhat increased frequency. These changes are a physiological consequence of pronounced inhibition of acid secretion, are benign and appear to be reversible.

Decreased gastric acidity due to any means including proton pump inhibitors, increases gastric counts of bacteria normally present in the gastrointestinal tract. Treatment with acid-reducing drugs may lead to slightly increased risk of gastrointestinal infections such as Salmonella and Campylobacter and, in hospitalised patients, possibly also Clostridium difficile.

During treatment with antisecretory medicinal products, serum gastrin increases in response to the decreased acid secretion. Also CgA increases due to decreased gastric acidity. The increased CgA level may interfere with investigations for neuroendocrine tumours. Available published evidence suggests that proton pump inhibitors should be discontinued between 5 days and 2 weeks prior to CgA measurements. This is to allow CgA levels that might be spuriously elevated following PPI treatment to return to reference range.

An increased number of ECL cells possibly related to the increased serum gastrin levels, have been observed in some patients (both children and adults) during long term treatment with omeprazole. The findings are considered to be of no clinical significance.

Paediatric population

In a non-controlled study in children (1 to 16 years of age) with severe reflux oesophagitis, omeprazole at doses of 0.7 to 1.4 mg/kg improved oesophagitis level in 90% of the cases and significantly reduced reflux symptoms. In a single-blind study, children aged 0-24 months with clinically diagnosed gastro-oesophageal reflux disease were treated with 0.5, 1.0 or 1.5 mg omeprazole/kg. The frequency of vomiting/regurgitation episodes decreased by 50% after 8 weeks of treatment irrespective of the dose.

Eradication of H. pylori in children

A randomised, double blind clinical study (Héliot study) concluded that omeprazole in combination with two antibiotics (amoxicillin and clarithromycin), was safe and effective in the treatment of H. pylori infection in children age 4 years old and above with gastritis: H. pylori eradication rate: 74.2% (23/31 patients) with omeprazole + amoxicillin + clarithromycin versus 9.4% (3/32 patients) with amoxicillin + clarithromycin. However, there was no evidence of any clinical benefit with respect to dyspeptic symptoms. This study does not support any information for children aged less than 4 years.

Pharmacokinetic properties

Capsules; Enteric-coated capsules; Lyophilizate for the preparation of a solution for infusions; Pellets; Semi-finished pellets; Substance-pelletsGastro-resistant capsule, hard; Powder and solvent for solution for injection; Powder for solution for infusion

Absorption

Meprazol is acid labile and is therefore administered orally as enteric-coated granules in hard-gelatin capsules. Absorption of Meprazol is rapid, with peak-plasma levels occurring 1-2 hours after the dose. Absorption of Meprazol takes place in the small intestine and is usually completed within 3-6 hours. Concomitant intake of food has no influence on the bioavailability. The systemic availability (bioavailability) from a single oral dose of Meprazol is approximately 40%. After repeated once-daily administration, the bioavailability increases to about 60%.

Distribution

The apparent volume of distribution in healthy subjects is approximately 0.3l/kg body weight. Meprazol is 97% protein bound.

Biotransformation

Meprazol is completely metabolised, by the cytochrome P450 system (CYP). The major part of metabolism is dependent on the polymorphically expressed CYP 2C19 responsible for the formation of hydroxyMeprazol, the major metabolite in plasma. The remaining part is dependent on another specific isoform, CYP3A4, responsible for the formation of Meprazol Sulphone. As a consequence of high affinity of Meprazol to CYP 2C19, there is the potential for competitive inhibition and metabolic drug-drug interactions with other substrates for CYP 2C19. However due to low affinity to CYP3A4, Meprazol has no potential to inhibit the metabolism of other CYP3A4 substrates. In addition Meprazol lacks an inhibitory effect on the main CYP enzymes.

Approximately 3% of the Caucasian population and 15-20% of the Asian population lack a functional CYP 2C19 enzyme and are called poor metabolisers. In such individuals the metabolism of Meprazol is probably mainly catalysed by CYP3A4. After repeated once-daily administration of 20mg Meprazol the mean AUC was 5 to 10 times higher in poor metabolisers than in subjects having a functional CYP2C19 enzyme (extensive metabolisers). Mean peak plasma concentrations were also higher, by 3 to 5 times. These findings have no implications for the posology of Meprazol.

Elimination

The plasma elimination half life of Meprazol is usually shorter than one hour both after single and repeated oral once daily dosing. Meprazol is completely eliminated from plasma between doses with no tendency for accumulation during once daily administration. Almost 80% of an oral dose of Meprazol is excreted as metabolites in the urine, the remainder in the faeces, primarily originating from bile secretion.

The AUC of Meprazol increases with repeated administration. This increase is dose-dependent and results in a non-linear dose-AUC relationship after repeated administration. This time- and dose- dependency is due to a decrease of first pass metabolism and systemic clearance probably caused by an inhibition of the CYP2C19 enzyme by Meprazol and /or it's metabolites (e.g. the sulphone).

No metabolite has been found to have any effect on gastric acid secretion.

Special Populations

Impaired hepatic function

The metabolism of Meprazol in patients with liver dysfunction is impaired, resulting in an increased AUC. Meprazol has not shown any tendency to accumulate with once-daily dosing.

Impaired renal function

The pharmacokinetics of Meprazol, including systemic bioavailability and elimination rate, are unchanged in patients with reduced renal function.

Elderly

The metabolism rate of Meprazol is somewhat reduced in elderly subjects (75-79 years of age).

Paediatric patients

During treatment with the recommended doses to children from the age of 1 year, similar plasma concentrations were obtained as compared to adults. In children younger than 6 months, clearance of Meprazol is low due to low capacity to metabolise Meprazol.

Absorption

Omeprazole and omeprazole magnesium are acid labile and are therefore administered orally as enteric-coated granules in capsules or tablets. Absorption of omeprazole is rapid, with peak plasma levels occurring approximately 1-2 hours after dose. Absorption of omeprazole takes place in the small intestine and is usually completed within 3-6 hours. Concomitant intake of food has no influence on the bioavailability. The systemic availability (bioavailability) from a single oral dose of omeprazole is approximately 40%. After repeated once-daily administration, the bioavailability increases to about 60%.

Distribution

The apparent volume of distribution in healthy subjects is approximately 0.3 l/kg body weight. Omeprazole is 97% plasma protein bound.

Biotransformation

Omeprazole is completely metabolised by the cytochrome P450 system (CYP). The major part of its metabolism is dependent on the polymorphically expressed CYP2C19, 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 sulfone. As a consequence of high affinity of omeprazole to CYP2C19, there is a potential for competitive inhibition and metabolic drug-drug interactions with other substrates for CYP2C19. However, due to low affinity to CYP3A4, omeprazole has no potential to inhibit the metabolism of other CYP3A4 substrates. In addition, omeprazole lacks an inhibitory effect on the main CYP enzymes.

Approximately 3% of the Caucasian population and 15-20% of Asian populations lack a functional CYP2C19 enzyme and are called poor metabolisers. In such individuals the metabolism of omeprazole is probably mainly catalysed by CYP3A4. After repeated once-daily administration of 20 mg omeprazole, the mean AUC was 5 to 10 times higher in poor metabolisers than in subjects having a functional CYP2C19 enzyme (extensive metabolisers). Mean peak plasma concentrations were also higher, by 3 to 5 times. These findings have no implications for the posology of omeprazole.

Elimination

The plasma elimination half-life of omeprazole is usually shorter than one hour both after single and repeated oral once-daily dosing. Omeprazole is completely eliminated from plasma between doses with no tendency for accumulation during once-daily administration. Almost 80% of an oral dose of omeprazole is excreted as metabolites in the urine, the remainder in the faeces, primarily originating from bile secretion.

Linearity/non-linearity

The AUC of omeprazole increases with repeated administration. This increase is dose-dependent and results in a non-linear dose-AUC relationship after repeated administration. This time- and dose-dependency is due to a decrease of first pass metabolism and systemic clearance probably caused by an inhibition of the CYP2C19 enzyme by omeprazole and/or its metabolites (e.g. the sulfone).

No metabolite has been found to have any effect on gastric acid secretion.

Special populations

Hepatic impairment

The metabolism of omeprazole in patients with liver dysfunction is impaired, resulting in an increased AUC. Omeprazole has not shown any tendency to accumulate with once daily dosing.

Renal impairment

The pharmacokinetics of omeprazole, including systemic bioavailability and elimination rate, are unchanged in patients with reduced renal function.

Elderly

The metabolism rate of omeprazole is somewhat reduced in elderly subjects (75-79 years of age).

Paediatric population

During treatment with the recommended doses to children from the age of 1 year, similar plasma concentrations were obtained as compared to adults. In children younger than 6 months, clearance of omeprazole is low due to low capacity to metabolise omeprazole.

Special warnings and precautions for use

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In the presence of any alarm symptom (e.g. significant unintentional weight loss, recurrent vomiting, dysphagia, haematemesis or melaena) and when gastric ulcer is suspected or present, malignancy should be excluded, as treatment may alleviate symptoms and delay diagnosis.

Co-administration of atazanavir with proton pump inhibitors is not recommended. If the combination of atazanavir with a proton pump inhibitor is judged unavoidable, close clinical monitoring (e.g. virus load) is recommended in combination with an increase in the dose of atazanavir to 400mg with 100mg of ritonavir; Meprazol 20mg should not be exceeded.

Meprazol as with all acid blocking medicines, may reduce the absorption of vitamin B12 (cyanocobalamin) due to hypo or achlorhydria. This should be considered in patients with reduced body stores or risk factors for reduced vitamin B12 absorption on long-term therapy.

Meprazol is a CYP2C19 inhibitor. When starting or ending treatment with Meprazol, the potential for interactions with drugs metabolized through CYP2C19 should be considered. An interaction is observed between clopidogrel and Meprazol. The clinical relevance of this interaction is uncertain. As a precaution, concomitant use of Meprazol and clopidogrel should be discouraged.

Hypomagnesaemia

Severe hypomagnesaemia has been reported in patients treated with PPIs like Meprazol for at least three months, and in most cases for a year. Serious manifestations of hypomagnesaemia such as fatigue, tetany, delirium, convulsions, dizziness and ventricular arrhythmia can occur but they may begin insidiously and be overlooked. In most affected patients, hypomagnesaemia improved after magnesium replacement and discontinuation of the PPI.

For patients expected to be on prolonged treatment or who take PPIs with digoxin or other medicines that may cause hypomagnesaemia (e.g. diuretics), healthcare professionals should consider measuring magnesium levels before starting PPI treatment and periodically during treatment;

Proton pump inhibitors, especially if used in high doses and over long durations (>1 year), may modestly increase the risk of hip, wrist and spine fracture, predominantly in the elderly or in presence of other recognised risk factors. Observational studies suggest that proton pump inhibitors may increase the overall risk of fractures by 10-40%. Some of this increase may be due to other risk factors. Patients at risk of osteoporosis should receive care according to current clinical guidelines and they should have an adequate intake of vitamin D and calcium.

Subacute cutaneous lupus erythematosus (SCLE)

Proton pump inhibitors are associated with very infrequent cases of SCLE. If lesions occur, especially in sun-exposed areas of the skin, and if accompanied by arthralgia, the patient should seek medical help promptly and the healthcare professional should consider stopping Meprazol. SCLE after previous treatment with a proton pump inhibitor may increase the risk of SCLE with other proton pump inhibitors.

Interference with laboratory tests

Increased Chromogranin A (CgA) level may interfere with investigations for neuroendocrine tumours. To avoid this interference, Meprazol treatment should be stopped for at least five days before CgA measurements. If CgA and gastrin levels have not returned to reference range after initial measurement, measurements should be repeated 14 days after cessation of proton pump inhibitor treatment.

Patients with rare hereditary problems of fructose intolerance, glucose-galactose malabsorption or sucrase-isomaltase insufficiency should not take this medicine.

Treatment with proton pump inhibitors may lead to slightly increased risk of gastrointestinal infections such as Salmonella and Campylobacter and in hospitalised patients possibly also Clostridium difficile.

As in all long-term treatments, especially when exceeding a treatment period of 1 year, patients should be kept under regular surveillance.

Paediatric population:

Some children with chronic illnesses may require long-term treatment although it is not recommended.

In the presence of any alarm symptom (e.g. significant unintentional weight loss, recurrent vomiting, dysphagia, haematemesis or melena) and when gastric ulcer is suspected or present, malignancy should be excluded, as treatment may alleviate symptoms and delay diagnosis.

Co-administration of atazanavir with proton pump inhibitors is not recommended. If the combination of atazanavir with a proton pump inhibitor is judged unavoidable, close clinical monitoring (e.g virus load) is recommended in combination with an increase in the dose of atazanavir to 400 mg with 100 mg of ritonavir; omeprazole 20 mg should not be exceeded.

Omeprazole, as all acid-blocking medicines, may reduce the absorption of vitamin B12 (cyanocobalamin) due to hypo- or achlorhydria. This should be considered in patients with reduced body stores or risk factors for reduced vitamin B12 absorption on long-term therapy.

Omeprazole is a CYP2C19 inhibitor. When starting or ending treatment with omeprazole, the potential for interactions with drugs metabolised through CYP2C19 should be considered. An interaction is observed between clopidogrel and omeprazole. The clinical relevance of this interaction is uncertain. As a precaution, concomitant use of omeprazole and clopidogrel should be discouraged.

Severe hypomagnesaemia has been reported in patients treated with proton pump inhibitors (PPIs) like omeprazole for at least three months, and in most cases for a year. Serious manifestations of hypomagnesaemia such as fatigue, tetany, delirium, convulsions, dizziness and ventricular arrhythmia can occur but they may begin insidiously and be overlooked. In most affected patients, hypomagnesaemia improved after magnesium replacement and discontinuation of the PPI.

For patients expected to be on prolonged treatment or who take PPIs with digoxin or drugs that may cause hypomagnesaemia (e.g. diuretics), healthcare professionals should consider measuring magnesium levels before starting PPI treatment and periodically during treatment.

Proton pump inhibitors, especially if used in high doses and over long durations (>1 year), may modestly increase the risk of hip, wrist and spine fracture, predominantly in the elderly or in presence of other recognised risk factors. Observational studies suggest that proton pump inhibitors may increase the overall risk of fracture by 10-40%. Some of this increase may be due to other risk factors. Patients at risk of osteoporosis should receive care according to current clinical guidelines and they should have an adequate intake of vitamin D and calcium.

Subacute cutaneous lupus erythematosus (SCLE)

Proton pump inhibitors are associated with very infrequent cases of SCLE. If lesions occur, especially in sun-exposed areas of the skin, and if accompanied by arthralgia, the patient should seek medical help promptly and the health care professional should consider stopping Meprazol. SCLE after previous treatment with a proton pump inhibitor may increase the risk of SCLE with other proton pump inhibitors.

Interference with laboratory tests

Increased Chromogranin A (CgA) level may interfere with investigations for neuroendocrine tumours. To avoid this interference, omeprazole treatment should be stopped for at least 5 days before CgA measurements. If CgA and gastrin levels have not returned to reference range after initial measurement, measurements should be repeated 14 days after cessation of proton pump inhibitor treatment.

Some children with chronic illnesses may require long-term treatment although it is not recommended.

Meprazol contains lactose. Patients with rare hereditary problems of galactose intolerance, the Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.

Treatment with proton pump inhibitors may lead to slightly increased risk of gastrointestinal infections such as Salmonella and Campylobacter and, in hospitalised patients, possibly also Clostridium difficile.

As in all long-term treatments, especially when exceeding a treatment period of 1 year, patients should be kept under regular surveillance.

Effects on ability to drive and use machines

Capsules; Enteric-coated capsules; Lyophilizate for the preparation of a solution for infusions; Pellets; Semi-finished pellets; Substance-pelletsGastro-resistant capsule, hard; Powder and solvent for solution for injection; Powder for solution for infusion

Meprazol has no or negligible influence on the ability to drive or use machines. Adverse drug reactions such as dizziness and visual disturbance may occur. If affected, patients should not drive or operate machinery.

Meprazol is not likely to affect the ability to drive or use machines. Adverse drug reactions such as dizziness and visual disturbances may occur. If affected, patients should not drive or operate machinery.

Special precautions for disposal and other handling

Capsules; Enteric-coated capsules; Lyophilizate for the preparation of a solution for infusions; Pellets; Semi-finished pellets; Substance-pelletsGastro-resistant capsule, hard; Powder and solvent for solution for injection; Powder for solution for infusion

No special requirements for disposal.

No special requirements.