Omeprazole

(Redirected from Inhipump)

Omeprazole, sold under the brand names Prilosec and Losec, among others, is a medication used in the treatment of gastroesophageal reflux disease (GERD), peptic ulcer disease, and Zollinger–Ellison syndrome.[1] It is also used to prevent upper gastrointestinal bleeding in people who are at high risk.[1] Omeprazole is a proton-pump inhibitor (PPI) and its effectiveness is similar to that of other PPIs.[9] It can be taken by mouth or by injection into a vein.[1][10] It is also available in the fixed-dose combination medication omeprazole/sodium bicarbonate as Zegerid[11][12] and as Konvomep.[13]

Omeprazole
Clinical data
Pronunciation/ˈmɛprəzl/
Trade namesLosec, Prilosec, others[1][2]
AHFS/Drugs.comMonograph
MedlinePlusa693050
License data
Pregnancy
category
Routes of
administration
By mouth, intravenous
Drug classProton-pump inhibitor
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability35–76%[6][7]
Protein binding95%
MetabolismLiver (CYP2C19, CYP3A4)
Elimination half-life1–1.2 hours
Excretion80% (urine)
20% (bile via feces)
Identifiers
  • 5-Methoxy-2-[(4-methoxy-3,5-dimethylpyridin-2-yl)methanesulfinyl]-1H-benzimidazole
CAS Number
PubChem CID
IUPHAR/BPS
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
PDB ligand
CompTox Dashboard (EPA)
ECHA InfoCard100.122.967 Edit this at Wikidata
Chemical and physical data
FormulaC17H19N3O3S
Molar mass345.42 g·mol−1
3D model (JSmol)
ChiralityRacemic mixture
Density1.4±0.1[8] g/cm3
Melting point156 °C (313 °F)
  • CC1=CN=C(C(=C1OC)C)CS(=O)C2=NC3=C(N2)C=C(C=C3)OC
  • InChI=1S/C17H19N3O3S/c1-10-8-18-15(11(2)16(10)23-4)9-24(21)17-19-13-6-5-12(22-3)7-14(13)20-17/h5-8H,9H2,1-4H3,(H,19,20) checkY
  • Key:SUBDBMMJDZJVOS-UHFFFAOYSA-N checkY
  (verify)

Common side effects include nausea, vomiting, headaches, abdominal pain, and increased intestinal gas.[1][14] Serious side effects may include Clostridioides difficile colitis, an increased risk of pneumonia, an increased risk of bone fractures, and the potential of masking stomach cancer.[1] Whether it is safe for use in pregnancy is unclear.[1] It works by blocking the release of stomach acid.[1]

Omeprazole was patented in 1978 and approved for medical use in 1988.[15][16] It is on the World Health Organization's List of Essential Medicines.[17] It is available as a generic medication.[1] In 2022, it was the ninth most commonly prescribed medication in the United States, with more than 52 million prescriptions.[18][19] It is also available without a prescription in the United States.[20][21]

Medical uses

edit

Omeprazole can be used in the treatment of gastroesophageal reflux disease (GERD), peptic ulcers, erosive esophagitis, Zollinger–Ellison syndrome, and eosinophilic esophagitis.[22][1]

Peptic ulcers

edit

Peptic ulcers may be treated with omeprazole. Infection with Helicobacter pylori can be treated by taking omeprazole, amoxicillin, and clarithromycin together for 7–14 days.[23] Amoxicillin may be replaced with metronidazole in patients who are allergic to penicillin.[24]

Adverse effects

edit

Adverse effects occurring in at least 1% of people include:[25][failed verification]

  • Central nervous system: headache (7%), dizziness (2%)
  • Respiratory: upper respiratory tract infection (2%), cough (1%)
  • Gastrointestinal: abdominal pain (5%), diarrhea (4%), nausea (4%), vomiting (3%), flatulence (3%), acid regurgitation (2%), constipation (2%)
  • Neuromuscular and skeletal: back pain (1%), weakness (1%)
  • Dermatologic: rash (2%)

Other concerns related to adverse effects are:

Concern has been expressed regarding vitamin B12[30] and iron malabsorption,[31] but effects seem to be insignificant, especially when supplement therapy is provided.[32]

Since their introduction, proton-pump inhibitors (PPIs, especially omeprazole) have also been associated with several cases of acute interstitial nephritis,[33] an inflammation of the kidneys that often occurs as an adverse drug reaction.

Long-term use

edit

Long-term use of PPIs is strongly associated with the development of benign polyps from fundic glands (which is distinct from fundic gland polyposis); these polyps do not cause cancer and resolve when PPIs are discontinued. No association is seen between PPI use and cancer, but use of PPIs may mask gastric cancers or other serious gastric problems and physicians should be aware of this effect.[34]

There is a possible association between long term use and dementia which requires further study to confirm.[35]

A review article in U.S. Pharmacist in 2013 states that long-term use of PPIs is associated with decreased calcium absorption (causing increased risk of osteoporosis and fractures), decreased magnesium absorption (causing electrolyte disturbances), and increased risk of certain infections such as C. difficile and community-acquired pneumonia. They hypothesize that this is due to decreased stomach acid production.[36]

Pregnancy and breastfeeding

edit

The safety of using omeprazole has not been established in pregnant or breastfeeding women.[14] Epidemiological data do not show an increased risk of major birth defects after maternal use of omeprazole during pregnancy.[37]

Interactions

edit
 
Omeprazol Actavis 20 mg, bottle and pills in Sweden

Important drug interactions are rare.[38][39] However, the most significant major drug interaction concern is the decreased activation of clopidogrel when taken together with omeprazole.[40] Although still controversial,[41] this may increase the risk of stroke or heart attack in people taking clopidogrel to prevent these events.

This interaction is possible because omeprazole is an inhibitor of the enzymes CYP2C19 and CYP3A4.[42] Clopidogrel is an inactive prodrug that partially depends on CYP2C19 for conversion to its active form. Inhibition of CYP2C19 may block the activation of clopidogrel, which could reduce its effects.[43][44]

Almost all benzodiazepines are metabolised by the CYP3A4 and CYP2D6 pathways, and inhibition of these enzymes results in a higher area under the curve (i.e., the total effect over time of a given dose). Other examples of drugs dependent on CYP3A4 for their metabolism are escitalopram,[45] warfarin,[46] oxycodone, tramadol, and oxymorphone. The concentrations of these drugs may increase if they are used concomitantly with omeprazole.[47]

Omeprazole is also a competitive inhibitor of p-glycoprotein, as are other PPIs.[48]

Drugs that depend on an acidic stomach environment (such as ketoconazole or atazanavir) may be poorly absorbed, whereas acid-labile antibiotics (such as erythromycin which is a very strong CYP3A4 inhibitor) may be absorbed to a greater extent than normal due to the more alkaline environment of the stomach.[47]

St. John's wort (Hypericum perforatum) and Ginkgo biloba significantly reduce plasma concentrations of omeprazole through induction of CYP3A4 and CYP2C19.[49]

Proton-pump inhibitors like omeprazole have been found to increase the plasma concentrations of methotrexate.[50]

Pharmacology

edit

Omeprazole irreversibly blocks the enzyme system on parietal cells that is needed for the secretion of gastric acid. It is a specific H+/K+ATPase inhibitor. This is the enzyme needed for the final step in the secretion of gastric acid.[51]

Mechanism of action

edit

Omeprazole is a selective and irreversible proton pump inhibitor. It suppresses stomach acid secretion by specific inhibition of the H+/K+-ATPase system found at the secretory surface of gastric parietal cells. Because this enzyme system is regarded as the acid (proton, or H+) pump within the gastric mucosa, omeprazole inhibits the final step of acid production.[51]

Omeprazole also inhibits both basal and stimulated acid secretion irrespective of the stimulus[52] as it blocks the last step in acid secretion.[52] The drug binds non-competitively so it has a dose-dependent effect.[53]

The inhibitory effect of omeprazole occurs within 1 hour after oral administration. The maximum effect occurs within 2 hours. The duration of inhibition is up to 72 hours. When omeprazole is stopped, baseline stomach acid secretory activity returns after 3 to 5 days. The inhibitory effect of omeprazole on acid secretion will plateau after 4 days of repeated daily dosing.[54]

Pharmacokinetics

edit

The absorption of omeprazole takes place in the small intestine and is usually completed within 3 to 6 hours. The systemic bioavailability of omeprazole after repeated doses is about 60%.[55] Omeprazole has a volume of distribution of 0.4 L/kg. It has high plasma protein binding of 95%.[53]

Omeprazole, as well as other PPIs, are only effective on active H+/K+-ATPase pumps. These pumps are stimulated in the presence of food to aid in digestion. For this reason, patients should be advised to take omeprazole with a glass of water, before a meal.[56] Additionally, most sources recommend that after taking omeprazole, at least 30 minutes should be allowed to elapse before eating[57][58] (at least 60 minutes for immediate-release omeprazole plus sodium bicarbonate products, such as Zegerid).[12]

Omeprazole is completely metabolized by the cytochrome P450 system, mainly in the liver, by CYP2C19 and CYP3A4 isoenzymes.[14] Identified metabolites are the sulfone, the sulfide, and hydroxy-omeprazole, which exert no significant effect on acid secretion. About 77% of an orally given dose is excreted as metabolites in the urine, and the remainder is found in the feces, primarily originating from bile secretion.[52] Omeprazole has a half life of 0.5 to 1 hour.[52]

Chemistry

edit

Omeprazole contains a tricoordinated sulfinyl sulfur in a pyramidal structure and therefore can exist as either the (S)- or (R)-enantiomers. Omeprazole is a racemate, an equal mixture of the two. In the acidic conditions of the canaliculi of parietal cells, both enantiomers are converted to achiral products (sulfenic acid and sulfenamide configurations) which react with a cysteine group in H+/K+ ATPase, thereby inhibiting the ability of the parietal cells to produce gastric acid.[citation needed]

 

AstraZeneca also developed esomeprazole (Nexium) which is a eutomer, purely the (S)-enantiomer, rather than a racemate like omeprazole.[medical citation needed]

Omeprazole undergoes a chiral shift in vivo which converts the inactive (R)-enantiomer to the active (S)-enantiomer, doubling the concentration of the active form.[59] This chiral shift is accomplished by the CYP2C19 isozyme of cytochrome P450, which is not found equally in all human populations. Those who do not metabolize the drug effectively are called "poor metabolizers". The proportion of the poor metabolizer phenotype varies widely between populations, from 2.0 to 2.5% in African Americans and white Americans to >20% in Asians. Several pharmacogenomics studies have suggested that PPI treatment should be tailored according to CYP2C19 metabolism status.[60]

Measurement in body fluids

edit

Omeprazole may be quantified in plasma or serum to monitor therapy or to confirm a diagnosis of poisoning in hospitalized patients. Plasma omeprazole concentrations are usually in a range of 0.2–1.2 mg/L in persons receiving the drug therapeutically by the oral route and 1–6 mg/L in people with acute overdose. Enantiomeric chromatographic methods are available to distinguish esomeprazole from racemic omeprazole.[61]

History

edit

Omeprazole was first made in 1979 by Swedish AB Hässle, part of Astra AB. It was the first of the proton pump inhibitors (PPI).[62][63] Astra AB, now AstraZeneca, launched it as an ulcer medicine under the name Losec in Sweden. It was first sold in the United States in 1989 under the brand name Losec. In 1990, at the request of the U.S. Food and Drug Administration, the brand name Losec was changed to Prilosec to avoid confusion with the diuretic Lasix (furosemide).[64] The new name led to confusion between omeprazole (Prilosec) and fluoxetine (Prozac), an antidepressant.[64]

Society and culture

edit

Economics

edit

When Prilosec's U.S. patent expired in April 2001, AstraZeneca introduced esomeprazole (Nexium) as a patented replacement drug.[65] Many companies introduced generics as AstraZeneca's patents expired worldwide, which are available under many brand names.

Omeprazole was a subject of a patent litigation in the U.S.[66] The invention involved application of two different coatings to a drug in pill form to ensure that the omeprazole did not disintegrate before reaching its intended site of action in stomach. Although the solution by means of two coating was obvious, the patent was found valid, because the source of the problem was non-obvious and was discovered by the patentee.[67]

In September 2023, AstraZeneca announced it would pay $425 million to settle product liability litigations against Prilosec in the United States.[68]

Brand names

edit

Brand names include Losec, Prilosec, Zegerid, Miracid, and Omez.[2][1]

References

edit
  1. ^ a b c d e f g h i j k "Omeprazole". The American Society of Health-System Pharmacists. Archived from the original on 19 February 2011. Retrieved 21 October 2018.
  2. ^ a b "Omeprazole international". Drugs.com. 3 February 2020. Archived from the original on 28 February 2020. Retrieved 27 February 2020.
  3. ^ "Omeprazole Use During Pregnancy". Drugs.com. 11 April 2019. Archived from the original on 15 February 2020. Retrieved 15 February 2020.
  4. ^ "FDA-sourced list of all drugs with black box warnings (Use Download Full Results and View Query links.)". nctr-crs.fda.gov. FDA. Retrieved 22 October 2023.
  5. ^ "Product monograph brand safety updates". Health Canada. 7 July 2016. Retrieved 1 April 2024.
  6. ^ "Prilosec- omeprazole magnesium capsule, delayed release Prilosec- omeprazole magnesium granule, delayed release". DailyMed. 22 December 2016. Archived from the original on 27 December 2019. Retrieved 15 February 2020.
  7. ^ Vaz-da-Silva M, Loureiro AI, Nunes T, Maia J, Tavares S, Falcão A, et al. (2005). "Bioavailability and bioequivalence of two enteric-coated formulations of omeprazole in fasting and fed conditions". Clinical Drug Investigation. 25 (6): 391–399. doi:10.2165/00044011-200525060-00004. PMID 17532679. S2CID 22082780. Archived from the original on 13 March 2013. Retrieved 21 October 2018.
  8. ^ "Omeprazole MSDS". Archived from the original on 19 April 2017. Retrieved 21 October 2018.
  9. ^ "[99] Comparative effectiveness of proton pump inhibitors | Therapeutics Initiative". 28 June 2016. Archived from the original on 30 October 2020. Retrieved 14 July 2016.
  10. ^ "Omeprazole 40 mg Powder for Solution for Infusion". EMC. 10 February 2016. Archived from the original on 7 April 2016. Retrieved 21 October 2018.
  11. ^ "Zegerid- omeprazole and sodium bicarbonate powder, for suspension Zegerid- omeprazole and sodium bicarbonate capsule". DailyMed. 4 March 2022. Retrieved 16 December 2022.
  12. ^ a b "Zegerid OTC- omeprazole and sodium bicarbonate capsule, gelatin coated". DailyMed. 5 December 2022. Retrieved 16 December 2022.
  13. ^ "Konvomep- omeprazole and sodium bicarbonate kit". DailyMed. 30 August 2022. Retrieved 21 January 2023.
  14. ^ a b c Vallerand AH, Sanoski CA, Deglin JH (2015). Davis's Drug Guide for Nurses (14th ed.). F.A. Davis Company. pp. 924–925. ISBN 978-0-8036-4085-6. OCLC 881473728.
  15. ^ "Drug Approval Package: Prilosec (Omeprazole) NDA# 019-810s38s50s5". U.S. Food and Drug Administration (FDA). 30 March 2001. Archived from the original on 1 April 2021. Retrieved 5 October 2022.
  16. ^ Fischer J, Ganellin CR (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 445. ISBN 9783527607495. Archived from the original on 3 August 2020. Retrieved 29 June 2020.
  17. ^ World Health Organization (2023). The selection and use of essential medicines 2023: web annex A: World Health Organization model list of essential medicines: 23rd list (2023). Geneva: World Health Organization. hdl:10665/371090. WHO/MHP/HPS/EML/2023.02.
  18. ^ "The Top 300 of 2022". ClinCalc. Archived from the original on 30 August 2024. Retrieved 30 August 2024.
  19. ^ "Omeprazole Drug Usage Statistics, United States, 2013 - 2022". ClinCalc. Retrieved 30 August 2024.
  20. ^ "Questions and Answers on Prilosec OTC (omeprazole)". U.S. Food and Drug Administration (FDA). 3 November 2018. Archived from the original on 28 August 2021. Retrieved 2 March 2020.
  21. ^ "Drug Approval Package: Prilosec (Omeprazole Magnesium) NDA #021229". U.S. Food and Drug Administration (FDA). Archived from the original on 24 January 2022. Retrieved 6 October 2022.
  22. ^ Cheng E (July 2013). "Proton pump inhibitors for eosinophilic oesophagitis". Current Opinion in Gastroenterology. 29 (4): 416–420. doi:10.1097/MOG.0b013e32835fb50e. PMC 4118554. PMID 23449027.
  23. ^ Fuccio L, Minardi ME, Zagari RM, Grilli D, Magrini N, Bazzoli F (October 2007). "Meta-analysis: duration of first-line proton-pump inhibitor based triple therapy for Helicobacter pylori eradication". Annals of Internal Medicine. 147 (8): 553–562. doi:10.7326/0003-4819-147-8-200710160-00008. PMID 17938394. S2CID 11644009.
  24. ^ Malfertheiner P, Megraud F, O'Morain C, Bazzoli F, El-Omar E, Graham D, et al. (June 2007). "Current concepts in the management of Helicobacter pylori infection: the Maastricht III Consensus Report". Gut. 56 (6): 772–781. doi:10.1136/gut.2006.101634. PMC 1954853. PMID 17170018.
  25. ^ McTavish D, Buckley MM, Heel RC (July 1991). "Omeprazole. An updated review of its pharmacology and therapeutic use in acid-related disorders". Drugs. 42 (1): 138–170. doi:10.2165/00003495-199142010-00008. PMID 1718683.
  26. ^ Abou Chakra CN, Pepin J, Sirard S, Valiquette L (21 June 2014). "Risk factors for recurrence, complications and mortality in Clostridium difficile infection: a systematic review". PLOS ONE. 9 (6): e98400. Bibcode:2014PLoSO...998400A. doi:10.1371/journal.pone.0098400. PMC 4045753. PMID 24897375.
  27. ^ Yang YX, Lewis JD, Epstein S, Metz DC (December 2006). "Long-term proton pump inhibitor therapy and risk of hip fracture". JAMA. 296 (24): 2947–2953. doi:10.1001/jama.296.24.2947. PMID 17190895.
  28. ^ Yu EW, Bauer SR, Bain PA, Bauer DC (June 2011). "Proton pump inhibitors and risk of fractures: a meta-analysis of 11 international studies". The American Journal of Medicine. 124 (6): 519–526. doi:10.1016/j.amjmed.2011.01.007. PMC 3101476. PMID 21605729.
  29. ^ Hess MW, Hoenderop JG, Bindels RJ, Drenth JP (September 2012). "Systematic review: hypomagnesaemia induced by proton pump inhibition". Alimentary Pharmacology & Therapeutics. 36 (5): 405–413. doi:10.1111/j.1365-2036.2012.05201.x. PMID 22762246. S2CID 9073390.
  30. ^ Neal K, Logan R (July 2001). "Potential gastrointestinal effects of long-term acid suppression with proton pump inhibitors". Alimentary Pharmacology & Therapeutics. 15 (7): 1085–1086. doi:10.1046/j.1365-2036.2001.0994a.x. PMID 11421886. S2CID 39455836.
  31. ^ Sarzynski E, Puttarajappa C, Xie Y, Grover M, Laird-Fick H (August 2011). "Association between proton pump inhibitor use and anemia: a retrospective cohort study". Digestive Diseases and Sciences. 56 (8): 2349–2353. doi:10.1007/s10620-011-1589-y. PMID 21318590. S2CID 33574008.
  32. ^ McColl KE (March 2009). "Effect of proton pump inhibitors on vitamins and iron". The American Journal of Gastroenterology. 104 (Suppl 2): S5–S9. doi:10.1038/ajg.2009.45. PMID 19262546. S2CID 31455416.
  33. ^ Härmark L, van der Wiel HE, de Groot MC, van Grootheest AC (December 2007). "Proton pump inhibitor-induced acute interstitial nephritis". British Journal of Clinical Pharmacology. 64 (6): 819–823. doi:10.1111/j.1365-2125.2007.02927.x. PMC 2198775. PMID 17635502.
  34. ^ Corleto VD, Festa S, Di Giulio E, Annibale B (February 2014). "Proton pump inhibitor therapy and potential long-term harm". Current Opinion in Endocrinology, Diabetes, and Obesity. 21 (1): 3–8. doi:10.1097/med.0000000000000031. hdl:11573/618643. PMID 24310148. S2CID 205791135.
  35. ^ Eusebi LH, Rabitti S, Artesiani ML, Gelli D, Montagnani M, Zagari RM, et al. (July 2017). "Proton pump inhibitors: Risks of long-term use". Journal of Gastroenterology and Hepatology. 32 (7): 1295–1302. doi:10.1111/jgh.13737. PMID 28092694.
  36. ^ O'Neill LW, Culpepper BL, Galdo JA (2013). "Long-Term Consequences of Chronic Proton Pump Inhibitor Use". US Pharmacist. 38 (12): 38–42. Archived from the original on 21 January 2021. Retrieved 28 December 2020.
  37. ^ Pasternak B, Hviid A (November 2010). "Use of proton-pump inhibitors in early pregnancy and the risk of birth defects". The New England Journal of Medicine. 363 (22): 2114–2123. doi:10.1056/NEJMoa1002689. PMID 21105793. S2CID 10954538.
  38. ^ Fitzakerley J. "2014 Treatments for Acid-Peptic Diseases". University of Minnesota Medical School Duluth. Archived from the original on 19 April 2014. Retrieved 21 October 2018.
  39. ^ "Proton Pump Inhibitor: Use in Adults" (PDF). CMS Medicaid Integrity Program. Archived from the original (PDF) on 12 December 2013. Retrieved 21 October 2018.
  40. ^ Douglas IJ, Evans SJ, Hingorani AD, Grosso AM, Timmis A, Hemingway H, et al. (July 2012). "Clopidogrel and interaction with proton pump inhibitors: comparison between cohort and within person study designs". BMJ. 345: e4388. doi:10.1136/bmj.e4388. PMC 3392956. PMID 22782731.
  41. ^ Focks JJ, Brouwer MA, van Oijen MG, Lanas A, Bhatt DL, Verheugt FW (April 2013). "Concomitant use of clopidogrel and proton pump inhibitors: impact on platelet function and clinical outcome- a systematic review". Heart. 99 (8): 520–527. doi:10.1136/heartjnl-2012-302371. PMID 22851683. S2CID 23689175.
  42. ^ Shirasaka Y, Sager JE, Lutz JD, Davis C, Isoherranen N (July 2013). "Inhibition of CYP2C19 and CYP3A4 by omeprazole metabolites and their contribution to drug-drug interactions". Drug Metabolism and Disposition. 41 (7): 1414–1424. doi:10.1124/dmd.113.051722. PMC 3684819. PMID 23620487.
  43. ^ Lau WC, Gurbel PA (March 2009). "The drug-drug interaction between proton pump inhibitors and clopidogrel". CMAJ. 180 (7): 699–700. doi:10.1503/cmaj.090251. PMC 2659824. PMID 19332744.
  44. ^ Norgard NB, Mathews KD, Wall GC (July 2009). "Drug-drug interaction between clopidogrel and the proton pump inhibitors". The Annals of Pharmacotherapy. 43 (7): 1266–1274. doi:10.1345/aph.1M051. PMID 19470853. S2CID 13227312.
  45. ^ Selective Serotonin Reuptake Inhibitors and CYP2D6 at eMedicine
  46. ^ Daly AK, King BP (May 2003). "Pharmacogenetics of oral anticoagulants". Pharmacogenetics. 13 (5): 247–252. doi:10.1097/00008571-200305000-00002. PMID 12724615.
  47. ^ a b Stedman CA, Barclay ML (August 2000). "Review article: comparison of the pharmacokinetics, acid suppression and efficacy of proton pump inhibitors". Alimentary Pharmacology & Therapeutics. 14 (8): 963–978. doi:10.1046/j.1365-2036.2000.00788.x. PMID 10930890. S2CID 45337685.
  48. ^ Pauli-Magnus C, Rekersbrink S, Klotz U, Fromm MF (December 2001). "Interaction of omeprazole, lansoprazole and pantoprazole with P-glycoprotein". Naunyn-Schmiedeberg's Archives of Pharmacology. 364 (6): 551–557. doi:10.1007/s00210-001-0489-7. PMID 11770010. S2CID 19990184.
  49. ^ Izzo AA, Ernst E (2009). "Interactions between herbal medicines and prescribed drugs: an updated systematic review". Drugs. 69 (13): 1777–1798. doi:10.2165/11317010-000000000-00000. PMID 19719333. S2CID 25720882.
  50. ^ Brayfield A, ed. (6 January 2014). "Methotrexate". Martindale: The Complete Drug Reference. Pharmaceutical Press. Archived from the original on 28 August 2021. Retrieved 12 April 2014.
  51. ^ a b Howden CW (January 1991). "Clinical pharmacology of omeprazole". Clinical Pharmacokinetics. 20 (1): 38–49. doi:10.2165/00003088-199120010-00003. PMID 2029801. S2CID 25855436.
  52. ^ a b c d "Omeprazole". www.drugbank.ca. Archived from the original on 30 January 2019. Retrieved 29 January 2019.
  53. ^ a b Clissold SP, Campoli-Richards DM (July 1986). "Omeprazole. A preliminary review of its pharmacodynamic and pharmacokinetic properties, and therapeutic potential in peptic ulcer disease and Zollinger-Ellison syndrome". Drugs. 32 (1): 15–47. doi:10.2165/00003495-198632010-00002. PMID 3527658.
  54. ^ "Omeprazole package insert". India: Dr. Reddy's Laboratories Limited. June 2013. Archived from the original on 19 April 2014.
  55. ^ Cederberg C, Andersson T, Skånberg I (1 January 1989). "Omeprazole: pharmacokinetics and metabolism in man". Scandinavian Journal of Gastroenterology. Supplement. 166 (sup166): 33–40. doi:10.3109/00365528909091241. PMID 2690330.
  56. ^ Katz PO, Gerson LB, Vela MF (March 2013). "Guidelines for the diagnosis and management of gastroesophageal reflux disease". The American Journal of Gastroenterology. 108 (3): 308–28, quiz 329. doi:10.1038/ajg.2012.444. PMID 23419381. S2CID 8198975.
  57. ^ "Omeprazole, in The Free Medical Dictionary". Archived from the original on 12 June 2011. Retrieved 11 November 2010.
  58. ^ "Omeprazole". Drugs.com. Archived from the original on 19 February 2011. Retrieved 11 November 2010.
  59. ^ "Nexium Prescribing Information" (PDF). AstraZeneca Pharmaceuticals. Archived from the original (PDF) on 8 October 2009.
  60. ^ Furuta T, Shirai N, Sugimoto M, Nakamura A, Hishida A, Ishizaki T (June 2005). "Influence of CYP2C19 pharmacogenetic polymorphism on proton pump inhibitor-based therapies". Drug Metabolism and Pharmacokinetics. 20 (3): 153–167. doi:10.2133/dmpk.20.153. PMID 15988117. S2CID 19090952.
  61. ^ Baselt RC, Disposition of Toxic Drugs and Chemicals in Man, 8th edition, Biomedical Publications, Foster City, CA, 2008, pp. 1146–7. ISBN 978-0-9626523-7-0.
  62. ^ "Trends in Drug Patenting - Case Studies: THE CASES: 5. OMEPRAZOLE". apps.who.int. Archived from the original on 2 October 2010. Retrieved 22 August 2019.
  63. ^ Fellenius E, Berglindh T, Sachs G, Olbe L, Elander B, Sjöstrand SE, et al. (March 1981). "Substituted benzimidazoles inhibit gastric acid secretion by blocking (H+ + K+)ATPase". Nature. 290 (5802): 159–161. Bibcode:1981Natur.290..159F. doi:10.1038/290159a0. PMID 6259537. S2CID 4368190.
  64. ^ a b Farley D (July–August 1995). "Making it easier to read prescriptions". FDA Consumer. 29 (6): 25–27. PMID 10143448. Archived from the original on 15 March 2012. Retrieved 26 January 2011.
  65. ^ Harris G (6 June 2002). "Prilosec's Maker Switches Users To Nexium, Thwarting Generics". The Wall Street Journal. Archived from the original on 6 August 2017.
  66. ^ "AstraZeneca awarded damages in Prilosec patent litigation". AstraZeneca (Press release). 3 December 2013. Retrieved 4 October 2023.
  67. ^ "IN RE OMEPRAZOLE PATENT LITIGATION, Court of Appeals, Federal Circuit 2011 - Google Scholar".
  68. ^ "AstraZeneca to pay $425 mln to settle Nexium, Prilosec litigation in US". Reuters. 3 October 2023. Retrieved 3 October 2023.

Further reading

edit
edit