Sử dụng PPI ức bơm proton
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Sử dụng PPI ức bơm proton
- 1. CẬP NHẬT SỬ DỤNG PPI TRONG THỰC HÀNH Y HỌC GIA ĐÌNH TS.BS CK2. Trần Thị Khánh Tường ĐHYK Phạm Ngọc Thạch
- 2. NỘI DUNGNỘI DUNG 1. Nhắc lại • Cơ chế tiết acid • Cơ chế hoạt động của PPI • Dược lực học của PPI • Chuyển hóa PPI 1. Vai trò của PPI trong điều trị 2. Tương tác thuốc 3. Tính an toàn và vấn đề ngưng sử dụng PPI
- 3. NHẮC LẠI
- 4. TẾ BÀO THÀNH Tb thành và bơm proton không hoạt động trước ăn và trong bữa ăn CƠ CHẾ TIẾT ACID (tt)
- 5. PPI CƠ CHẾ TIẾT ACID (tt)
- 6. Proton hóa trong môi trường acid Chuyển thành sulphenamide Phản ứng với SH của gốc cysteines của H+ ,K+ - ATPase Ức chế H+ ,K+ - ATPase Ức chế PPI ( Protonation ) Sulphenamide K+ H+ ,K+ - ATPase (Proton Pump) Tiểu quản bài tiết H+ Ức chế tiết acid mạnh nhất* PPIs là tiền chất (pro-drug) hoạt hóa trong môi trường acid ức chế bơm proton Hoạt hóa tùy thuộc: pH ở tiểu quản bài tiết pKa của PPI CƠ CHẾ HOẠT ĐỘNG CỦA PPI * Wolfe MM, Sachs G. Gastroenterology. 2002;118(2 Suppl 1):S9
- 7. • PPI được hoạt hóa trong môi trường acid hoạt hoá kém khi dùng cùng lúc với các thuốc kháng tiết khác (antacide, H2RAs, anticholinergic agents, misoprostol, hay somatostatin) Không nên uống PPI cùng lúc với các thuốc kháng tiết khác
- 8. • PPIs: hiệu quả nhất khi uống trước ăn 30 đến 60 phút vào máu vài giờ sau ăn lúc tế bào thành được kích thích và bơm proton hoạt động • Bơm proton được huy động nhiều nhất trong tế bào thành sau thời gian nhịn đói kéo dài nên uống PPI trước bữa ăn đầu tiên trong ngày. • Nếu phải uống 2 lần/ ngày uống 30-60 phút trước ăn sáng và 30-60 phút trước ăn tối PPI nên uống 30-60 phút trước ăn sáng để ức chế acid tối đa
- 9. CƠ CHẾ HOẠT ĐỘNG CỦA PPI (tt) pKa: là pH mà PPI có 50% ở dạng hoạt hóa Tốc độ hoạt hóa tùy thuộc vào pKa : Rabe >Ome/ Esome = Lanso/dexlanzo > Panto * * Shin JM, Cho YM, Sachs G. Chemistry of covalent inhibition of the gastric (H+, K+)-ATPase by proton pump inhibitors. J Am Chem Soc 2004; 126:7800.
- 12. DƯỢC LỰC HỌC
- 13. CHUYỂN HÓA THUỐC
- 14. CYP2C19*2 in exon 5 ← 119bp ← 93bp ← 169b p ← 120b p 1M 2 3 4 5 6 CYP2C19*3 in exon 4 Homozygous extensive metabolizer = Extensive metabolizer (EM) Heterozygous extensive metabolizer - = Intermediate metabolizer (IM) Poor metabolizer (PM) *1/*1 *1/*2 *1/*3 *2/*3 *2/*2 *3/*3 PCR-RFLP patterns for CYP2C19 genotyping. CYP2C19 genotyping pattern are determined by the combination of cleavage patterns for CYP2C19*2 and CYP2C19*3. KIỂU GEN VÀ KIỂU HÌNH CYP2C19
- 15. PHÂN BỐ KIỂU HÌNH CỦA CYP2C19 n EM IM PM Trung Quốc 121 26,4% 49,6% 24% Nhật Bản 96 36,5% 45,8% 17,7% Thái Lan 121 37,2% 47,1% 15,7% Việt Nam 90 40% 40% 20% Da trắng 1.356 72,6% 25,3% 2,1% Yamada S. J Gastroenterol. 2001, 36: 669-672 Hong-Guang Xie et al. Pharmacogenetics 1999; 9: 539-549
- 16. PPI có CH càng nhanh clearance càng tăng nồng độ thuốc càng giảm nhanh giảm hiệu quả kháng tiết * PM: có tốc độ CH chậm hiệu quả mạnh EM: có tốc độ CH nhanh hiệu quả kém có thể gây thất bại diệt trừ H. Pylori, loét/ GERD kháng trị PPI nào có CH ít phụ thuộc vào CYP2C9 có : Hiệu quả ĐT ổn định, ít bị ảnh hưởng bởi kiểu hình CYP2C19 Ít tương tác thuốc KIỂU HÌNH CYP2C19 VÀ HIỆU QUẢ ĐT CỦA PPI * Krisztina Hagymási; Pharmacogenomics. 2011;12(6):873-888.
- 17. KIỂU HÌNH CYP2C19 ẢNH HƯỞNG LÊN pH DẠ DÀY
- 18. CHUYỂN HOÁ ESOMEPRAZOLE Andersson T, et al. Aliment Pharmacol. Ther. 15(10), 1563–1569 (2001). Krisztina Hagymási; Pharmacogenomics. 2011;12(6):873-888.
- 19. VAI TRÒ CỦA PPI TRONG ĐIỀU TRỊ
- 20. CÁC LOẠI PPI Loại uống Thế hệ 1 Pantoprazole 40 mg Lansoprazole 15, 30 mg / Dexlansoprazole Omeprazole 20 mg Thế hệ 2 Esomeprazole 20, 40 mg Rabeprazole 10, 20 mg Loại chích Omeprazole 40mg (chỉ có một số nước) Pantoprazole 40mg Esomeprazole 40mg
- 21. CHỈ ĐỊNH DÙNG PPI Điều trị loét và các biến chứng Dự phòng tái XH trong XHTH ko do vỡ giãn TMTQ Điều trị và ngừa loét do NSAID Tiệt trừ H.Pylori Điều trị GERD và các biến chứng Điều trị HC Zollinger-Ellison Khó tiêu chức năng (đặc biệt HC đau TV)
- 22. Management of Patients With Ulcer Bleeding 20. After successful endoscopic hemostasis, intravenous PPI therapy with 80 mg bolus followed by 8 mg/h continuous infusion for 72 h should be given to patients who have an ulcer with active bleeding, a non-bleeding visible vessel, or an adherent clot (Strong recommendation). 21. Patients with ulcers that have flat pigmented spots or clean bases can receive standard PPI therapy (e.g., oral PPI once daily) (Strong recommendation). © 2012 by the American College of Gastroenterology
- 23. Guidelines for Prevention of NSAID-Related Ulcer Complications Am J Gastroenterol 2009; 104:728 – 738
- 24. PPI VÀ DIỆT TRỪ H.Pylori Tác động trực tiếp lên H.Pylori (ức chế sx urease) Cải thiện hoạt tính KS Cải thiện quá trình giao thuốc đến vị trí Maastricht IV guideline (2012): PPI hiện diện trong tất cả các phác đồ diệt trừ Hpylori
- 25. LIỀU PPIs TRONG DIỆT TRỪ H pylori
- 26. Maastricht IV guideline (2012)
- 27. Maastricht IV guideline (2012)
- 32. TORONTO 2016 - KHÁNG CLA CAO
- 34. GERD
- 35. 4. An 8-week course of PPIs is the therapy of choice for symptom relief and healing of erosive esophagitis (Strong recommendation, high level of evidence). 6. PPI therapy should be initiated at once a day dosing, before the first meal of the day. (Strong recommendation, moderate level of evidence). For patients with partial response to once daily therapy, tailored therapy with adjustment of dose timing and / or twice daily dosing should be considered in patients with night-time symptoms, variable schedules, and / or sleep disturbance. (Strong recommendation, low level of evidence). Am J Gastroenterol 2013; 108:308–328 Management of Patients With GERD
- 36. 10. H2RA therapy can be used as a maintenance option in patients without erosive disease if patients experience heartburn relief. (Conditional recommendation, moderate level of evidence). Bedtime H2RA therapy can be added to daytime PPI therapy in selected patients with objective evidence of night- time reflux if needed, but may be associated with the development of tachyphlaxis after several weeks of use. (Conditional recommendation, low level of evidence) Maintenance PPI therapy should be administered for GERD patients who continue to have symptoms after PPI is discontinued, and in patients with complications including erosive esophagitis and Barrett’s esophagus. (Strong recommendation, moderate level of evidence). For patients who require long-term PPI therapy, it should be administered in the lowest effective dose, including on demand or intermittent therapy. (Conditional recommendation, low level of evidence) Am J Gastroenterol 2013; 108:308–328 Management of Patients With GERD
- 37. KHÓ TIÊU CHỨC NĂNG PPIs • Liệu pháp điều trị chính, hiệu quả hơn ở nhóm HC đau TV (EPS) • Meta analysis: giảm triệu chứng với NNT=15, RRR 10,3% * H2 receptor antagonists • Meta analysis: NNT=7, RRR 23% **, hầu hết NC thiết kế kém và xếp nhầm GERD vào khó tiêu chức năng.
- 38. Camilleri, M. Stanghellini, V. Nat. Rev. Gastroenterol. Hepatol. 2013 Jun;10(6):320 Current management of uninvestigated dyspepsia
- 39. ROME IV- 2016 Bước 1 Bước 2 Bước 3 Stanghellini et al, Gastroenterology 2016; 150: 1380-1392
- 40. TƯƠNG TÁC THUỐC
- 41. PPI Rabeprazole Omeprazole Lansoprazole Pantoprazole TƯƠNG TÁC QUA HỆ THỐNG CYP450 Diazepam –– ++ –– __ Warfarin – ++ –– __ Phenytoin –– ++ –– __ Theophylline –– –– ++ __ * Không ức chế, có thể giảmKhông ức chế, có thể giảm Humphries TJ, et al. Gastroenterology. 1996;110(Suppl):A138. Abstract. Humphries TJ, et al. Gut. 1996;39(Suppl 3):A47. Abstract. Ishizaki T, et al. Clin Pharmacol Ther. 1995;58:155-164. Andersson T. Clin Pharmacokinet. 1996;31:9-28. *
- 43. Clopidogrel và Aspirin giảm đáng kể nguy cơ stroke, MI, chết do ACS và/hoặc PCI, tăng nguy cơ XHTH (OR= 2.3, 95%CI =1.2-3.9) Kết hợp PPI : giảm nguy cơ XHTH tương tác thuốc (cùng chuyển hóa qua CYP2C19) giảm chuyển hóa Clopidogrel Omeprazole ảnh hưởng nhiều nhất Rabeprazole, Pantoprazole ít ảnh hưởng hơn Xem xét kháng tiểu cầu khác (ví dụ: Prasugrel, Ticagrelor) và / hoặc PPI khác (ví dụ: Pantoprazole, Rabeprazole) đối với BN có nguy cơ TM cao khi sử dụng đồng thời PPI. Expert Opin. Drug Metab. Toxicol. (2014) 10(2) PPI VÀ THUỐC KHÁNG TIỂU CẦU
- 44. Incidence of cardiovascular events and gastrointestinal bleeding in patients receiving clopidogrel with and without proton pump inhibitors: an updated meta-analysis Incidence of cardiovascular events and gastrointestinal bleeding in patients receiving clopidogrel with and without proton pump inhibitors: an updated meta-analysis Results: We included 39 studies with a total of 214,851 patients, of whom 73,731 (34.3%) received the combination of clopidogrel and a PPI. In pooled analysis, all-cause mortality, myocardial infarction, stent thrombosis and cerebrovascular accidents were more common in patients receiving both drugs. However, among 23,552 patients from eight RCTs and propensity-matched studies, there were no significant differences in mortality or ischaemic events between groups. The use of PPIs in patients taking clopidogrel was associated with a significant reduction in the risk of gastrointestinal bleeding. Conclusions: PPIs are a marker of increased cardiovascular risk in patients taking clopidogrel, rather than a direct cause of worse outcomes. The pharmacodynamic interaction between PPIs and clopidogrel most likely has no clinical significance. Furthermore, PPIs have the potential to decrease gastrointestinal bleeding in clopidogrel users Cardoso RN, Benjo AM, DiNicolantonio JJ,et al. Open Heart 2015;2:e000248.
- 45. TƯƠNG TÁC LIÊN QUAN ĐẾN pH DẠ DÀY
- 46. TÍNH AN TOÀN VÀ VẤN ĐỀ NGƯNG SỬ DỤNG PPI
- 47. 1. Laurent AL, et al. Clin Geriatr. 1999;7:27-33. 2. Keane W, et al. J Clin Pharmacol. 1999;39:927-933. 3. Hoyumpa AM, et al. Clin Ther. 1999;21:691-701. Effects Healthy elderly1 Renal impairment2 Hepatic impairment3 (mild-to-moderate) AUC doubled, Cmax↑60% * Similar to controls AUC and Cmax ↑20% Population Dosing No adjustment No adjustment No adjustment † * No evidence of drug accumulation † No data available with severe hepatic dysfunction, caution is advised in such patients PPIs Pharmacokinetics Special Populations
- 48. FDA Classification of PPI for Pregnancy PPI FDA class Comments Omeprazole C Embryotoxic and fetotoxic in animals. Case reports in human suggest similar concerns. Acceptable for use for aspiration prophylaxis in labour Lansoprazole B No fetal teratogenicity or harm. Limited human pregnancy date Use is acceptable for aspiration prophylaxis during pregnancy Rabeprazole B No fetal teratogenicity or harm. Limited human pregnancy date Use is acceptable for aspiration prophylaxis during pregnancy Pantoprazole B No fetal teratogenicity or harm. Limited human pregnancy date Use is acceptable for aspiration prophylaxis during pregnancy Esomeprazole B No fetal teratogenicity or harm. Limited human pregnancy date Use is acceptable for aspiration prophylaxis during pregnancy
- 51. NGUY CƠ KHI SỬ DỤNG PPI KÉO DÀI Giảm HCl Nhiễm trùng • Đường ruột : Clostridium difficile, SIBO • Viêm phổi : CAP, HCAP, HAP • SBP/ Xơ gan Giảm hấp thu: • Ca, UC hoạt động tạo cốt bào loãng xương, gãy xương • Mg, B12, Fe Tăng gastrin: gastric carcinoid tumors, u đại tràng Viêm teo DD mạn tăng nguy cơ K DD
- 52. CÁC NGUY CƠ KHI SỬ DỤNG PPI KÉO DÀI Gãy xương [1] FDA khuyến cáo… - Hông - Cột sống - Các vị trí RR 1.30; (95% CI 1.19-1.43) RR 1.56; (95% CI 1.31-1.85) RR 1.16; (95% CI 1.02-1.32) VPM tự phát/ XG [3] OR 2.77 (95% Cl 1.82–4.23) Nhiễm Clostridium difficile [4] Tái nhiễm FDA khuyến cáo… OR 1.7 (95% CI 1.5-2.9) OR 2.5 (95% CI 1.2-5.4) Viêm phổi (CAP/HCAP) [2] OR 1.27 (95% CI 1.11-1.46) (H2RA: OR 1.22) Viêm thận mô kẻ cấp [5] Hiếm Thiếu Fe, vit B12, Mg Dữ liệu hạn chế Viêm teo DD, K DD Dữ liệu hạn chế 1.Yu EW, Bauer SR, Bain PA, Bauer DC. Am J Med 2011; 124:519. 2. Eom CS, Jeon CY, Lim JW, et al. CMAJ 2011; 183:310. 3. rikudanathan G, Israel J, Cappa J, et al.. Int J Clin Pract 2011;65:674–678. 4.Kwok CS, Arthur AK, Anibueze CI, et al. Am J Gastroenterol 2012; 107:1011 5. Sampathkumar K, Ramalingam R, Prabakar A, Abraham A. Indian J Nephrol. 2013 Jul;23(4):304-7. .
- 53. Proton pump inhibitors versus histamine 2 receptor antagonists for stress ulcer prophylaxis in critically ill patients: a systematic review and meta-analysis Proton pump inhibitors versus histamine 2 receptor antagonists for stress ulcer prophylaxis in critically ill patients: a systematic review and meta-analysis Fourteen trials enrolling a total of 1,720 patients were included. PPI were more effective than H2RA at reducing clinically important upper gastrointestinal bleeding (RR 0.36; 95% CI 0.19-0.68; p = 0.002; I = 0%) and overt upper gastrointestinal bleeding (RR 0.35; 95% CI 0.21-0.59; p < 0.0001; I = 15%). There were no differences between PPI and H2RA in the risk of nosocomial pneumonia (RR1.06; 95% CI 0.73-1.52; p = 0.76; I = 0%), ICU mortality (RR 1.01; 95% CI 0.83-1.24; p = 0.91; I = 0%), or ICU length of stay (mean difference -0.54 days; 95% confidence interval -2.20 to 1.13; p = 0.53; I = 39%). Alhazzani W, et al. Crit Care Med. 2013 Mar;41(3):693-705
- 54. Proton pump inhibitors and the risk of hospitalisation for community-acquired pneumonia: replicated cohort studies with meta-analysis. Proton pump inhibitors and the risk of hospitalisation for community-acquired pneumonia: replicated cohort studies with meta-analysis. Of the 4 238 504 new users of NSAIDs, 2.3% also started a PPI. The cumulative 6-month incidence of HCAP was 0.17% among patients prescribed PPIs and 0.12% in unexposed patients. After adjustment, PPIs were not associated with an increased risk of HCAP (aOR=1.05; 95% CI 0.89 to 1.25). Histamine-2 receptor antagonists yielded similar results (aOR=0.95, 95% CI 0.75 to 1.21). CONCLUSIONS: Our study does not support the proposition of a pharmacological effect of gastric acid suppressors on the risk of HCAP. Filion KB, Chateau D, Targownik LE, et al. Gut. 2014 Apr;63(4):552-8
- 55. Tăng tiết acid bùng phát có thể xảy ra sau khi ngưng sử dụng PPI kéo dài (> 6 tháng) sau 14 ngày Bệnh nhân GERD hoặc khó tiêu giảm liều dần sau khi hết triệu chứng tối thiểu là ba tháng. BN điều trị loét tá tràng và dạ dày cấp 4-8 tuần không cần giảm liều Bệnh nhân điều trị H.Pylori không cần giảm liều PPI Đối với bệnh nhân dùng PPI liều trung bình đến cao (ví dụ omeprazole 40 mg/ngày hoặc 2 lần/ngày), giảm liều 50 % mỗi tuần liều thấp nhất liều thấp nhất trong một tuần ngưng thuốc. NGƯNG SỬ DỤNG PPI Inadomi JM, Jamal R, Murata GH, et al. Gastroenterology 2001; 121:1095.
- 56. KẾT LUẬN PPI là một thuốc điều trị rất hiệu quả trong nhiều bệnh lý liên quan đến tiết acid dạ dày Cần nắm vững các nguyên tắc sử dụng hợp lý để đạt hiệu quả điều trị tối ưu Các PPI tương đối an toàn, các nguy cơ không nhiều và chỉ gặp khi điều trị kéo dài Khi sử dụng PPI kéo dài cần giảm liều trước khi ngưng thuốc.
- 57. Cảm ơn sự theo dõi của các đồng nghiệp !
Notes de l'éditeur
- A resting parietal cell showing the tubulovesicular apparatus ( nang tiểu quản) in the cytoplasm and the intracellular canaliculus (kênh nội bào). B, An activated parietal cell that is secreting acid. The tubulovesicles have fused with the membranes of the intracellular canaliculus, which is now open to the lumen of the gland and lined with abundant long microvilli. Tb viền và bơm proton không hoạt động trước ăn và trong bữa ăn
- Three principal physiological stimuli: acetylcholine, histamine, and gastrin muscarinic M3 receptor enterochromaffin-like (ECL) cells Although interactions among these three pathways are coordinated to promote or inhibit hydrogen ion generation, histamine appears to represent the dominant route as gastrin stimulates acid secretion principally by promoting the release of histamine from ECL cellsBecause of the dominance of this pathway, H2-receptor blockade became the principal means by which acid secretion was inhibited in the mid-1970s
- The important thing with the PPIs is that they only inhibit active pumps First of all, it&apos;s important to remember that all of these drugs are pro-drugs that require activation before they can affect the proton pump. This activation occurs in the secretory canalicular space of the parietal cell. The activation of the PPI is really dependent upon two things: First, the pH in which you place the PPI; and second, the pKa of the PPI. Another feature that&apos;s very unique and important for PPIs is that the active moiety, the sulfonamide that is created as a result of the activation, concentrates up to 1000-fold higher in the secretory canaliculus, compared with the rest of the body. This concentration accounts for the very high potency of the PPIs and yet their limited side effects. Rabeprazole is a weak base, which means that it has an affinity for the highly acidic environment of the acid spaces of the parietal cell secretory canaliculi (the most acidic site in the body). Rabeprazole is inactive at neutral pH and becomes an active acid pump inhibitor only after rabeprazole gains a proton under these acidic conditions. The active form of the drug is a sulphenamide, which, being positively charged, does not pass readily through membranes and therefore remains within the secretory canaliculi, close to the luminal membrane of the parietal cell. Sulphenamide molecules reacts with a cysteine-SH group on the luminal face of H+,K+-ATPase (proton pump). The formation of this complex permits long-lasting acid inhibition, irrespective of secretory stimuli.
- The important thing with the PPIs is that they only inhibit active pumps
- The pKas of PPIs range from approximately 4 to 5, and drugs that have higher pKas have a more rapid and more complete activation, particularly as the pH of the canalicular space rises above 1 to 2.
- This slide demonstrates the differences in activation times of the various PPIs. The pKas of the PPIs range from 5.0 for rabeprazole (Aciphex) down to about 3.8 for pantoprazole (Protonix). At a pH of 1.2, which would occur in the canalicular space during eating, all of the PPIs are very rapidly activated. However, once the patient stops eating, the pH in the canalicular space rises. At a pH of 5.1, notice that rabeprazole, with a pKa of 5, is still rapidly activated. Look instead at pantoprazole, which has a pKa of 3.8. When the pH in the canalicular space is 5, the activation time of pantoprazole has slowed down to nearly 300 minutes. The differences we see between the PPIs and their activation time are most important when one considers the onset of effect of the drugs. These differences might be especially important if one is trying to get symptoms under control very quickly. In addition, short-duration therapy, for example the treatment of H. pylori with PPIs, also might benefit from a rapid onset of action The differences we see between the PPIs and their activation time are most important when one considers the onset of effect of the drugs. These differences might be especially important if one is trying to get symptoms under control very quickly. In addition, short-duration therapy, for example the treatment of H. pylori with PPIs, also might benefit from a rapid onset of action.
- The half-life of all the PPIs is relatively short, a half hour to 2 hours. Oral administration is relatively irrelevant. We&apos;re interested in the duration of effect, so the elimination half-life has little to do with it. P.P.I - Irreversible inhibitors of H+K+ATPase Ability to maintain intragastric pH &gt; 4 in 10-14 hrs Single PPI will not inhibit all pumps. Second dose could be taken before evening meal Nocturnal acid breathrough
- Omeprazole, esomeprazole (Nexium), and pantoprazole are predominantly metabolized by enzyme 2C19. Lansoprazole is about equally metabolized by 2C19 and 3A4; rabeprazole is somewhat unique in that most of its metabolism does not go down a cytochrome P450 pathway.
- There are two genes that code for 2C19; having both genes makes you a homozygote extensive metabolizer. Having one functional and one nonfunctional gene makes you a heterozygote extensive metabolizer, and having two nonfunctional genes makes you a poor metabolizer for 2C19.
- A compilation of clinical data of CYP genotype distribution among different ethnic groups clearly showed that the incidence of extensive metabolisers in Asians is much lower than Caucasian population. In addition, it is also clear that in the Asian population, there is greater variability and hence it is likely that efficacy of drug metabolized by CYP2C19 would be unpredictable. 80% benh nhân ngươi châu A chưa đu lieu vì ho co kieu hình di truyen EM, IM. Neu tăng lieu, * 20% nguy cơ qua lieu, * Tac dung phu cao Rapid metabolizers have lower blood concentration of PPIs; slow metabolizers have relatively higher concentration of PPIs. Of course, the response to PPIs varies with the amount of drug present in the patient. Notice that most Caucasians are extensive metabolizers of 2C19, with only about 3% being poor metabolizers. Asians are more often slow metabolizers of 2C19, about 20%, due to a higher occurrence of dysfunctional gene
- Omeprazole: Nhóm mang kiểu hình EM cho tỉ lệ còn loét cao hơn nhiều so với PM, IM (Hiệu quả điều trị phụ thuộc kiểu hình CYP2C19) Rabeprazole: Không có khác biệt có ý nghĩa về tỉ lệ còn loét sau 2 tuần ở 3 dạng kiểu hình PM, IM & EM (Hiệu quả điều trị không phụ thuộc kiểu hình CYP2C19)
- The explanation for this lies in the alteration in metabolism and clearance with repeated dosing of esomeprazole. After the first dose, there is metabolism by CYP2C19 and CYP3A. This leads to esomeprazole sulphone, and this esomeprazole sulphone inhibits the CYP2C19 pathway; therefore, almost the entire metabolism goes free of CYP3A. This inhibition lasts for more than 24 hours and causes progressive inhibition of clearance of succeeding daily doses of esomeprazole.
- PPIs hiệu quả 1, không bị dung nạp thuốc như H2-antagonists
- HP exists between the epithelial cell layers and the mucus in the stomach. H. pyloriis very sensitive to pH and is able to move throughout this layer as the pH changes. It&apos;s also important to notice that in the typical treatment of H. pylori with PPIs and antibiotics, the delivery of the antibiotics to the H. pylori is via the bloodstream. PPIs can have some direct effect on H. pylori. However, they do not kill the bacteria. H. pylori produces urease, which is one of the ways in which it controls the pH in its immediate neighborhood. The production of urease can be inhibited by PPIs and may represent one of the direct ways that PPIs alter H. pylori activity and perhaps change its sensitivity to antibiotics.
- This meta-analysis here shows that there&apos;s just no comparison, the PPIs are wonderful drugs and far superior to the H2 blockers. They work great. Not only that, but they work no matter how severe the erosive GERD
- After exclusion of drug-induced dyspepsia, the choice of empirical therapy includes testing for and eradication of Helicobacter pylori in regions with high seroprevalence of H. pylori positivity and, in regions with low seroprevalence, selection of prokinetic or PPI therapy based on the predominance of symptoms (postprandial distress versus pain). *First choice determined by population prevalence of H. pylori infection. The symptoms of this syndrome often overlap with those of GERD and IBS, making its management far from simple. If Helicobacter pylori infection is diagnosed in patients with functional dyspepsia, it should be treated. In patients with mild or intermittent symptoms, reassurance and lifestyle advice might be sufficient; in patients not responding to these measures, or in those with more severe symptoms, drug therapy should be considered. Both PPIs and prokinetics can be used in initial empirical pharmacotherapy based on symptom patterns--a PPI is more likely to be effective in the presence of retrosternal or epigastric burning or epigastric pain, whereas a prokinetic is more effective in dyspepsia with early satiation or postprandial fullness. Although combinations of PPIs and prokinetics might have additive symptomatic effects, single-drug therapy is initially preferable. Antidepressants or referral to a psychiatrist or psychotherapist can be considered in nonresponders and in those whose symptoms have a marked effect on daily functioning. Despite extensive research, functional dyspepsia treatment often remains unsatisfactory. Better characterization of dyspeptic subgroups and understanding of underlying mechanisms will enable treatment advances to be made in the future.
- An toàn Ức chế CYP 450 & ảnh hưởng lên chuyển hóa của warfarin, phenytoin, etc Pantoprazole & Rabeprazole: ko giao thoa thuốc Unlike other PPIs, rabeprazole is metabolized mainly via a nonenzymatic reduction to a thioether compound with minor involvement of the cytochrome P450 (CYP450) enzyme system in the liver. (1) Accordingly, studies have indicated that the potential for rabeprazole to interact with other drugs metabolized by this system is low. Studies in healthy humans have shown that rabeprazole does not interact with drugs that undergo extensive hepatic metabolism, including theophylline, warfarin, phenytoin, and diazepam. (2-4) No interactions with theophylline and warfarin have been noted for other PPIs as well. (5) However, omeprazole has been found to have an inhibitory interaction with diazepam, phenytoin, and R-warfarin (the inactive isomer of warfarin). Lansoprazole does not appear to interact with diazepam, warfarin, phenytoin, or theophylline. Ishizaki T, Horai Y. Cytochrome P450 and the metabolism of proton pump inhibitors – emphasis on rabeprazole. Aliment Pharmacol Ther. 1999;13(Suppl):27-36. Humphries TJ, Nardi RV, Spera AC, Lazar JD, Laurent AL, Spanyers SA. Coadministration of rabeprazole sodium (E3810) does not affect the pharmacokinetics of anhydrous theophylline or warfarin. Gastroenterology. 1996;110(Suppl):A138. Abstract. Humphries TJ, Nardi RV, Lazar JD, Spanyers SA. Drug-drug interaction evaluation of rabeprazole sodium: a clean/expected slate? Gut. 1996;39(Suppl 3):A47. Abstract. Ishizaki T, Chiba K, Manabe K, et al. Comparison of the interaction potential of a new proton pump inhibitor, E3810, versus omeprazole with diazepam in extensive and poor metabolizers of S-mephenytoin 4’-hydroxylation. Clin Pharmacol Ther. 1995;58:155-164. Andersson T. Pharmacokinetics, metabolism, and interactions of acid pump inhibitors: focus on omeprazole, lansoprazole, and pantoprazole. Clin Pharmacokinet. 1996;31:9-28.
- Clopidogrel is converted to its active metabolite by cytochrome P450 (CYP) enzymes. Clopidogrel users with decreased CYP2C19 function have less inhibition of platelet aggregation and increased cardiovascular (CV) events. As PPI metabolism also involves CYP2C19, it was hypothesized that competition by PPIs might interfere with clopidogrel ’ s action. Omeprazole, but not other PPIs, worsens surrogate markers of clopidogrel efficacy.
- The mechanism of increased CV risk in patients receiving a PPI is most likely related to the difference in baseline characteristics between users and non-users of clopidogrel. In the study by Charlotet al, 73 patients who received a PPI were on average 3 years older than the comparison group and also had a higher prevalence of diabetes with complications, chronic kidney injury and cerebrovascular disease at baseline. In Bhurke et al, 30 patients taking clopidogrel had a higher Charlson comorbidity index at baseline, as well as a higher prevalence of heart failure. Similarly, the majority of unadjusted studies that reported an increased risk of CV events in PPI users had an unbalanced distribution of baseline characteristics, with sicker patients in the PPI group. 31 52
- nồng độ thuốc theo thời gian (AUC)
- Pharmacokinetic studies indicate that, based on once daily dosing with 20 mg, no dosage adjustment is required when rabeprazole is used in healthy elderly patients, in patients with renal impairment, and in those with mild-to-moderate hepatic impairment. (1-3) The pharmacokinetics of rabeprazole in such patients were evaluated in separate, single-center, comparator studies with equal numbers of special population and control groups. A comparison of pharmacokinetic parameters in 20 healthy patients age 65 and 20 healthy patients aged 19-30 years who received 20 mg rabeprazole daily for 7 days showed some pharmacokinetic differences in elderly patients (significantly greater AUC and Cmax values and shorter Tmax values). However, rabeprazole was well tolerated in the older patients and there was no evidence of drug accumulation. Safety profiles showed no differences between age groups. Therefore, no dosing adjustment is necessary in healthy elderly patients. (1) The pharmacokinetics of rabeprazole were also studied in 10 patients with renal disease (2) and 10 patients with hepatic disease (3) who received a single 20-mg dose. Renal patients had values similar to controls. Hepatic patients had significantly greater AUC, Cmax, and T1/2 values. These changes are expected and have been seen with other PPIs. (2,3) In patients with renal impairment and in those with mild-to-moderate hepatic impairment, no dosage adjustment is required for patients receiving 20 mg rabeprazole qd. (2,3) Caution is advised, however, when using rabeprazole in patients with severe hepatic dysfunction. Laurent AL, Merritt GJ, Setoyama T, Humphries TJ. Rabeprazole: pharmacokinetics and safety in the elderly. Clin Geriatr. 1999;7:27-33. Keane W, Swan S, Grimes I, Humphries TJ. Rabeprazole: well tolerated in patients with stable, end-stage renal failure. J Clin Pharmacol. 1999;39:927-933. Hoyumpa AM, Trevino-Alanis H, Grimes I, Humphries TJ. Rabeprazole: pharmacokinetics in patients with stable, compensated cirrhosis. Clin Ther. 1999;21:691-701.
- In one study, for example, atrophy developed in over 30 percent of patients after omeprazole therapy for a five-year period, changes not evident in a cohort of Scandinavians treated with anti-reflux surgery [ 94 ]. However, since the omeprazole-treated patients developed atrophy only in the presence of a concomitant H. pylori infection, it was suggested that only the H. pylori infected group was at risk. This recommendation was supported by a subsequent controlled trial involving 155 patients who were randomly assigned to anti-reflux surgery or omeprazole [ 95 ]. After three years, no significant differences were observed in the development of gastric glandular atrophy or the occurrence of intestinal metaplasia, irrespective of H. pylori status. Although there is concern regarding evidence that PPIs may reduce the bioavailability of ingested vitamin C, long-term follow-up evaluation of patients taking chronic daily PPIs for up to 7 years has not shown iron absorption to be clinically apparent.[4,5] Further, most cases of iron malabsorption can be managed clinically with the use of medicinal iron supplements that are absorbed independent of gastric acid and vitamin C.[6] Despite this, in 2010 the FDA issued a product label warning for all PPIs because of clinical reports inferring increased risk for bone fractures. The FDA revised this warning in March of 2011 to release over-the-counter PPIs, which are intended for short-term use (ie, 2 weeks) for up to 3 cycles per year.[10] From HCV to EoE and IBD: Best of ACG 2014 TARGET 3: Rifaximin Safe to Reuse for Irritable Bowel New Guidelines Issued on Bowel Prep for Colonoscopy Intermittent PPI Therapy Effective for High-Risk Bleeding Ulcers Clinical Gastroenterology and Hepatology Reported Side Effects and Complications of Long-term Proton Pump Inhibitor Use Dissecting the Evidence David A. Johnson, Edward C. Oldfield IV DisclosuresClin Gastroenterol Hepatol. 2013;11(5):458-464. Print Email Introduction Effects on Vitamin and Mineral Absorption Proton Pump Inhibitors and Infection Methotrexate Conclusions References Effects on Vitamin and Mineral Absorption Iron Nonheme iron (ferric, Fe 3+) constitutes the majority of dietary iron consumed. To be absorbed by duodenal enterocytes, this iron subsequently must undergo a reduction into the ferrous state (Fe 2+), mediated by hydrochloric acid released from the stomach. In vivo data have shown that this absorption is related directly to the release of ferric iron by gastric juice.[2] There also is evidence suggesting that this process is related more specifically to the vitamin C released in gastric secretions, which acts as a reducing agent and prevents the formation of insoluble compounds.[3] Although there is concern regarding evidence that PPIs may reduce the bioavailability of ingested vitamin C, long-term follow-up evaluation of patients taking chronic daily PPIs for up to 7 years has not shown iron absorption to be clinically apparent.[4,5] Further, most cases of iron malabsorption can be managed clinically with the use of medicinal iron supplements that are absorbed independent of gastric acid and vitamin C.[6] To date, only one study has addressed the association between PPI use and the development of iron-deficiency anemia. This study found that among patients receiving chronic PPI therapy there was a significant decrease in all hematologic indexes from baseline.[7] Despite these findings, the study suffered from a number of drawbacks including small sample size, limited serial ferritin levels to properly determine iron-deficiency anemia, and the inability to exclude a number of potential confounders. Given these limitations, this study did not offer a definitive answer on the topic. Bottom Line. Although it is conceivable that PPI therapy may reduce absorption of nonheme iron and retard iron pool replenishment, this effect has not been well studied or evident from widespread use in clinical practice. Calcium The absorption of dietary calcium is believed to be mediated by gastric acid release of ionized calcium from insoluble calcium salts. Hence, there have been concerns that hypochlorhydric states, in particular those induced by PPIs, may impair calcium absorption; however, there are limited data to support this claim; in fact 2 high-quality studies showed no adverse effect.[8,9] Overall, the studies suggested that calcium absorption potentially was affected negatively only in the setting of reduced acid secretion when ingested calcium carbonate was provided in the fasting state. Despite this, in 2010 the FDA issued a product label warning for all PPIs because of clinical reports inferring increased risk for bone fractures. The FDA revised this warning in March of 2011 to release over-the-counter PPIs, which are intended for short-term use (ie, 2 weeks) for up to 3 cycles per year.[10] Literature analysis of PPI use and bone fractures revealed conflicting results. The earlier published reports linking PPI use to the development of hip fractures were observational case-control studies and thereby have greater potential for bias and therefore less accurate estimates. In addition, the strength of association in the PPI studies has been of low magnitude. Given that the estimates and even the upper bounds of most of the 95% confidence intervals (CIs) of the odds ratios (ORs) were well below 2, there is a strong possibility these differences could have been related to the channeling bias inherent in observational studies.[11] For example, a prospective study including 79,899 postmenopausal women from the US Nurse&apos;s Health Study showed that despite an OR of 1.36 (95% CI, 1.13–1.63) for PPI use, when accounting for a history of smoking, there was no significant association between PPI use and fracture risk (OR, 1.06; 95% CI, 0.77–1.46).[12] More recent studies have shown an association between PPI use and hip fracture risk, yet there was no evidence to suggest a duration effect from long-term PPI use (OR, 1.30; 95% CI, 0.98–1.70) as compared with short-term use (OR, 1.24; 95% CI, 1.19–1.28).[13] This suggests that the observed association likely was owing to confounding factors. In addition, other recent cross-sectional, longitudinal, and prospective observational reports did not support the prior reported association.[14,15] Even more convincing evidence supporting the lack of harm comes from a recently published population-based sample of Canadians who underwent bone mineral density (BMD) testing of the femoral neck, total hip, and lumbar spine at baseline, and then again at 5 and 10 years. In all, 8340 subjects were included in the baseline analysis, with 4512 (55%) undergoing year 10 BMD testing. After adjusting for potential confounders, PPI use was associated with significantly lower baseline BMD at the femoral neck and total hip. By multivariate linear regression, however, there was no evidence of any acceleration in covariate-adjusted BMD loss at any measurement site after 5 and 10 years of follow-up evaluation. Therefore, PPI users had lower BMD at baseline than PPI nonusers, but PPI use over 10 years did not appear to be associated with accelerated BMD loss. It would be paradoxic that there would be an element of risk at entry and that longer duration of exposure would not amplify any risk effect.[16] Contrary to their purported role in increasing the risk for fractures, PPIs actually may increase bone density through their impairment of osteoclast activity. Osteoclasts contain vacuolar proton pumps necessary for acidification at the ruffled border, which facilitates dissolution of the bone matrix and its subsequent resorption.[17] Patients on PPIs have decreased levels of urinary calcium and hydroxyproline, suggesting decreased osteoclast activity and bone resorption. In addition, these patients have increased levels of the osteoblast precursors, osteocalcin and tissue-resistant alkaline phosphatase, suggesting new bone formation.[18] Bottom Line. There is no good evidence to establish that PPI use has a significant risk for bone density loss or osteoporotic-related fractures. Accordingly, the data on bone density loss and osteoporotic fractures would not support that PPI therapy be discontinued in patients taking PPIs for appropriate indications at appropriate doses. Supplemental calcium is not recommended or justified solely because of PPI use. Magnesium There have been several (total, &lt;50) cases of hypomagnesemia that were associated with long-term PPI use.[19–21] The patients generally presented with profound hypomagnesemia and typically required hospitalizatio. This alert suggested that health care providers should consider checking magnesium levels in patients who are anticipated to be on long-term PPIs. The mechanism for the magnesium depletion is not known Vitamin B12 Gastric acid is involved in the absorption of B12 by facilitating its release from dietary protein, such that B12 can bind to R proteins. This B12–R protein complex is broken down in the duodenum and, subsequently, B12 can be absorbed in the terminal ileum once bound to intrinsic factor. Because B12 absorption is dependent on gastric acid, theoretically, long-term PPI use may impair an individual&apos;s absorptive ability. Bottom Line. Studies examining the potential relationship between PPIs and B12 have shown conflicting results, and a prospective trial is needed to conclude any causative effect.[25,26,27,28,29] In addition, to date no studies have provided a longitudinal evaluation showing alterations of specific metabolic intermediates (eg, methylmalonate and homocysteine), which can accumulate with this deficiency. Further, because hypochlorhydria would only impair the release of B12 from dietary protein, absorption of oral B12 supplements should be unimpaired
- *A meta-analysis that included 11 cohort and case-control studies (2 yrs) **One large case-control study found an increased risk of CAP only among patients who started a PPI within the previous 30 days and particularly in those who initiated therapy within the previous 48 hours This class of medication has been available for commercial use for nearly 25 years Given the potential risk of C. difficile infection, the FDA has also recommended that providers prescribe the lowest dose and shortest duration of PPI therapy appropriate to the condition being treated. The FDA also recommends that healthcare professionals who prescribe PPIs consider whether a lower dose or shorter duration of therapy would adequately treat the patient&apos;s condition. The FDA revised this warning in March of 2011 to release over-the-counter PPIs, which are intended for short-term use (ie, 2 weeks) for up to 3 cycles per year. The 2013 ACG guidelines on GERD state that existing osteoporosis is not a contraindication to PPI therapy.13 Patients with osteoporosis may remain on PPI therapy unless another risk factor for hip fracture exists.13 Furthermore, in March 2011, the FDA modified its osteoporosis and fracture warning. It was concluded that OTC products do not warrant label changes to include warnings of fracture risk. If calcium supplementation is indicated, use of calcium citrate is the preferred calcium supplement in patients taking PPIs, as it can be absorbed in the absence of an acidic environment.1 An FDA Drug Safety Communication warns of the risks of hypomagnesemia and recommends that providers monitor serum magnesium levels in patients taking PPIs.21 The FDA suggests that providers obtain serum magnesium levels prior to initiation of therapy and periodically thereafter for patients who will continue prolonged treatment and for patients who take medications that also cause hypo-magnesemia. The most recent meta-analysis (9 studies, 120,863 patients) further delineated the relative risks of PPI use and CAP, finding that there was no association between CAP and PPI use longer than 180 days (OR, 1.10; 95% CI, 1.00–1.21); rather, the association between PPI use and CAP was strongest for PPI use of fewer than 30 days (OR, 1.65; 95% CI, 1.25–2.19) and high-dose PPIs (OR, 1.50; 95% CI, 1.33–1.68).[47] Also supporting the association between short-term PPI use and CAP, a database review of 71,985 outpatient prescriptions for PPIs in the New England Veterans Healthcare System found that PPI use between 1 and 15 days had increased risk for CAP over longer PPI exposures.[48] Trikudanathan G, Israel J, Cappa J, et al. Association between proton pump inhibitors and spontaneous bacterial peritonitis in cirrhotic patients–a systematic review and meta-analysis. Int J Clin Pract 2011;65:674–678. The most recent data from Bajaj et al[66] suggest that H2RAs do not have this relative risk. Accordingly, if the patient has decompensated cirrhosis and needs continued acid-reduction therapy, it is reasonable to try switching to an H2RA and monitor the clinical effectiveness of the change in therapy.