How Do Antacids Work?

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Please refer to the appropriate style manual or other sources if you have any questions. </div> <div class="label mt-20 mb-10">Select Citation Style</div> <select class="js-citation-format-select form-select"> <option selected value="mla">MLA</option> <option value="apa">APA</option> <option value="chicago">Chicago Manual of Style</option> </select> <div class="citation font-serif border rounded p-15 mt-20" data-authors="Rogers, Kara" data-authors-initial="Rogers, K." data-title="How Do Antacids Work?" data-published-date="4 Feb. 2023" data-url="https://www.britannica.com/story/how-do-antacids-work" > <div class="citation-text"></div> </div> <button class="js-copy-citation-button mt-20 btn btn-xs btn-outline-blue border shadow-sm pr-10" > <em class="material-icons md-icon ml-n10 my-n5 mr-5" data-icon="file_copy"></em> <span class="js-citation-status-text">Copy Citation</span> </button> </div> </div> </div> <div> <button class="js-share-modal-button js-modal gtm-topic-tool btn btn-xs btn-outline-blue border shadow-sm pr-10" data-modal=".md-share-modal"> <em class="material-icons md-icon ml-n10 my-n5 mr-5" data-icon="share"></em> Share </button> <div class="md-share-modal size-lg d-none qa-share-modal"> <div class="md-modal-body"> <div class="h2 font-serif d-flex align-items-center pb-15 border-bottom"> <em class="material-icons text-blue mr-10" data-icon="share"></em> Share </div> <div class="label my-20">Share to social media</div> <div class="md-social-toolbar-circle d-flex align-items-start inverted" data-value="share" title="How Do Antacids Work?" data-url="https://www.britannica.com/story/how-do-antacids-work" > <a class="social-icon facebook justify-content-center d-flex align-items-center align-self-center" data-provider="facebook" href="https://www.facebook.com/BRITANNICA/" target="_blank" rel="noopener"><span>Facebook</span></a> <a class="social-icon x justify-content-center d-flex align-items-center align-self-center" data-provider="x" href="https://x.com/britannica" target="_blank" rel="noopener"><span>X</span></a> </div> <div class="label pt-20 mt-20 mb-5 border-top">URL</div> <a class="font-serif text-truncate d-inline-block" href="https://www.britannica.com/story/how-do-antacids-work">https://www.britannica.com/story/how-do-antacids-work</a> </div> </div> </div> </div> <div class="md-byline module-spacing font-12"> <div class="font-serif font-12"> <span class="written-by text-gray-700"> Written by </span> <div class="editor-popover popover p-0"> <a class="d-block p-20 qa-editor-popup gtm-byline font-12 byline-contributor" href="/editor/Kara-Rogers/6713" > <div class="editor-title font-16 font-weight-bold">Kara Rogers</div> <div class="editor-description font-12 font-serif mt-5 clamp-description text-black">Kara Rogers is the senior editor of biomedical sciences at Encyclopædia Britannica, where she oversees a range of content from medicine and genetics to microorganisms. She joined Britannica in 2006 and...</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link gtm-byline font-12 byline-contributor text-decoration-underline"> Kara Rogers</span></div> <div class="font-serif font-12 text-gray-700"> <span class="qa-fact-checked-by">Fact-checked by</span> <div class="editor-popover popover p-0"> <a class="d-block p-20 qa-editor-popup font-12" href="/editor/The-Editors-of-Encyclopaedia-Britannica/4419" > <div class="editor-title font-16 font-weight-bold">The Editors of Encyclopaedia Britannica</div> <div class="editor-description font-12 font-serif mt-5 text-black">Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree. They write new content and verify and edit content received from contributors.</div> </a> <div data-popper-arrow></div> </div> <span class="btn btn-link editor-link p-0 qa-byline-link font-12 "> The Editors of Encyclopaedia Britannica</span></div></div> </div> <article class="topic-content content mt-20"><figure class="md-assembly md-feature-assembly print-false" data-type="1" data-descid="1"><div class="md-assembly-wrapper card-media" data-type="image"><a href="https://cdn.britannica.com/30/130830-050-6D88060B/Tums-calcium-carbonate-ingredient.jpg" target="_blank" class="gtm-assembly-link position-relative d-flex align-items-center justify-content-center " data-href="*"><img src="https://cdn.britannica.com/30/130830-050-6D88060B/Tums-calcium-carbonate-ingredient.jpg?w=600&q=60" alt="Photo of the antacid Tums" data-width="695" data-height="600" loading="eager"><button class="magnifying-glass btn btn-circle position-absolute shadow btn-white top-10 right-10" aria-label="Zoom in"><em class="material-icons link-blue" data-icon="zoom_in"></em></button></a></div><figcaption class=""><div class="md-assembly-caption text-muted font-14 font-serif line-clamp"><span><button class="js-more-btn d-none btn btn-unstyled font-12 bg-white js-content" aria-label="Toggle more/less fact data"><span class="link-blue">(more)</span></button></span></div><cite class="credit d-block mt-5">© Linda Muir/Shutterstock.com</cite></figcaption></figure> <p class="topic-paragraph"><a href="https://www.britannica.com/science/antacid" class="md-crosslink " data-show-preview="true">Antacids</a> containing substances such as <a href="https://www.britannica.com/science/sodium-bicarbonate" class="md-crosslink " data-show-preview="true">sodium bicarbonate</a>, magnesium hydroxide, or calcium carbonate fundamentally are <a href="https://www.britannica.com/science/base-chemical-compound" class="md-crosslink " data-show-preview="true">bases</a>. They work by counteracting or neutralizing gastric <a href="https://www.britannica.com/science/acid" class="md-crosslink " data-show-preview="true">acids</a> to relieve the discomfort caused by gastric acidity. These medications typically are taken when gastric acidity is most likely to be increasing, such as within an hour or two after a meal and at bedtime. </p><span class="MOD1"></span> <p class="topic-paragraph">Other antacids, such as <a href="https://www.britannica.com/science/H2-receptor-antagonist" class="md-crosslink " data-show-preview="true">histamine receptor antagonists</a> (e.g., ranitidine and cimetidine) and <a href="https://www.britannica.com/science/proton-pump-inhibitor" class="md-crosslink " data-show-preview="true">proton-pump inhibitors</a> (e.g., omeprazole), work by reducing <a href="https://www.britannica.com/science/human-digestive-system/Gastric-secretion" class="md-crosslink " data-show-preview="true">acid secretion</a> in the stomach. They do so by blocking the action of hormones on the acid-secreting parietal cells of the stomach. These drugs take additional time to work but have long-lasting effects relative to traditional antacids.</p><span class="MOD2"></span> <span class="AM-END-OF-ARTICLE am-inline"></span></article> </div> </div> </div> <aside class="cm-rightrail d-none d-md-block ad-rail"></aside> </div> </div> </div> </div> </main> <div class="grid gx-0"> <div class="col"> <div class="md-loading hidden display-4 font-weight-normal"></div> <div class="text-center my-20 mb-100"> <button class="md-infinite-load-next btn btn-blue" data-value="next-page">Load More</button> </div> </div> <div class="col-md-da-320 hidden-xs"> </div> </div> </div> </div> </main> <div id="md-footer"></div> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <script type="text/javascript" id="_informizely_script_tag"> var IzWidget = IzWidget || {}; (function (d) { var scriptElement = d.createElement('script'); scriptElement.type = 'text/javascript'; scriptElement.async = true; scriptElement.src = "https://insitez.blob.core.windows.net/site/f780f33e-a610-4ac2-af81-3eb184037547.js"; var node = d.getElementById('_informizely_script_tag'); node.parentNode.insertBefore(scriptElement, node); } )(document); </script>  <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"Story","templateName":"COMPANION","pageNumber":1,"pagesTotal":11,"pageId":12898,"pageLength":null,"initialLoad":true,"lastPageOfScroll":false} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-133/js/libs/jquery-3.5.0.min.js?v=3.133.9"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-133/dist/story-page.js?v=3.133.9' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"B","adLeg":"B","userType":"ANONYMOUS","pageType":"Story","pageSubtype":"COMPANION","articleTemplateType":null,"gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>

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How Do Antacids Work? | Britannica