An antacid is a substance that neutralizes stomach acidity and is used to relieve heartburn, indigestion, or an upset stomach. [1] Some antacids have been used in the treatment of constipation and diarrhea. [2] Marketed antacids contain salts of aluminum, calcium, magnesium, or sodium. [2] Some preparations contain a combination of two salts, such as magnesium carbonate and aluminum hydroxide (e.g., hydrotalcite). [3]
Antacids are available over the counter and are taken by mouth to quickly relieve occasional heartburn, the major symptom of gastroesophageal reflux disease and indigestion. Treatment with antacids alone is symptomatic and only justified for minor symptoms. [4] Alternative uses for antacids include constipation, diarrhea, hyperphosphatemia, and urinary alkalization. [2] Some antacids are also used as an adjunct to pancreatic enzyme replacement therapy in the treatment of pancreatic insufficiency. [5]
Non-particulate antacids (sodium citrate) increase gastric pH with little or no effect on gastric volume, and therefore may see some limited use in pre-operative procedures. Sodium citrate should be given within 1 hour of surgery to be the most effective. [6]
Conventional effervescent tablets contain a significant amount of sodium and are associated with increased odds of adverse cardiovascular events according to a 2013 study. [7] Alternative sodium-free formulations containing magnesium salts may cause diarrhea, whereas those containing calcium or aluminum may cause constipation. [8] : Table 2 Long-term use of antacids containing aluminum may increase the risk of developing osteoporosis. [9] In vitro studies have found a potential for acid rebound to occur due to antacid overuse, however the significance of this finding has been called into question. [10] [11]
When an excess amount of acid is produced in the stomach, the natural mucous barrier that protects the lining of the stomach can degrade, leading to pain and irritation.[ citation needed ] There is also potential for the development of acid reflux, which can cause pain and damage to the esophagus.[ citation needed ] Antacids contain alkaline ions that chemically neutralize stomach gastric acid, reducing damage to the stomach lining and esophagus, and relieving pain. [1] Some antacids also inhibit pepsin, an enzyme that can damage the esophagus in acid reflux. [2] [12]
Antacids do not directly inhibit acid secretion, and thus are distinct from acid-reducing drugs like H2-receptor antagonists or proton pump inhibitors. [4] Antacids do not kill the bacteria Helicobacter pylori , which causes most ulcers. [4]
Antacids are known to interact with several oral medications, including fluoroquinolone and tetracycline antibiotics, iron, itraconazole, and prednisone. [13] Metal chelation is responsible for some of these interactions (e.g. fluoroquinolones, tetracyclines), leading to decreased absorption of the chelated drug. Some interactions may be due to the pH increase observed in the stomach following antacid ingestion, leading to increased absorption of weak acids, and decreased absorption of weak bases.[ citation needed ] Antacids also cause an increase in pH of the urine (alkalization), which may cause increased blood concentrations of weak bases, and increased excretion of weak acids. [14]
A proposed method to mitigate the effects of stomach acidity and chelation on drug absorption is to space out the administration of antacids with interacting medications by at least two hours, [15] however this method has not been well studied for drugs affected by urine alkalization. [13]
There are concerns regarding interactions between delayed-release tablets and antacids, as antacids may increase the stomach pH to a point at which the coating of the delayed-release tablet will dissolve, leading to degradation of the drug if it is pH sensitive. [14]
Antacids may be formulated with other active ingredients such as simethicone to control gas, or alginic acid to act as a physical barrier to acid. [16]
Several liquid antacid preparations are marketed. Common liquid preparations include milk of magnesia and magnesium/aluminum combinations. A potential advantage of using a liquid preparation over a tablet is that liquids may provide quicker relief, however this may coincide with a shorter duration of action. [17]
Chewable tablets are one of the most common forms of antacids, most frequently made from carbonate or hydroxide salts, and are readily available over the counter. Upon reaching the stomach, the powdered antacid salts bind to hydronium (H+) ions, producing chloride salts, carbon dioxide, and water. This process reduces the concentration of H+ ions in the stomach, raising the pH and neutralizing the acid. [8] : Figure 1 Common carbonate salts available in tablet form include those of calcium, magnesium, aluminum, and sodium. [13]
Some common American brands are Tums, Gaviscon chewable tablets, and Maalox chewable tablets. [18]
Effervescent tablets are tablets which are designed to dissolve in water, and then release carbon dioxide. [19] [20] [21] Common ingredients include citric acid and sodium bicarbonate, which react when in contact with water to produce carbon dioxide. Effervescent antacids may also contain aspirin, [22] sodium carbonate, or tartaric acid. [23] Those containing aspirin may cause further gastric irritation and ulceration due to aspirin's effects on the mucous membrane of the stomach. [24]
Some brands include Alka-Seltzer, Gaviscon, Tums, Gelusil and Eno. [25] [26] [27]
Heartburn, also known as pyrosis, cardialgia or acid indigestion, is a burning sensation in the central chest or upper central abdomen. Heartburn is usually due to regurgitation of gastric acid into the esophagus. It is the major symptom of gastroesophageal reflux disease (GERD).
Aluminium hydroxide, Al(OH)3, is found in nature as the mineral gibbsite and its three much rarer polymorphs: bayerite, doyleite, and nordstrandite. Aluminium hydroxide is amphoteric, i.e., it has both basic and acidic properties. Closely related are aluminium oxide hydroxide, AlO(OH), and aluminium oxide or alumina, the latter of which is also amphoteric. These compounds together are the major components of the aluminium ore bauxite. Aluminium hydroxide also forms a gelatinous precipitate in water.
Magnesium hydroxide is an inorganic compound with the chemical formula Mg(OH)2. It occurs in nature as the mineral brucite. It is a white solid with low solubility in water (Ksp = 5.61×10−12). Magnesium hydroxide is a common component of antacids, such as milk of magnesia.
Gastroesophageal reflux disease (GERD) or gastro-oesophageal reflux disease (GORD) is a chronic upper gastrointestinal disease in which stomach content persistently and regularly flows up into the esophagus, resulting in symptoms and/or complications. Symptoms include dental corrosion, dysphagia, heartburn, odynophagia, regurgitation, non-cardiac chest pain, extraesophageal symptoms such as chronic cough, hoarseness, reflux-induced laryngitis, or asthma. In the long term, and when not treated, complications such as esophagitis, esophageal stricture, and Barrett's esophagus may arise.
H2 antagonists, sometimes referred to as H2RAs and also called H2 blockers, are a class of medications that block the action of histamine at the histamine H2 receptors of the parietal cells in the stomach. This decreases the production of stomach acid. H2 antagonists can be used in the treatment of dyspepsia, peptic ulcers and gastroesophageal reflux disease. They have been surpassed by proton pump inhibitors (PPIs). The PPI omeprazole was found to be more effective at both healing and alleviating symptoms of ulcers and reflux oesophagitis than the H2 blockers ranitidine and cimetidine.
Pantoprazole, sold under the brand name Protonix, among others, is a proton pump inhibitor used for the treatment of stomach ulcers, short-term treatment of erosive esophagitis due to gastroesophageal reflux disease (GERD), maintenance of healing of erosive esophagitis, and pathological hypersecretory conditions including Zollinger–Ellison syndrome. It may also be used along with other medications to eliminate Helicobacter pylori. Effectiveness is similar to other proton pump inhibitors (PPIs). It is available by mouth and by injection into a vein.
Famotidine, sold under the brand name Pepcid among others, is a histamine H2 receptor antagonist medication that decreases stomach acid production. It is used to treat peptic ulcer disease, gastroesophageal reflux disease, and Zollinger-Ellison syndrome. It is taken by mouth or by injection into a vein. It begins working within an hour.
Esomeprazole, sold under the brand name Nexium [or Neksium] among others, is a medication which reduces stomach acid. It is used to treat gastroesophageal reflux disease, peptic ulcer disease, and Zollinger–Ellison syndrome. Its effectiveness is similar to that of other proton pump inhibitors (PPIs). It is taken by mouth or injection into a vein.
Rabeprazole, sold under the brand name Aciphex, among others, is a medication that decreases stomach acid. It is used to treat peptic ulcer disease, gastroesophageal reflux disease, and excess stomach acid production such as in Zollinger–Ellison syndrome. It may also be used in combination with other medications to treat Helicobacter pylori. Effectiveness is similar to other proton pump inhibitors (PPIs). It is taken by mouth.
Bismuth subsalicylate, sold generically as pink bismuth and under brand names including Pepto-Bismol, Pepti-Calm and BisBacter, is a medication used to treat temporary discomfort of the stomach and gastrointestinal tract, such as nausea, heartburn, indigestion, upset stomach, and diarrhea.
Achlorhydria and hypochlorhydria refer to states where the production of hydrochloric acid in gastric secretions of the stomach and other digestive organs is absent or low, respectively. It is associated with various other medical problems.
Alka-Seltzer is an effervescent antacid and pain reliever first marketed by the Dr. Miles Medicine Company of Elkhart, Indiana, United States. Alka-Seltzer contains three active ingredients: aspirin (ASA), sodium bicarbonate, and anhydrous citric acid. The aspirin is a pain reliever and anti-inflammatory, the sodium bicarbonate is an antacid, and the citric acid reacts with the sodium bicarbonate and water to form effervescence.
A gastrointestinal cocktail,, is a mixture of medications used to treat symptoms of dyspepsia. The GI cocktail generally contains a mixture of viscous lidocaine, an antacid, and an anticholinergic. The GI cocktail is commonly prescribed in the hospital or emergency department, and has been used to help distinguish chest pain as either gastrointestinal or cardiac. While it has been widely used in the treatment of dyspepsia, studies have suggested that the GI cocktail is only as effective as antacids alone.
Acid erosion is a type of tooth wear. It is defined as the irreversible loss of tooth structure due to chemical dissolution by acids not of bacterial origin. Dental erosion is the most common chronic condition of children ages 5–17, although it is only relatively recently that it has been recognised as a dental health problem. There is generally widespread ignorance of the damaging effects of acid erosion; this is particularly the case with erosion due to consumption of fruit juices because they tend to be considered as healthy. Acid erosion begins initially in the enamel, causing it to become thin, and can progress into dentin, giving the tooth a dull yellow appearance and leading to dentin hypersensitivity.
Maalox was a brand of antacid owned by Sanofi. Their main product is a flavored liquid containing a suspension of aluminum hydroxide and magnesium hydroxide, which act to neutralize or reduce stomach acid, for the purpose of relieving the symptoms of indigestion, heartburn, gastroesophageal reflux disease, and also stomach or duodenal ulcers. It also contains simethicone, an anti-foaming agent which helps eliminate bloating from gas. In large doses, the medicine can act as a laxative. The trademark is owned by Novartis International AG, and was first produced commercially in 1949.
An enteric coating is a polymer barrier applied to oral medication that prevents its dissolution or disintegration in the gastric environment. This helps by either protecting drugs from the acidity of the stomach, the stomach from the detrimental effects of the drug, or to release the drug after the stomach. Some drugs are unstable at the pH of gastric acid and need to be protected from degradation. Enteric coating is also an effective method to obtain drug targeting. Other drugs such as some anthelmintics may need to reach a high concentration in a specific part of the intestine. Enteric coating may also be used during studies as a research tool to determine drug absorption. Enteric-coated medications pertain to the "delayed action" dosage form category. Tablets, mini-tablets, pellets and granules are the most common enteric-coated dosage forms.
Effervescent or carbon tablets are tablets which are designed to dissolve in water and release carbon dioxide. The carbon dioxide is generated by a reaction of a compound containing bicarbonate, such as sodium bicarbonate or magnesium bicarbonate, with an acid such as citric acid or tartaric acid. Both compounds are present in the tablet in powder form and start reacting as soon as they dissolve in water.
Magnesium salts are available as a medication in a number of formulations. They are used to treat magnesium deficiency, low blood magnesium, eclampsia, and several other conditions. Magnesium is an essential nutrient.
Calcium supplements are salts of calcium used in a number of conditions. Supplementation is generally only required when there is not enough calcium in the diet. By mouth they are used to treat and prevent low blood calcium, osteoporosis, and rickets. By injection into a vein they are used for low blood calcium that is resulting in muscle spasms and for high blood potassium or magnesium toxicity.
Acid peptic diseases, such as peptic ulcers, Zollinger-Ellison syndrome, and gastroesophageal reflux disease, are caused by distinct but overlapping pathogenic mechanisms involving acid effects on mucosal defense. Acid reflux damages the esophageal mucosa and may also cause laryngeal tissue injury, leading to the development of pulmonary symptoms.
{{cite book}}: CS1 maint: location missing publisher (link)Last updated 1 January 2016
The dictionary definition of antacid at Wiktionary
Major chemical drug groups – based upon the Anatomical Therapeutic Chemical Classification System | |
|---|---|
| gastrointestinal tract / metabolism (A) | |
| blood and blood forming organs (B) | |
| cardiovascular system (C) | |
| skin (D) | |
| genitourinary system (G) | |
| endocrine system (H) | |
| infections and infestations (J, P, QI) | |
| malignant disease (L01–L02) | |
| immune disease (L03–L04) | |
| muscles, bones, and joints (M) | |
| brain and nervous system (N) |
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| respiratory system (R) | |
| sensory organs (S) | |
| other ATC (V) | |
