Acid reducing medications


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Acid reducing medications

Medicine and surgery

Allergy and immunology

Antihistamines for allergies


Cardiology, cardiac surgery and vascular surgery

Coronary artery disease: Clinical (To be retired)

Heart failure: Clinical (To be retired)

Syncope: Clinical (To be retired)

Hypertension: Clinical (To be retired)

Hypercholesterolemia: Clinical (To be retired)

Peripheral vascular disease: Clinical (To be retired)

Leg ulcers: Clinical (To be retired)

Adrenergic antagonists: Alpha blockers

Adrenergic antagonists: Beta blockers

ACE inhibitors, ARBs and direct renin inhibitors

Thiazide and thiazide-like diuretics

Calcium channel blockers

Lipid-lowering medications: Statins

Lipid-lowering medications: Fibrates

Miscellaneous lipid-lowering medications

Antiplatelet medications

Dermatology and plastic surgery

Hypersensitivity skin reactions: Clinical (To be retired)

Eczematous rashes: Clinical (To be retired)

Papulosquamous skin disorders: Clinical (To be retired)

Alopecia: Clinical (To be retired)

Hypopigmentation skin disorders: Clinical (To be retired)

Benign hyperpigmented skin lesions: Clinical (To be retired)

Skin cancer: Clinical (To be retired)

Endocrinology and ENT (Otolaryngology)

Diabetes mellitus: Clinical (To be retired)

Hyperthyroidism: Clinical (To be retired)

Hypothyroidism and thyroiditis: Clinical (To be retired)

Dizziness and vertigo: Clinical (To be retired)

Hyperthyroidism medications

Hypothyroidism medications


Hypoglycemics: Insulin secretagogues

Miscellaneous hypoglycemics

Gastroenterology and general surgery

Gastroesophageal reflux disease (GERD): Clinical (To be retired)

Peptic ulcers and stomach cancer: Clinical (To be retired)

Diarrhea: Clinical (To be retired)

Malabsorption: Clinical (To be retired)

Colorectal cancer: Clinical (To be retired)

Diverticular disease: Clinical (To be retired)

Anal conditions: Clinical (To be retired)

Cirrhosis: Clinical (To be retired)

Breast cancer: Clinical (To be retired)

Laxatives and cathartics


Acid reducing medications

Hematology and oncology

Anemia: Clinical (To be retired)

Anticoagulants: Warfarin

Anticoagulants: Direct factor inhibitors

Antiplatelet medications

Infectious diseases

Pneumonia: Clinical (To be retired)

Urinary tract infections: Clinical (To be retired)

Skin and soft tissue infections: Clinical (To be retired)

Protein synthesis inhibitors: Aminoglycosides

Antimetabolites: Sulfonamides and trimethoprim

Miscellaneous cell wall synthesis inhibitors

Protein synthesis inhibitors: Tetracyclines

Cell wall synthesis inhibitors: Penicillins

Miscellaneous protein synthesis inhibitors

Cell wall synthesis inhibitors: Cephalosporins

DNA synthesis inhibitors: Metronidazole

DNA synthesis inhibitors: Fluoroquinolones

Herpesvirus medications



Miscellaneous antifungal medications

Anti-mite and louse medications

Nephrology and urology

Chronic kidney disease: Clinical (To be retired)

Kidney stones: Clinical (To be retired)

Urinary incontinence: Pathology review

ACE inhibitors, ARBs and direct renin inhibitors

PDE5 inhibitors

Adrenergic antagonists: Alpha blockers

Neurology and neurosurgery

Stroke: Clinical (To be retired)

Lower back pain: Clinical (To be retired)

Headaches: Clinical (To be retired)

Migraine medications

Pulmonology and thoracic surgery

Asthma: Clinical (To be retired)

Chronic obstructive pulmonary disease (COPD): Clinical (To be retired)

Lung cancer: Clinical (To be retired)

Antihistamines for allergies

Bronchodilators: Beta 2-agonists and muscarinic antagonists

Bronchodilators: Leukotriene antagonists and methylxanthines

Pulmonary corticosteroids and mast cell inhibitors

Rheumatology and orthopedic surgery

Joint pain: Clinical (To be retired)

Rheumatoid arthritis: Clinical (To be retired)

Lower back pain: Clinical (To be retired)

Anatomy clinical correlates: Clavicle and shoulder

Anatomy clinical correlates: Arm, elbow and forearm

Anatomy clinical correlates: Wrist and hand

Anatomy clinical correlates: Median, ulnar and radial nerves

Anatomy clinical correlates: Bones, joints and muscles of the back

Anatomy clinical correlates: Hip, gluteal region and thigh

Anatomy clinical correlates: Knee

Anatomy clinical correlates: Leg and ankle

Anatomy clinical correlates: Foot

Acetaminophen (Paracetamol)

Non-steroidal anti-inflammatory drugs


Opioid agonists, mixed agonist-antagonists and partial agonists

Antigout medications

Osteoporosis medications


Acid reducing medications


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High Yield Notes

8 pages


Acid reducing medications

of complete

External References

First Aid








Acid reflux

proton pump inhibitors for p. 408

Adverse effects/events

proton pump inhibitors p. 407

Clostridium difficile p. , 136

proton pump inhibitor use p. 407

Gastritis p. 388

proton pump inhibitors for p. 408

Peptic ulcer disease p. 389

proton pump inhibitors for p. 407

Proton pump inhibitors (PPIs) p. 407

acute interstitial nephritis p. 626

Beers criteria p. 248

gastrin and p. 380

for Helicobacter pylori p. , 144

naming convention for p. 255

Zollinger-Ellison syndrome p. 359

proton pump inhibitors for p. 408

External Links



Gil McIntire

Jake Ryan

Marisa Pedron

Samantha McBundy, MFA, CMI

Ursula Florjanczyk, MScBMC

Elizabeth Nixon-Shapiro, MSMI, CMI

Robyn Hughes, MScBMC

Acid reducing medications include antacids that directly lower the acidity of stomach contents, and antisecretory medications that act on parietal cells in the stomach to decrease acid secretion. They are used to treat conditions like gastroesophageal reflux disorder and peptic ulcer disease by decreasing the acidity of the stomach and allowing the epithelial linings to heal.

Now, the stomach is composed of four regions: the cardia, the fundus, the body, and the pyloric antrum. There’s also a pyloric sphincter, or valve, at the end of the stomach, which closes while eating, keeping food inside for the stomach to digest. The epithelial layer of the stomach contains different gastric glands which secrete a variety of substances.

Starting with the cardia, it contains mostly foveolar cells that secrete a protective mucus, which is mostly made up of water and glycoproteins. The fundus and the body contain both the parietal cells and enterochromaffin-like cells, and the antrum and pyloric areas contain G-cells. Now gastric acid is mainly composed of HCl, or hydrochloric acid, which is mainly secreted by the parietal cells. Parietal cells have M3, CCK2, and H2 membrane receptors, which modulate their secretory behavior. When food enters the stomach, it causes the stomach walls to expand, which leads to the activation of these receptors.

First, stomach expansion causes the branches of the vagus nerve that innervates the stomach to release acetylcholine, which activates M3 receptors. Next, the G cells in the antrum of the stomach release gastrin, which activate the CCK2 receptors. Gastrin and acetylcholine activate the enterochromaffin-like cells, which release histamine, that then activates H2 receptors.

Activation of M3, CCK2, and H2 receptors increases the conversion of H20 and CO2 to H+ and HCO3- by carbonic anhydrase. The H+ is then pumped out of the cell and into the stomach via the H+/K+-ATPase pump. These H+ ions combine with Cl- ions to form hydrochloric acid and decrease the pH in the stomach.

Normally, the stomach is protected from the acidic environment by the mucus secreted by foveolar cells. However, if there’s an imbalance between mucus and acid secretion, like in Zollinger-Ellison syndrome, which is caused by a gastrin secreting tumor, it could lead to damage of the stomach. This could manifest as chronic gastritis and gastric, or peptic ulcers. Now, in the esophagus, the lower esophageal sphincter prevents most of the gastric acid from coming back up when the stomach is full or when you’re laying down. If this sphincter is loose, the acid could reflux into the lower esophagus and erode the esophageal lining. This is called GERD, or gastroesophageal reflux disease, most commonly known as heartburn. One way to mitigate the harmful effects of gastrin in these disorders is to decrease its acidity through medications.


Acid-reducing medications are a type of drugs that work to reduce the amount of acid in a person's stomach. There are three main groups of acid-reducing medications. The most common type is called a proton pump inhibitor (PPI). This type of medication inhibits the enzyme called H, K-ATPase, which blocks gastric acid secretion by parietal cells of the stomach. PPIs include drugs like omeprazole, esomeprazole, and pantoprazole.

The second group consists of H2 receptor blockers. H2 receptor blockers work by blocking histamine H2 receptors located on parietal cells of the stomach. This in turn inhibits the release of gastric acid. Examples of H2 receptor blockers include cimetidine, famotidine, and nizatidine. The last group consists of antacids, which work by neutralizing stomach acid that's already been produced. Examples of antacids include magnesium trisilicate and aluminum hydroxide.


  1. "Katzung & Trevor's Pharmacology Examination and Board Review,12th Edition" McGraw-Hill Education / Medical (2018)
  2. "Goodman and Gilman's The Pharmacological Basis of Therapeutics, 13th Edition" McGraw-Hill Education / Medical (2017)
  3. "Rang and Dale's Pharmacology" Elsevier (2019)
  4. "Peptic ulcer disease" Am Fam Physician (2007)
  5. "Proton Pump Inhibitors, H2-Receptor Antagonists, Metformin, and Vitamin B-12 Deficiency: Clinical Implications" Advances in Nutrition (2018)
  6. "25 Years of Proton Pump Inhibitors: A Comprehensive Review" Gut and Liver (2017)

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