Acute Gastritis Medication

Updated: Feb 03, 2023
  • Author: Sarah El-Nakeep, MD; Chief Editor: BS Anand, MD  more...

Medication Summary

Specific treatment of gastritis is dependent on the underlying etiology.

According to the Centers for Disease Control and Prevention (CDC), the treatment of tuberculosis consists of a 2-month course of daily isoniazid, rifampin, and pyrazinamide, followed by 4-7 months of daily isoniazid along with rifampin. [42] See Tuberculosis.

Medical management (antibiotics, supportive care) is generally ineffective in treating phlegmonous gastritis; surgical intervention is typically required.

Several drugs are available for the treatment of cytomegalovirus (CMV) infection. These include ganciclovir, valganciclovir, foscarnet, and cidofovir. It should be noted that the majority of immunocompetent individuals recover from CMV infection without any therapeutic intervention. See Cytomegalovirus.

The treatment of C albicans includes a variety of agents, including nystatin, oral clotrimazole, itraconazole, fluconazole, amphotericin B, and ketoconazole. See Candidiasis.

The treatment of disseminated histoplasmosis includes several effective agents, including amphotericin B, itraconazole, and fluconazole. See Histoplasmosis.

No drugs are available to treat anisakidosis. Endoscopic removal may be necessary.



Class Summary

Used for general prophylaxis. Antacids containing aluminum and magnesium can help relieve symptoms of gastritis by neutralizing gastric acids. These agents are inexpensive and safe.

Aluminum and magnesium hydroxide, magnesia and alumina oral suspension (Rulox)

Drug combination that neutralizes gastric acidity and increases pH of the stomach and duodenal bulb. Aluminum ions inhibit smooth-muscle contraction and inhibit gastric emptying. Magnesium/aluminum antacid mixtures are used to avoid bowel function changes.


H2 blockers

Class Summary

This class includes drugs whose mechanism of action is competitive inhibition of histamine at the histamine 2 (H2) receptor. Histamine plays an important role in gastric acid secretion, thereby making H2 blockers effective suppressors of basal gastric acid output and acid output stimulated by food and the neurological system. There are different drugs with different potencies and half-lives (eg, cimetidine, ranitidine, famotidine, nizatidine). Cimetidine will be discussed below as a representative of this class of drugs.

Cimetidine (Tagamet)

Inhibits histamine at H2 receptors of gastric parietal cells, which results in reduced gastric acid secretion, gastric volume, and hydrogen concentration.


Proton pump inhibitors

Class Summary

Proton pump inhibitors are potent inhibitors of the proton (acid) pump (ie, the enzyme H+,K+-ATPase), located in the apical secretory membrane of the gastric acid secretory cells (parietal cell). Proton pump inhibitors can completely inhibit acid secretion and have a long duration of action. They are the most effective gastric acid blockers. Omeprazole will be discussed as a representative of this class of drugs.

Omeprazole (Prilosec)

Decreases gastric acid secretion by inhibiting the parietal cell H+/K+-ATPase pump.



Class Summary

Bacterial infections also can cause gastritis. The most common causative organism is H pylori. A number of therapeutic regimens are effective against H pylori. Single antimicrobial agents generally are not recommended because of the potential development of resistance.

Dual therapy includes a proton pump inhibitor plus amoxicillin (no longer recommended because eradication rates are only 30-80%) or a proton pump inhibitor plus clarithromycin (eradication rate of roughly 71%). Adding a second antimicrobial agent is recommended for successful eradication.

Triple regimens are preferred in clinical practice. One drug is a proton pump inhibitor or a bismuth-based drug, the second drug is clarithromycin, and the third drug is amoxicillin or metronidazole. Quadruple therapy regimens (ie, 2 antibiotics, bismuth, antisecretory agent) generally are effective; however, because more drugs are prescribed and taken, increased adverse effects and decreased patient compliance can occur. This regimen is used in the event that triple therapy fails.

The decision as to which medications to use is based on the following 4 criteria: (1) the different toxicities of the various medications, (2) the relative costs of each medication and regimen, (3) the emergence of antimicrobial-resistant bacteria, and (4) the level of patient compliance.

Amoxicillin (Amoxil, Trimox)

Interferes with the synthesis of cell wall mucopeptides during active multiplication, resulting in bactericidal activity against susceptible bacteria.

Tetracycline (Sumycin)

Inhibits bacterial protein synthesis by binding with 30S and possibly 50S ribosomal subunit(s).

Metronidazole (Flagyl)

Imidazole ring-based antibiotic active against various anaerobic bacteria and protozoa.

Clarithromycin (Biaxin)

Inhibits bacterial growth, possibly by blocking the dissociation of peptidyl t-RNA from ribosomes and causing arrest of RNA-dependent protein synthesis.


Antitubercular Agents

Rifabutin (Mycobutin)

Mycobutin is a drug that is used off label to treat tuberculosis. It inhibits DNA-dependent RNA polymerase and is metabolized by hepatic CYP3A4 to active and inactive metabolites.


Antidiarrheal agents

Class Summary

Used in combination with antibiotics and proton pump inhibitors/H2 receptor antagonists to eradicate H pylori.

Bismuth subsalicylate (Bismatrol, Pepto-Bismol)

Drug combination that treats active duodenal ulcer associated with H pylori.


Antiparasitic Agents

Nitazoxanide (Alinia)

Nitazoxanide is an antiparasitic agent. It inhibits the growth of sporozoites and oocysts of Cryptosporidium and trophozoites of Giardia, as well as interferes with pyruvate:ferredoxin oxidoreductase (PFOR), essential to anaerobic energy metabolism.

It is metabolized by hydrolysis and glucuronidation, and excreted in the urine, bile, and feces.

Tinidazole (Tindamax)

Tinidazole is an antiprotozoal; it may cause cytotoxicity by damaging DNA and preventing further DNA synthesis.

This drug undergoes oxidation, hydroxylation, and conjugation, and is excreted mainly in the urine and feces.


H pylori Agents

Bismuth subsalicylate (Kaopectate, Kaopectate Extra Strength, Maalox Total Relief)

This agent has antimicrobial anti-inflammatory action (bismuth) and an antisecretory effect (salicylate).

Bismuth subsalicylate is hydrolyzed in stomach to form slightly soluble bismuth oxychloride (BiOCl) and salicylic acid. Bismuth is excreted through the feces, and salicylate is excreted through the urine.


Hippuric Acids


Potassium-Competitive Acid Blockers


A relatively new group of reversible proton-pump inhibitors known as potassium-competitive acid blockers (PCAB) was first approved in Japan in 2015. In May 2022, the FDA approved vonoprazan (the first in the PCAB class) for the treatment of H pylori as a part of triple therapy. There are two combination packs available: vonaprazon + amoxicillin) and vonoprazan + amoxicillin + clarithromycin.