Famotidine Dosage for Gastritis

For gastritis treatment, the recommended dosage of Famotidine (Pepcid) is 20 mg twice daily for up to 6 weeks. 1

Dosing Recommendations

Famotidine 20 mg should be taken twice daily, typically in the morning and before bedtime, for the treatment of gastritis 1
The medication can be taken with or without food, and may be given with antacids if needed 1
Treatment duration for symptomatic gastritis is typically up to 6 weeks, though this may vary based on symptom response 1, 2

Famotidine has demonstrated effectiveness in relieving abdominal symptoms and improving quality of life in patients with chronic symptomatic gastritis 2
Studies show that famotidine at 20 mg/day for 4 weeks significantly attenuates common gastritis symptoms including epigastralgia, epigastric fullness, and heartburn 2
Famotidine works by inhibiting the histamine-2 receptor on gastric parietal cells, thereby decreasing gastric acid secretion 3

For patients with moderate renal impairment (creatinine clearance 30-60 mL/min), the dosage should be reduced to 20 mg once daily 1
For severe renal impairment (creatinine clearance <30 mL/min), the recommended dosage is 20 mg every other day 1
Standard adult dosing can be used for pediatric patients weighing 40 kg or more; alternative formulations should be used for those weighing less 1

Recent studies show that famotidine 20 mg provides acid suppression for approximately 6 hours, with the percentage of time gastric pH is maintained above 4 being around 24% over a 24-hour period 4
This is less than the acid suppression provided by proton pump inhibitors (PPIs) such as esomeprazole, which maintains pH above 4 for approximately 35-54% of the time depending on dosage 4
However, famotidine may be preferred in some cases due to its rapid onset of action and different side effect profile compared to PPIs 3

Tachyphylaxis (decreased response) can develop within 6 weeks of starting famotidine treatment, which may limit its effectiveness for long-term use 3
After discontinuation of famotidine, endoscopic relapse rates of gastritis can be as high as 57% within 3 months 5
For patients with severe or persistent symptoms despite famotidine treatment, consider:
- Evaluating for H. pylori infection, which may require specific eradication therapy 3
- Switching to a PPI if symptoms persist, as PPIs have been shown to be more effective than H2RAs for acid suppression 3, 4
- Performing endoscopy if symptoms do not respond to twice-daily acid suppression therapy 3

Assess symptom response after 2-4 weeks of treatment 2
If symptoms persist despite 4-6 weeks of appropriate therapy, further diagnostic evaluation should be considered 3
For patients requiring long-term acid suppression, be aware that famotidine appears to have less impact on corpus gastritis compared to PPIs in patients with H. pylori infection 6