After my recent post on Omeprazole’s alternative drugs, I want to stay on the subject of gastro-oesophageal reflux disease (GORD) and its treatment.
How The Mechanism Of Action Differs Between Ranitidine & Omeprazole?
Ranitidine and Omeprazole belong to different classes of drugs, both used in the treatment of heartburn/indigestion. Ranitidine is classified as an h2 receptor antagonist, commonly named h2 blockers. Omeprazole belongs to a group of drugs called proton pump inhibitors (PPIs).
The differences between both drugs come from a distinct mechanism of action on stomach acid suppression. Stomach acid is produced in response to the activation of one of three receptors located on cells in the lining of the stomach. One type of these receptors (h2 receptors) can be blocked by Ranitidine, preventing the initial production of the acid via this one route.
PPIs such as Omeprazole, on the other hand, block the proton pump, which is responsible for the secretion of the stomach acid in the final part of its production.
Watch the video below to get a more detailed explanation of the mechanism of action of both drugs.
Ranitidine vs Omeprazole: The Effectiveness
A number of studies and clinical trials confirmed that PPIs (Omeprazole) is more effective in the reduction of acid production than H2-blockers (Ranitidine). PPIs are more effective in the reduction of acid production because acid secretion is stopped in the last stage of acid production.
Ranitidine vs Omeprazole: Safety And Common Side Effects
Ranitidine common side effects
Ranitidine has a very good side effect profile with no common (1 in 10) side effects listed.
Omeprazole common side effects
The use of Omeprazole is associated with a number of common side effects, including:
- Abdominal pain
Long term use of Omeprazole (or other PPIs) may increase (BNF,n.d):
Risk of bone fractures (high doses are taken mainly by the elderly population)
Risk of gastrointestinal infections
In 2019 number of Ranitidine products were recalled from UK pharmacies and supermarkets due to possible contamination with N-Nitrosodimethylamine (NDMA), a probable human carcinogen. Recalled products included over-the-counter and prescription-only Ranitidine. You can read more about it in my separate post: Ranitidine and Cancer: What is the risk?
In 2017 a research paper was published in Gut magazine associating the use of PPIs with increased risk of gastric cancer development. This study looked at patients from Hong Kong who were treated for Helicobacter pylori infection.
H. pylori infection can cause recurring episodes of indigestion. Treatment of confirmed H. pylori infection involves taking a short course of 2 different antibiotics with a PPI, such as Omeprazole (triple therapy).
Although eradication of H. pylori infection reduces the risk of stomach cancer development, the above study found that taking PPIs more than doubled this risk. The average time that PPIs were taken by patients was three years after the triple therapy.
All patients had a long history of gastritis, which is the inflammation of the stomach lining (BMJ, n.d.). This risk is further increased with the duration of treatment and dose frequency after the triple therapy.
The same study concluded that taking H2 blockers, such as Ranitidine, is not associated with an increased risk of stomach cancer development.
Use Of Ranitidine & Omeprazole At The Same Time
The NICE guideline recommends the use of H2-blocker (Ranitidine) at night in addition to PPIs (Omeprazole) for people with persistent or recurrent symptoms of GORD or confirmed oesophagitis (inflammation of the tube that connects the stomach with your mouth).
This should be prescribed on a short-term basis (for example, for a 2-week course intermittently).) and when patients experience symptoms at night, subject to clinical judgment by a GP (NICE, 2017).
NICE suggests additional use of H2 blockers such as Ranitidine is likely to be increasingly ineffective, patients may not benefit from combination treatment, and within weeks night-time symptoms may come back (ibid).
Can You Take Ranitidine And Omeprazole Together?
Based on clinical judgment, the GP may decide to prescribe both Ranitidine and Omeprazole. Pharmacologically, Omeprazole overlaps the mechanism of action of Ranitidine.
Based on this and as it is suggested by the NICE guidelines addition of Ranitidine in the treatment of persistent GORD together with Omeprazole may bring short benefits, if any.
Other strategies on the management of GORD need to be explored, including doubling up the dose or switching from daily to twice-daily dosing, or switching to a different PPI.
Current evidence on the use of these strategies, however, is limited.
To sum up, Omeprazole is more effective in controlling stomach acid production and the management of GORD symptoms than Ranitidine. PPIs are associated with some common side effects; long-term use of PPIs may increase the risk of infections and bone fractures.
In contrast, H2 blockers have a better safety profile; however, they are less effective in reducing stomach acid production.