No, aluminium-magnesium antacids should not be used instead of PPIs for gastric protection in patients taking NSAIDs.
PPIs are the evidence-based standard for gastroprotection in NSAID users and should be prescribed instead of antacids, which have not proven efficacy for preventing NSAID-induced ulcers or complications. 1, 2
Why PPIs Are Superior
The 2004 guideline on appropriate NSAID use explicitly states that histamine-2-receptor antagonists and antacid drugs have not proved their efficacy for gastroprotection during NSAID therapy 1. While antacids may provide symptomatic relief from dyspepsia, they do not prevent the serious complications that matter most: ulcers, bleeding, perforation, and obstruction.
The most recent high-quality evidence from a 2025 Cochrane systematic review demonstrates that:
- PPIs probably result in a 71% reduction in incident ulcers compared to placebo (RR 0.29,95% CI 0.23-0.36; moderate-certainty evidence) 2
- PPIs may reduce ulcer complications (RR 0.33,95% CI 0.10-1.07; low-certainty evidence) 2
- PPIs probably result in slight improvement in quality of life 2
Clinical Algorithm for Gastroprotection
High-risk patients requiring PPIs include those with:
- History of peptic ulcer or GI bleeding 3, 1
- Age ≥65 years 1, 4
- Concurrent use of anticoagulants (warfarin) 1
- Concurrent corticosteroid therapy 1
- Concurrent low-dose aspirin 3, 1
- Multiple risk factors (risk increases cumulatively) 3
For these high-risk patients, PPI co-therapy is necessary regardless of whether they use traditional NSAIDs or COX-2 selective inhibitors 4.
Why Not Antacids?
Antacids (including aluminium-magnesium combinations) work by neutralizing existing gastric acid but:
- Provide only temporary symptomatic relief
- Do not prevent ulcer formation
- Have no proven efficacy in preventing serious GI complications 1
- Are not included in evidence-based guidelines for NSAID gastroprotection 1, 4
A 2004 drug-utilization study found that antacids were being prescribed for gastroprotection despite lack of evidence, identifying this as "a possible problem where an intervention could be appropriate" 5.
Important Caveats
While PPIs are effective, recent guidelines emphasize PPI stewardship 6, 7:
- Use PPIs only for appropriate indications and duration
- Periodically reassess the need for continued therapy
- Be aware of potential long-term adverse effects (fractures, micronutrient deficiencies, Clostridioides difficile infection) 8, 7
However, in patients with genuine risk factors for NSAID-induced GI complications, the benefits of PPI gastroprotection clearly outweigh these risks 3, 4.
Bottom Line
Antacids are not an acceptable substitute for PPIs in NSAID gastroprotection. If a patient requires gastroprotection due to NSAID use and has identifiable risk factors, prescribe a PPI. If the patient is low-risk (young, no risk factors), routine gastroprotection with either PPIs or antacids is not recommended 3.