Cohort studyindependent cross-checkabstract checked★ key study I-PPI-117 in-depth review

No extra cancer with ranitidine

Ranitidine Use and Incident Cancer in a Multinational Cohort.

Overview

You SC et al.. JAMA Netw Open 2023 · PMID 37725377 · DOI 10.1001/jamanetworkopen.2023.33495

In 1.2 million people from 7 countries, ranitidine users developed cancer no more often than users of similar drugs.

Does the study support the specific claim? No · Methodological quality: high

Study explained simply

What did the researchers want to find out?: Check cancer risk after ranitidine.
How was the study done?: Multinational cohort.
How many people, animals or samples were studied?: 1,183,999 users.
What was actually found?: HR 1.04 (0.97-1.12).
How large was the observed effect?: 0.27 per 1000 PY difference.
What do the results mean in everyday life?: Past ranitidine use is unlikely to have caused cancer.
What are the study's limitations?: Limited follow-up.
What does it say about Elawady's specific claim?: Contradicts '320,000 ng in the stomach' implications.
Do the results apply to Germany and Europe?: Includes Europe.
What can explicitly not be concluded from this study?: Cannot exclude very long-term effects.

Authors: You SC et al.
Journal: JAMA Netw Open
Year: 2023
Identifier: PMID 37725377 DOI 10.1001/jamanetworkopen.2023.33495
Verification: verified – PubMed efetch 2026-10-26 + Crossref 2026-10-26
Retracted: no
Corrections: none
Extent checked: abstract only
Conflicts of interest and funding: Non-US government support; COI not in abstract

Is ranitidine associated with higher cancer risk than other H2RAs?

Study design: Cohort study – Multinational new-user active-comparator cohort network (OHDSI; 11 databases)
Population: Adults without prior cancer using H2RAs >30 days
Country: USA, UK, Germany, Spain, France, South Korea, Taiwan
Period: 1986-2020
Sample size: 1,183,999 (909,168 ranitidine; 274,831 other H2RA)
Inclusion and exclusion criteria: 1-year washout; no cancer history

Exposure / intervention: Ranitidine
Comparator: Famotidine, lafutidine, nizatidine, roxatidine
Endpoints: Any cancer (excluding non-melanoma skin); 16 subtypes; mortality
Statistical methods: Large-scale propensity matching, negative-control calibration, random-effects meta-analysis

Results: After matching: 15.92 vs 15.65 cancers per 1000 PY; calibrated HR 1.04 (0.97-1.12); no significant secondary outcome associations.
Absolute risks: Difference 0.27 per 1000 person-years (not significant)
Authors' conclusion: Ranitidine use was not associated with increased cancer risk compared with other H2RAs.

CI excludes >12% relative increase (stats/C-PPI-08_ranitidine.py).

If ranitidine formed huge NDMA amounts in the stomach, a cancer excess would be expected; none was found.

Long-latency cancers may need longer follow-up.

Includes European databases.

Strong evidence against clinically relevant in-vivo NDMA formation.

Multidimensional assessment
Multidimensional assessment
Authenticity of the source	verified
Methodological quality	high
Risk of bias	low
Precision of results	high
Directness	direct
Reproducibility	partly replicated
Consistency with the overall evidence	consistent
Regional transferability	high
Adequacy of the interpretation (by the archive)	not applicable

Very long-term effects.