Ranitidine forms the carcinogen NDMA in the human stomach at levels thousands of times above safety limits (up to 320,000 ng per tablet).

Original statement

أكبر فضيحة سلامية كانت في 2019-2020 حين سُحب الرانيتيدين عالمياً بعد أن أظهرت تجارب براونستاين وآخرون (JAMA Open 2021) أنّ القرص الواحد يُولِّد NDMA المسرطنة تحت ظروف المعدة بمستويات تصل إلى 320 ألف نانوغرام — أعلى آلاف المرات من الحد المسموح.

not verbatim – paraphrase. Translation by the project; the Arabic wording is authoritative.

Translation

Ranitidine forms the carcinogen NDMA in the human stomach at levels thousands of times above safety limits (up to 320,000 ng per tablet).

Origin

Source status

Archive editors

Attribution

Archive editors (eltayebat.com); not verified as Elawady's own words

Origin

https://eltayebat.com/rule/acid-blockers/

Attribution uncertainty

Written by the archive operators; study selection is the archive's, not necessarily Elawady's.

Claimed mechanism

Nitrosation of ranitidine under acidic, nitrite-rich gastric conditions.

Claimed health effect

Cancer risk from NDMA.

Population concerned

Ranitidine users.

Geographic restriction by Elawady

none found

Scientific assessment

Mostly false – Essential parts of the statement are not supported by the evidence or are strongly exaggerated.

Certainty of evidence: moderate – Further research may still affect the assessment.

1. What was claimed?

A ranitidine tablet produces huge amounts of NDMA inside the stomach.

2. What is demonstrably correct?

Ranitidine (an H2 blocker, not a PPI) was withdrawn from the market in 2019–2020 because of NDMA contamination; Braunstein 2021 measured up to 320,000 ng NDMA from a 150 mg tablet in simulated gastric fluid with 50 mmol/L sodium nitrite (minimum 947 ng at 1 mmol/L).

3. What is wrong or exaggerated?

The archive presents a laboratory maximum under extreme nitrite conditions as what happens 'under the conditions of the stomach'. Under physiological nitrite no conversion was detected (I-PPI-118), the in-vivo FDA RCT did not find increased NDMA excretion (I-PPI-07), and no cancer excess was seen in 1.18 million users (I-PPI-117). Four of the seven Braunstein authors were affiliated with Valisure LLC, the laboratory that had filed the citizen petition to the FDA.

4. What remains unclear?

Very long-term cancer risk after ranitidine has not been fully settled, but the largest cohort found no excess; product impurity levels (which rose with storage) are a separate issue from formation in the stomach.

5. Which studies support it?

A-PPI-18 (in vitro).

6. Which studies contradict it?

Florian 2021 (I-PPI-07): median paired difference in urinary NDMA 0 ng (P=.54) and -1.1 ng (P=.71). Gao 2021 (I-PPI-118): only background NDMA (21-24 ng) up to 5000 umol/L nitrite. You 2023 (I-PPI-117): cancer HR 1.04 (0.97-1.12) vs other H2RAs.

7. What applies to Germany and Europe?

Ranitidine is no longer marketed in the EU/Germany; this claim has no relevance for current PPIs such as pantoprazole or omeprazole.

8. What is known about Egypt?

Ranitidine products were also withdrawn in many countries after 2020; status in Egypt was not verified.

9. What practical conclusion is appropriate?

The ranitidine story concerns one H2-blocker and a contamination/stability problem; it cannot be transferred to PPIs.

Assessment details

Rationale for certainty of evidence

The 320,000 ng figure comes from simulated gastric fluid with 50 mmol/L nitrite, about 500 times the upper physiological gastric nitrite (A-PPI-18). An FDA laboratory study found no NDMA formation at physiological nitrite and formation only at >=50-fold physiological levels (I-PPI-118); a double-blind crossover RCT found no increase in urinary NDMA after ranitidine (I-PPI-07); and a multinational active-comparator cohort of 1.18 million people found no cancer excess with ranitidine versus other H2 blockers (HR 1.04, 0.97-1.12; I-PPI-117). The 2019-2020 recall because of NDMA impurities in products did happen.

Source quality

In-vitro research letter (four of seven authors affiliated with the laboratory that petitioned the FDA) versus a small but direct human RCT.

Regional transferability

High.

Individual exceptions

Effects in people with unusually high gastric nitrite cannot be excluded.

Regional scope of the claim

general (biological/medical)

Last reviewed

26 October 2026 provisional

Scientific evidence in detail

Scientifically refuted – High-quality evidence shows the opposite, or the claim contradicts well-established physiology.

Research question: Does ranitidine form NDMA in the human stomach at levels thousands of times above safety limits (up to 320,000 ng per tablet)?

Study results as reported by the authors. Our assessment follows below.

Open questions

Very long-term cancer follow-up.

How deeply was this checked?

4 linked studies: 1 checked in full text (0 of them with a structured risk-of-bias assessment), 3 on the basis of the abstract, 0 bibliographically only. No formal assessment with two independent reviewers and no independent human expert review has taken place yet.

Last scientific review: 26 October 2026

In plain language

Ranitidine, an older acid medicine, was taken off the market because some products contained the contaminant NDMA. A laboratory study found very high NDMA formation, but only with nitrite levels about 500 times higher than normal in the stomach. Tests at normal stomach conditions, a trial in people and a study of more than one million users found no sign of relevant NDMA formation or extra cancer. Modern PPIs are different drugs.

Studies on this claim

Regional context

Germany / EU

Ranitidine is no longer marketed in the EU/Germany; this claim has no relevance for current PPIs such as pantoprazole or omeprazole.

Egypt

Ranitidine products were also withdrawn in many countries after 2020; status in Egypt was not verified.

• Food-safety governance and official controls
• Pesticide residues in fruit and vegetables on the EU/German market (incl. imports from Egypt)
• Pesticide residues in produce sold on the Egyptian domestic market
• Antibiotic (veterinary drug) residues in poultry meat and eggs
• Antimicrobial use in food animals and antibiotic growth promoters
• Hormones in poultry, meat, milk and farmed fish
• Dioxins, PCBs and PFAS in eggs and other animal foods
• Aflatoxin M1 in milk and dairy products
• Aflatoxins in groundnuts (peanuts)
• Heavy metals in fish
• Farmed fish (aquaculture): drugs, water source and controls
• Import controls and the meaning of RASFF notifications for Egyptian products

What applies in my country?

General scientific assessment

Mostly false Mostly false: the recall was real, but the '320,000 ng in the stomach' figure comes from extreme laboratory conditions and was not found under realistic conditions or in people.

The following areas of food safety are relevant to this statement:

• Pesticides and pesticide residues
• Veterinary medicines and antibiotics
• Hormonal growth promoters
• Contaminants (heavy metals, PFAS, PCBs, dioxins, nitrate)

Eggs · Poultry · Dairy · Fish and seafood · Red meat · Fruit and vegetables

Limits: legal rules describe what is allowed, not what every single food contains. Measurement data come from samples and are meaningful only together with their method details.

Country of residence or purchase Compare with another country

References

1. Analysis of Ranitidine-Associated N-Nitrosodimethylamine Production Under Simulated Physiologic Conditions.. Braunstein LZ et al.. JAMA Netw Open 2021 · PMID 33512515 · DOI 10.1001/jamanetworkopen.2020.34766
2. Effect of Oral Ranitidine on Urinary Excretion of N-Nitrosodimethylamine (NDMA): A Randomized Clinical Trial.. Florian J et al.. JAMA 2021 · PMID 34180947 · DOI 10.1001/jama.2021.9199
3. Ranitidine Use and Incident Cancer in a Multinational Cohort.. You SC et al.. JAMA Netw Open 2023 · PMID 37725377 · DOI 10.1001/jamanetworkopen.2023.33495
4. In Vitro Analysis of N-Nitrosodimethylamine (NDMA) Formation From Ranitidine Under Simulated Gastrointestinal Conditions.. Gao Z et al.. JAMA Netw Open 2021 · PMID 34181009 · DOI 10.1001/jamanetworkopen.2021.18253