Nørgaard M, Andersen IT, Heide-Jørgensen U, et al. - Use of ranitidine was not associated with a substantial increase in bladder or kidney cancer occurrence.

• Withdrawal of ranitidine in 2019 was because of high levels of N-nitrosodimethylamine, a probable human carcinogen.

• This is a Danish nationwide cohort study including 31,393 initiators (adults 18 years or older) of ranitidine, 65,384 initiating other H2-blockers (H2-receptor antagonists), and 509,849 initiating proton pump inhibitors (PPI), to clarify risk of bladder and kidney cancer in ranitidine users.

• Experts employed propensity scores for ranitidine use to calculate stabilized inverse probability of treatment (sIPT) weights as well as applied Cox regression to estimate crude and weighted HRs.

• Relative to other H2-blockers, the crude HR for bladder cancer was estimated to be 1.33, but sIPT weighting attenuated this to 1.11.

• The estimated weighted HR was 1.24 (95% CI: 1.04–1.48) vs PPI initiators.

• The weighted HR for kidney cancer was 0.89 (95% CI: 0.72–1.10) vs users of H2-blockers and 0.87 (95% CI: 0.67–1.13) vs users of PPI.