Department of Research & Evaluation News

New Kaiser Permanente research shows that the COVID-19 vaccine does not increase the risk of developing tinnitus, which is a ringing in the ears.

“Early on in the COVID-19 pandemic, some people complained about hearing some sound after being vaccinated, but it wasn’t actually an external sound, it was tinnitus, which is the perception of sound — often described as a ringing or buzzing in the ears,” said the study’s lead author, Stanley Xu, PhD, a senior research scientist with the Kaiser Permanente Southern California Department of Research & Evaluation. “So, we wanted to do an analysis to determine if there was a link between tinnitus and the COVID-19 vaccine.”

An earlier study also found no link between tinnitus and the COVID-19 vaccine, but it included only vaccinated people. In this Kaiser Permanente study, researchers looked at electronic health records of nearly 14,000 people who experienced tinnitus from inpatient, emergency department, and outpatient settings between September 2023 and March 2024.

Analysis accounted for seasonal variation

The analysis focused on people ages 12 years and older who did and didn’t receive the COVID-19 XBB.1.5 vaccines, which were the most current at that time. Researchers included unvaccinated individuals in the study to account for trends in tinnitus, such as seasonal variation, and improve the accuracy of their statistics. The study also involved participants who received both the flu vaccine and the COVID-19 vaccine at the same time.

“We found no sign that the current vaccines caused more cases of tinnitus in the 14 and 28 days after vaccination,” Dr. Xu said. “This was true both in the overall group and in subgroups like different age ranges and people who got the flu shot at the same time as the COVID-19 vaccination.”

The study was published in July 2025 in Vaccine.

Study provides reassurance about safety

Researchers said the study gives physicians and health care providers solid evidence to reassure patients that the updated COVID-19 vaccine is safe when it comes to the risk of developing tinnitus.

“We will continue to watch for any new safety concerns in order to keep the public informed of potential COVID-19 vaccine safety issues,” Dr. Xu said.

In addition to Dr. Xu, other researchers who worked on the study included Lina S. Sy, MPH; Vennis Hong, MPH; Lei Qian, PhD; Kimberly J. Holmquist, MPH; Katia J. Bruxvoort, PhD; Bing Han, PhD; Bruno Lewin, MD, of the Department of Research & Evaluation. Dr. Xu and Dr. Lewin also are affiliated with the Kaiser Permanente Bernard J. Tyson School of Medicine. Dr. Bruxvoort also is an assistant professor at the University of Alabama.