Liver abnormalities (increased bilirubin and liver weight) occurred in mice, rats and monkeys at doses (respectively) 0.5, 1, and 3 times the recommended human daily dose based on body surface area comparisons. Testicular atrophy occurred in baboons at doses 2 times the recommended human dose based on body surface area comparisons, and in rats at doses 6 times the recommended human daily dose based on body surface area comparisons.
Chat online with Pfizer Medical Information regarding your inquiry on a Pfizer medicine.
*Contact Medical Information. 8AM-9PM ET Monday to Friday; excluding holidays.
Submit a medical question for Pfizer prescription products.
To report an adverse event related to the Pfizer-BioNTech COVID-19 Vaccine, and you are
not part of a clinical trial* for this product, click the link below to submit your
*If you are involved in a clinical trial for this product, adverse
events should be reported to your coordinating study site.
If you cannot use the above website, or would like to report an adverse event related
to a different Pfizer product, please call Pfizer Safety at
You may also contact the U.S. Food and Drug Administration (FDA) directly to report
adverse events or product quality concerns either online at