Aspirin, acetaminophen may hurt flu vaccines

William Atkins
Wednesday, 02 December 2009 18:37

Science - Health

According to research by the University of Missouri, vaccines such as those for the H1N1 flu virus (Influenza A  virus) may not be as effective if over-the-counter drugs, such as aspirin and Tylenol, are taken regularly.



The December 1, 2009 press release “Aspirin, Tylenol May Decrease Effectiveness of Vaccines ” from the University of Missouri News Bureau states that specific enzymes in the body (associated with the vaccines) could be blocked from the regular use of aspirin and Tyulenol.

Such action could inhibit the effectiveness of flu vaccines and other vaccines.

Charles R. Brown, who is an associate professor of veterninary pathobiology at the University of Missouri at Columbia, stated, “If you’re taking aspirin regularly, which many people do for cardiovascular treatment, or acetaminophen (Tylenol) for pain and fever and get a flu shot, there is a good chance that you won’t have a good antibody response.”

Dr. Brown, who is one of the authors of the study, adds, “These drugs block the enzyme COX-1, which works in tissues throughout the body."

He also states, "We have found that if you block COX-1, you might be decreasing the amount of antibodies your body is producing, and you need high amounts of antibodies to be protected.”

The conclusions of Dr. Brown, along with Victoria A. Blaho, Matthew W. Buczynski, and Edward A. Dennis, appear in the article “Cyclooxygenase-1 Orchestrates Germinal Center Formation and Antibody Class-Switch via Regulation of IL-17.”

It appears in the November 2009 issue of The Journal of Immunology (2009, 183, 5644-5653; doi: 10.4049/jimmunol.0901499).