The study’s subjects were asked to report the frequency of painkiller use, but not the number of tablets taken per day or dosage, another potential variable, according to the study.

The researchers currently do not have information on how long the medications have to be used before the risk of hypertension increases.

Ibuprofen and other nonsteroidal anti-inflammatories may cause hypertension by inhibiting the production of prostaglandins, substances that improve blood flow, and by increasing sodium retention, the study said.

The link between ibuprofen and hypertension is a well-established one, said Randall M. Zusman, director of the division of hypertension and vascular medicine at Massachusetts General Hospital and a HMS associate professor of medicine.

“I strongly advise my patients not to take [ibuprofen] chronically,” said Zusman, who had not seen the report. “Any patient with high blood pressure should be vigilant about taking anti- inflammatories. In general, no one should take drugs they don’t need.”

Acetaminophen may also inhibit prostaglandin production, according to the study. No definite conclusion explaining the drug’s effect on blood pressure was reached.

“There’s no scientific mechanism by which acetaminophen can cause increased blood pressure,” said Gutsche.

Given the ready availability of the painkillers studied, possible associations with hypertension merit further study, the researchers said.

The study’s results “definitely need to be replicated by other independent groups,” said Curhan.

“It’s not a matter to be alarmed over,” but is something to be aware of, said Meir J. Stampfer, an HSPH professor of epidemiology and nutrition and one of the study’s authors.

“We’ll be exploring other populations to get a better handle on this,” he said.