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If you're like millions of other Americans, you normally don't hesitate to pop a Tylenol or Advil to relieve a nagging headache.
In the wake of new research linking the popular over-the-counter pain relievers acetaminophen, best known as Tylenol, and ibuprofen, often sold as Advil, to high blood pressure, you may think twice.
Should you take the medications? Are Tylenol and Advil safe?
Ibuprofen has been linked to a rise in blood pressure, but acetaminophen has long been considered relatively free of side effects if taken as directed.
The study conducted by researchers at Brigham and Women's Hospital suggested that the pain reliever may be riskier than previously believed. High doses of acetaminophen have been associated with liver and kidney damage, but the new study found double the risk of hypertension among women who took the equivalent of one Tylenol extra-strength pill daily compared to women who didn't take the pills.
The study has raised new concerns about the use of popular over-the-counter painkillers.
The researchers at Brigham and Women's Hospital even speculated that regular use of drugs like Tylenol and Advil could be a contributing factor to the growing prevalence of hypertension in the United States.
Acetaminophen, ibuprofen and aspirin have long been the pills of choice for headache sufferers, weekend warriors with muscle aches, and people coping with chronic pain caused by conditions like arthritis. But the pills are intended for short-term use at low doses.
"Taking a couple of Tylenol for headaches is different from someone who takes it every day," says Dr. Christie Ballantyne, a cardiologist at Houston's Methodist DeBakey Heart Center. "If you're using them at higher dosages for prolonged periods of time, it's important to share the information with your physician."
While some doctors express doubts about the evidence in the study — it was based on questionnaires, not a randomized clinical trial — they nevertheless are recommending a new level of caution for people who take the painkillers regularly.
Uncontrolled high blood pressure can lead to heart attacks and stroke.
"We used to think acetaminophen was pretty safe," says Dr. Franz Messerli, director of the hypertension program as St. Luke's Roosevelt Medical Center, New York. "This study teaches us otherwise."
Researchers examined 5,123 women ages 34 to 77 who had participated in the massive Nurses' Health Study , which has followed the health of more than 120,000 female nurses since 1976.
None of the women had high blood pressure when the study began.
The researchers found that older women who took the highest doses — 500 mg of acetaminophen every day or the equivalent an of an extra-strength Tylenol — had a 93 percent increased risk of developing hypertension compared to non-users. Younger women had a two-fold elevated risk.
The women were taking pain relievers for various reasons, including headache, backache, muscle or joint pain or menstrual cramps, the researchers reported.
Even lower doses of acetaminophen may have been associated with high blood pressure if the study had lasted longer, lead author Dr. John Forman of Harvard Medical School said in an e-mail.
Older women who took more than 400 mg a day of ibuprofen — equal to about two Advil — had a 78 percent increased risk of developing high blood pressure compared to those who didn’t take the drug.
Aspirin was not associated with high blood pressure.
A spokeswoman for McNeil Consumer & Specialty Pharmaceuticals, which manufactures Tylenol, counters that because the study was based on questionnaires of past behavior rather than rigorous clinical testing, it did not establish a definitive relationship between acetaminophen use and hypertension.
"We would always advise consumers to contact their physician if they have concerns about interactions with medications, says spokeswoman Kathy Fallon.
Dr. Daniel Jones, vice chancellor and dean of the School of Medicine, University of Mississippi Medical Center in Jackson, who had no role in the study, agrees that the evidence isn't strong enough to conclude that the painkillers cause hypertension.
"There is no definitive answer," he says.
Women with a low risk for cardiovascular disease who suffer from osteoarthritis shouldn't stop taking acetaminophen or ibuprofen based on the study, says Jones. Yet for those with mild pain and high heart risk, "I would recommend that she not use the analgesics for pain on a regular basis."
But for short-term use, the benefits likely outweigh the risks.
"When I get a headache tonight, am I going to take a Tylenol? Absolutely," says Jones.
Dr. Suman Wason, senior director of global medical affairs at Wyeth Consumer Healthcare, which makes Advil, notes that all nonsteroidal anti-inflammatory drugs, including ibuprofen, can increase blood pressure "a few millimeters per person," but the elevation goes away when the medication is stopped.
The label on Advil recommends that an individual take no more than 1,200 mg a day for not more than 10 days.
"If you follow the label on Advil and take as directed, you will not have problems," says Wasson.
What about men and children?
The study looked at women, but what about men or very young children who are often given acetaminophen or ibuprofen for fever or teething pain?
In prior studies, ibuprofen and other NSAIDs have been associated with hypertension in both men and women, but the effects of acetaminophen have not yet been studied in men, says Forman.
Messerli, who was not associated with the study, believes the effects could be similar in men. "If there is indeed a real association between Tylenol and high blood pressure, it's probably the same in men as in women."
At the same time, children whose cardiovascular systems are typically healthier than older adults wouldn't likely be harmed by an elevation in blood pressure, he says. Most at risk would be elderly patients for whom a slight increase in blood pressure could have major negative repercussions.
A bigger question is whether Americans have become too comfortable with popping a pill for pain or other discomfort.
Heavy use of nonprescription painkillers like Tylenol, aspirin and ibuprofen have been associated with chronic kidney disease. Tylenol at high doses can be toxic to the liver. In 2000, the Food and Drug Administration pulled over-the-counter nasal decongestants that contained phenylpropanolamine because it was associate with strokes.
"We should avoid the belief that all OTC medications are safe, when, in fact, they are not," says Forman. "By pointing out potential risks associated with these drugs, more informed choices can be made by women and their clinicians."
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