Drug companies market testosterone pills and creams to ease symptoms such as low libido, a decrease in life satisfaction, or “a recent deterioration in your ability to play sports.” But emerging research is showing that testosterone treatments may create problems of their own, including an increased risk of heart attacks. 

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FDA Is Reviewing Testosterone Therapies

The U.S. Food and Drug Administration (FDA) has approved testosterone therapies, but it recently announced that it is reassessing the safety of those treatments after two studies linked them with an increase in heart problems.

“At this time, FDA has not concluded that FDA-approved testosterone treatment increases the risk of stroke, heart attack, or death,” the FDA said in a press release. "Patients should not stop taking prescribed testosterone products without first discussing any questions or concerns with their health care professionals.”

The FDA does, however, urge doctors to weigh the benefits of testosterone therapy against potential heart risks.

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Studies Link Extra Testosterone to Heart Problems

One recent study, published in the journal PLOS ONE, found a two-fold increase in the risk of heart attack in men 65 or older within 90 days of beginning testosterone therapy. Those under the age of 65 with a history of heart disease had a two- to three-fold increased risk of having a heart attack in the same time period. Younger men without a history of heart problems had no increased risk, the study showed.

The initial study that piqued the FDA’s interest appeared in the Journal of the American Medical Association in November. That study examined the records of 8,709 U.S. veterans who had low levels of testosterone and underwent blood vessel imaging to gauge their risk of coronary artery disease.

Researchers discovered that the 1,223 men who had undergone testosterone therapy, who were about 60 years old on average, had a 30 percent greater risk of stroke, heart attack, and death compared to men who hadn't receive extra testosterone.

A smaller study published in the New England Journal of Medicine in 2010, examining the effect of testosterone gel on muscle function in men 65 or older, was discontinued due to cardiac, respiratory, and skin problems in the men being treated. Many did, however, experience an increase in muscle strength before therapy was ended.

But there is little evidence that testosterone therapy has any positive effect on heart health. A study in the Journal of Clinical Endocrinology & Metabolism examined the connection between testosterone and cardiovascular events in studies from 1970 and 2013. Researchers found that men with low testosterone levels may have a slightly elevated risk of developing or dying from heart disease. The study's senior author Dr. Johannes Ruige of Ghent University Hospital in Belgium, said testosterone replacement therapy did not have any beneficial effect on heart health.

“Although the number of older and middle-aged men who are being prescribed testosterone replacement therapy is rising rapidly, there is debate about whether the practice is too widespread,” he said in a statement. “In its testosterone therapy clinical practice guidelines, the Endocrine Society recommends treating only men who have unequivocally low testosterone levels and consistent symptoms.”

Approved Uses for Testosterone Therapy Are Limited

The FDA has approved various forms of testosterone therapy for men who have low levels of testosterone caused by medical conditions where the testicles fail to produce the hormone, including genetic problems and the side effects of chemotherapy.

Other medical conditions include problems with the hypothalamus and pituitary gland, two brain structures that control testosterone production.

“None of the FDA-approved testosterone products are approved for use in men with low testosterone levels who lack an associated medical condition,” the FDA stated.