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Testosterone Therapy & Blood Clots, Strokes

Low T Therapy Side Effects Emergency SignMedically boosting testosterone levels in men with deficiencies can be dangerous to one’s health—or, so a growing body of literature seems to suggest.  Recent studies have established a link between Low T therapies such as the popular drug AndroGel (among many other supplements for declining male virility) and increased risks of blood clots and strokes.

This link between testosterone therapy and blood clots and strokes warrants caution both for men currently on Low T therapies and for those considering the prospect; it is also the fodder for a number of product liability claims alleging Low T therapies caused life-threatening complications and sudden death.

Low T therapies and blood clots

Blood clotting is often a healthy bodily reflex to bleeding from a traumatic injury.  However, in patients taking Low T therapies, the side effect of blood clotting is more likely to occur on its own, in the absence of a traumatic injury.

When this happens, the results can be serious.  A number of things can happen:

  • Deep-vein thrombosis (DVT) is what takes place when blood congeals in massive amounts in a major vein and/or artery, often in the legs, cutting off blood flow. DVT is very dangerous and can be fatal: if it travels into the bloodstream, for example, it can cut off blood flowing to the lungs via a “pulmonary embolism.”  Pulmonary embolisms kill more people in the U.S. each year than breast, prostate, colon and skin cancer combined.  A DVT can also travel to the brain and cause a massive stroke.
  • Polycythemia, a blood-related disorder, can also result when an increase in testosterone in turn spikes the production of hemoglobin, hematocrit and/or red blood cells, with the consequence that blood thickens and blood pressure increases.  (Any time blood circulation slows, the risks of clotting go up.)
  • Blood vessels can constrict with an increase in the lipid thromboxane (another Low T therapy side effect).  This problem, coupled with a more aggressive production of red blood cells, thanks again to increased testosterone levels, can quickly become a blood clot waiting to happen.

Studies, FDA reinforce Low T therapy link to blood clots

Recent studies have drawn compelling links between testosterone boosting therapies and prospects of blood clotting.  For example, a study published in the August 2013 issue of Clinical and Applied Thrombosis/Hemostasis found blood clots can set in as quickly as within one month of undergoing Low T therapy.

The author of that study, Dr. Charles Glueck of the Jewish Hospital Cholesterol and Metabolism Center, told the Cincinnati Business Courier that a notable number of men hospitalized for life-threatening blood clots developed these conditions within three months of starting testosterone therapy.

The U.S. Food and Drug Administration (FDA) has also issued a warning alerting potential recipients about risks of adverse testosterone side effects.

Testosterone and stroke risks

Like blood clots, strokes tend to become a more present danger for men taking testosterone therapies, too.  Strokes, which according to the American Stroke Association are the fourth leading cause of death in this country, occur whenever a blockage of blood flow to the brain occurs.

In many cases, a blood clot can lead to a stroke.  The brain depends on receiving key nutrients sent to it by the arteries.  When one or more of these arteries is blocked, this critical blood supply can no longer reach the brain, (in what is called an “ischemic stroke”).  Symptoms of an ischemic stroke vary based on the area of the brain affected, but can include permanently impaired vision, speech, memory and movement.  Some 85 percent of strokes are ischemic, which fall into one of two categories, thrombotic (caused by a clot in an artery to the brain) or embolic (caused by a clot in the heart).

There is also such a thing as a “transient ischemic attack” (TIA), which is a milder, more short-lived “mini” stroke of sorts, usually exhibiting temporary symptoms.

Another kind of stroke associated with Low T therapies is known as a hemorrhagic rupture, which occurs when a blood vessel in the brain leaks or bursts.

In all of these cases, whenever a stroke is suspected, immediate emergency treatment should be sought.

At the start of this year, the FDA embarked on an official review of suspected links between Low T therapies and heart attack risks.  The FDA’s review comes on the heels of two seminal studies published in reputable publications.  The first, in the Journal of the American Medical Associations, concluded that at least in older men, risks of stroke, heart attack and death rise by 30 percent with Low T supplements.  The second study, published in PLOS One, similarly reported a significant leap in risks of heart attack for both younger and older men taking Low T therapies.

Allegations leveled in Low T lawsuits

In the meantime, testosterone therapy lawsuits have been emerging across the country aimed at the various makers of drugs like Androgel, Testim and others.  Plaintiffs are claiming the supplements were the cause of their pain and suffering in the form of serious side effects ranging from mini strokes and blood clots to heart attacks.

  1. Harvard Health Publications, “FDA warns about blood clot risk with testosterone products,”
  2. Mayo Clinic, “Strokes,”