The United States Food and Drug Administration told manufacturers of testosterone products to put a warning label about the general risk of blood clots.

At present, the testosterone products available in the market inform customers about the risk of blood clots related to a condition known as polycythemia, a rare condition that happens when the red blood cell level increases abnormally because of the testosterone treatment. But, FDA stated that blood clot risk in the vein that includes deep vein thrombosis (DVT) and pulmonary embolism was aggravated in people without the condition.

According to FDA, people undergoing testosterone treatments might have increased risk of blood clots, even though they do not have polycythemia. Testosterone treatments are prescribed to men who lack or have extremely low levels of the hormone usually due to medical conditions. Men with testosterone problems mostly suffer from symptoms such as loss of libido, depression, fatigue and reduced muscle mass.

Health officials are investigating the possible side effects of taking testosterone treatments.

"FDA is investigating the risk of stroke, heart attack and death in men taking FDA-approved testosterone products," FDA stated. "We have been monitoring this risk and decided to reassess this safety issue based on the recent publication of two separate studies that each suggested an increased risk of cardiovascular events among groups of men prescribed testosterone therapy."

Recent studies showed that they were not related to this ongoing investigation. The agency added that patients should consult with their doctors about the treatment plans and address the potential risks involved.