What tests are available to check for low testosterone levels?

The most common test for checking testosterone levels as of 2015 is a blood test, according to WebMD. Total testosterone levels for men should fall between 270 and 1,070 nanograms per deciliter, while free testosterone levels should be from 50 to 210 picograms per milliliter.

Low testosterone values in men may indicate a problem with the testicles or pituitary gland, notes WebMD. Certain genetic diseases can also cause low testosterone, including Down syndrome and Klinefelter syndrome. Likewise, cirrhosis of the liver can cause a decrease in testosterone, as can treatments for prostate cancer. Chronic long-term abuse of alcohol can be the cause of low levels of testosterone.