It's natural for men to notice a gradual decrease in sex drive (libido) as they age. The degree of this decline varies, but most men maintain at least some amount of sexual interest well into their 60s and 70s.

Sometimes, however, loss of sex drive is related to an underlying condition. Depression and stress often contribute to loss of sex drive in men.

Sometimes the culprit is a decrease in male sex hormones due to an endocrine disorder. In other cases, loss of sex drive may be a medication side effect.

If you're concerned about loss of sex drive — especially if the loss happened abruptly — consult your doctor. He or she will likely take a detailed history, do a physical exam and request lab tests to help determine what's causing the loss of sex drive.

Once any underlying factors are identified, your doctor can suggest appropriate treatment options. For example:

• If loss of sex drive is related to stress or depression, psychotherapy alone or in combination with antidepressant medication may help.
• Some medical conditions, such as obstructive sleep apnea, can cause an unusually low testosterone level, and treatment can return your testosterone level and sex drive to normal. If no medical cause is found, treatment options may include testosterone replacement therapy.
• If a certain medication is contributing to loss of sex drive, your doctor may suggest an alternate drug.

Some people have a hard time discussing sex with their doctors. But treatments are often available for a loss of sex drive, so it's worth it to have an open and honest talk with your doctor.