Medical Edge Newspaper Column

Even Those In Peak Health Can Succumb To Fatigue

Feb. 5, 2006
DEAR MAYO CLINIC:
I'm an active 53-year-old woman. I eat well and run about 40 miles a week. Recently, I began feeling overwhelmingly fatigued and was diagnosed with mononucleosis -- for the third time. Why do I keep getting it? Is there anything I can do to speed my recovery and prevent future bouts?

ANSWER:
It's great that you are doing so much to stay healthy -- especially running 40 miles a week!

Fatigue can occur even when you are making many healthy choices. In fact, acute fatigue is one of the most common reasons patients come to see primary care providers. Because there are so many possible causes, it can be difficult to pinpoint the reason.

The search should begin with a comprehensive history and exam that covers:

• Other symptoms: Cold dry skin could point to a thyroid disorder, a common cause of fatigue. Night sweats and lymph node swelling along with fatigue can be symptoms of an underlying malignancy such as lymphoma or a systemic infection. Seasonal allergies can also make you feel very tired.

• Other illnesses: Extreme fatigue can be a warning sign of diabetes. It's associated with many other illnesses, too, such as fibromyalgia, heart disease, lung disease, muscle disease and several others. Sleep apnea is a common cause of fatigue because it interferes with sound sleep.

• Medications: Some cause sleepiness, while others, including stimulants, can interfere with quality sleep.

• Mental health issues: Depression can zap your energy.

• Lifestyle choices: It's basic, but are you getting enough sleep? Managing stress? Really eating well? If you're a vegetarian, it's easy to be low on iron in your diet -- another possible cause of fatigue. Too much caffeine or alcohol can leave you feeling tired.

I suggest you work closely with a physician to pinpoint the cause of your fatigue and develop a treatment plan. From what you've shared, mononucleosis is probably not the cause.

Once you've had the "mono virus," also called the Epstein-Barr virus, you usually have antibodies to it in your blood for the rest of your life. While recovery from mono can take weeks, you are unlikely to contract it again because your body has created these antibodies. It is probable that only one of your three episodes was due to true Epstein-Barr virus.

-- Margaret Houston, M.D., Family Medicine, Mayo Clinic, Rochester, Minn.