by Ronald L. Hoffman, M.D., CNS
Q. What kinds of undiagnosed illnesses can be present with a primary symptom of fatigue? Would other symptoms likely be present, too? How can the fatigue be alleviated with proper treatment of the illness?
A. There are innumerable serious and minor illnesses that are present in this fashion. Most infectious diseases are associated with production of cytokines, substances that prime the immune response but which make you feel flu-like. In fact treatments for cancer, hepatitis, and multiple sclerosis which use interferon, an immune booster, often have the side effect of making you tired. The evolutionary reason for cytokine-mediated fatigue is that it makes you slow down and rest, conserving the body's resources for fighting infection.
Overwhelming fatigue is an ominous warning sign of an impending heart attack according to recent research. It can also be a sign of an undiagnosed cancer, particularly one that causes anemia through hidden bleeding as in colon cancer, or by affecting the bone marrow or blood as in leukemia or multiple myeloma.
Multiple sclerosis sometimes presents with fatigue, although it is usually accompanied by specific nerve problems.
The key glandular problems associated with fatigue are hypothyroidism and more rarely, adrenal insufficiency. These can be alleviated with medication that mimics the actions of the hormones we normally produce.
In women, the most common condition that causes fatigue is iron-deficiency anemia caused by excessive menstrual bleeding, sometimes coupled with inadequate diet. (But the most common non-disease cause of fatigue in women overall is sleep-deprivation caused by competing demands of family, job etc.)
Sleep disorders, of course, cause fatigue, and while this is usually obvious, in sleep apnea, frequent awakenings can leave the sufferer drowsy even if he/she remains unaware.
Finally, depression is a major hidden cause of fatigue. Anti-depressants can sometimes alleviate.
Q. What types of medications (both prescription and over-the-counter) can cause fatigue or drowsiness? What's the mechanism? What should people do if they suspect this is happening to them?
A. Virtually any medication can cause fatigue in a minority of users. These reactions are called "idiosyncratic" because they are quirky and particular to an individual's unique makeup. But other medications typically cause fatigue as a consequence of their intended mode of action. Typically, these are drugs that alleviate conditions by slowing down the nervous system.
Many heart and high blood pressure medications can cause fatigue. They may slow down the pumping action of the heart, tone down the nervous system, or as with diuretics, deplete the body of minerals.
OTC allergy medications and cold formulas that contain antihistamines can cause drowsiness and even impair driving skills. Anti-anxiety medications usually cause sleepiness and fatigue. A "PM" designation on a product usually suggests that it will cause drowsiness.
Cancer chemotherapy drugs almost always cause fatigue. A new drug called Pro-crit is being marketed to reverse this fatigue, because it restores red blood cell counts depleted by chemo.
Paradoxically, stimulant drugs and even excess caffeine can worsen the fatigue they're intended to alleviate. This is because they deplete energy reserves: after an initial high, the user crashes.
If you suspect a medication is causing fatigue, check with your doctor. The sudden cessation of certain medications can have dangerous effects. Usually, an alternative medication can be safely substituted. Or else, diet and lifestyle changes can alleviate the condition that necessitated the medication.
Q. Can gaining a slight amount of weight (say, five to ten pounds) compromise a person's energy level? If so, how? What should she do about it?
A .The answer is yes. If you have any doubt of this, carry an 8 lb lap-top to the top floor of a 5 floor walkup apartment and see if you don't feel more winded. SLOW weight loss through a non-starvation diet is the answer, because rapid precipitous weight loss causes loss of muscle and leaves you nutritionally depleted.
Q. Are there any other health-related habits (aside from nutritional issues) that can drain a person's energy?
A. Inactivity is paradoxically a big contributor to fatigue. A regular exercise program, if not taken to extremes, is a major bulwark against fatigue.
Q. I've heard that diseases such as Lyme disease, diabetes, and allergies can also cause noticeable fatigue--is this true?
A. Absolutely! However fatigue is seldom the isolated manifestation of these conditions. In Lyme, we often see joint pain, stiff neck, or Bell's Palsy. Depending on the type of diabetes you see weight gain or loss, carbohydrate cravings, or thirst and urination. A prelude to diabetes called Syndrome X is often accompanied by fatigue. A common feature of diabetes is the inability to convert dietary calories into energy output, resulting in a buildup of blood sugar, and power failure in the muscles and brain.
Allergies, too, can cause chronic fatigue. For instance, individuals with chronic sinusitis, which is often prompted by allergies to environmental inhalants and worsened by reliance on mucus-forming foods, feel constantly tired and report "brain fog" symptoms.
Q. Can hepatitis itself also make you tired?
A. Absolutely. A concern is that a lot of Americans are walking around with undiagnosed chronic hepatitis--especially hepatitis C. A blood test can yield a diagnosis, and new therapies are available to prevent liver damage which can sometimes necessitate a liver transplant.
Q. Finally, what should a person do if he or she has unexplained fatigue that is suspected to be due to an underlying medical condition (or depression)?
A. A doctor visit is in order if a person suspects a medical or psychological condition is prompting fatigue. Obvious causes are likely to be discovered, but subtle causes like food allergies or Syndrome X or "couch potato syndrome" won't be. Consultation with a nutritionally-oriented practitioner or an alternative physician may yield a solution.
Q. How long should a person wait to seek medical attention (assuming he or she tries to improve lifestyle first)?
A. I generally suggest a 6 to 8 week trial of lifestyle change for mild fatigue symptoms. If there's no sign of improvement with proper rest, exercise, elimination of stimulants, cessation of alcohol and other recreational drugs, diet modification and the use of basic balanced nutritional supplements, fatigue may be a warning sign of a more serious underlying medical or psychological condition.
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