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Unexplained Weight Loss

What is unexplained weight loss?

Your weight sometimes changes, depending on how much you eat and exercise. However, drastic weight loss, losing more than 10 pounds when you're not trying to, requires medical attention because it may be a sign of illness.

How does it occur?

If you are not trying to lose weight, the loss may be a symptom, alone or with other symptoms, of disease.

Unexplained weight loss can be caused by:

  • decreased appetite
  • decreased absorption, which means that food can't be digested properly
  • excess demand by the body for energy (calories).

Decreased appetite can be caused by the following:

  • poorly fitting dentures or pain in the teeth or mouth
  • psychological disorders that upset eating habits (anorexia nervosa and bulimia)
  • depression or anxiety
  • drugs such as digitalis, amphetamines, and antitumor medicines
  • a high level of calcium in the blood (hypercalcemia)
  • a low level of potassium in the blood (hypokalemia)
  • alcohol abuse
  • viral hepatitis, an infection of the liver
  • congestive heart failure
  • cancer.

Decreased absorption can be caused by:

  • gallbladder problems
  • not enough digestion enzymes
  • stomach surgery (gastrectomy)
  • problems with the small intestine
  • parasitic infection, such as trichinosis, which is caused by uncooked pork
  • drugs such as cholestyramine and cathartics, which may Cause the bowel to empty too fast.

Loss of nutrients can be caused by:

  • diabetes, when the blood sugar is too high
  • long-lasting diarrhea
  • frequent or long-lasting vomiting
  • kidney disease.

Excess demand for energy can be caused by:

  • overactive thyroid glands and too much thyroid hormone, which speeds up the body's metabolism (hyperthyroidism)
  • fever
  • emotional states, such as manic disease, that cause increased physical activity
  • hyperactivity
  • amphetamine or other drug abuse
  • cancer.

How is it diagnosed?

To look for the underlying cause of weight loss, your health care provider will ask about your medical history and examine you. In addition, your provider may order various lab tests such as blood tests, for example, for hyperthyroidism.

How is it treated?

First your health care provider will work to identify and correct the underlying problem. Then your provider will also help you with your symptoms. Here are some examples of treatment:

  • For severe anorexia, your health care provider may prescribe counseling and medicine.
  • For decreased appetite, your provider may suggest eating small, frequent meals. Eating more of your favorite foods may help. Eating more protein may also be important.
  • For decreased appetite due to nausea, your provider may suggest eating small, frequent meals, especially at the times when nausea is milder. You may need anti-nausea medicine.
  • For decreased appetite associated with depression, your provider may suggest counseling and antidepressant medicine.
  • For decreased absorption caused by problems with your pancreas, your provider may prescribe pancreatic enzyme preparations.
  • For infections, your provider may prescribe medicine, such as antibiotics.
  • For loss of nutrients, your provider may prescribe fat-soluble vitamins A, D, and K. Your provider may give you medicine to help severe diarrhea and vomiting.

How can I take care of myself?

To help take care of yourself, follow your health care provider's instructions. If you suspect you are losing weight, weigh yourself every week. If you have lost more than 5 to 10 pounds in a month without trying, you should consult your health care provider.

Developed by McKesson Health Solutions LLC.
This content is reviewed periodically and is subject to change as new health information becomes available. The information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional.
Copyright © 2003 McKesson Health Solutions LLC. All rights reserved.
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