When to see a doctor about changes in appetite

When your body speaks, you should listen — but most people aren't very good at it, and it's tempting to ignore potential problems. Use the information here to help decide how urgently you need to see your doctor.

• Decreased appetite accompanied by fatigue, hair loss or decreased cold tolerance: Hypothyroidism (underactive thyroid). See your doctor, who will order a diagnostic blood test. If your thyroid is underactive, treatment is thyroid hormone replacement pills
• Decreased appetite accompanied by other symptoms, including changes in bowel habits; fatigue; nausea; or bloody stools, urine or vomit: Cancer. See your doctor, who may order diagnostic tests
• Decreased appetite after starting a new medication: A side effect of medications such as cancer drugs, some antibiotics, narcotic pain relievers and some cough and cold preparations. Talk with your doctor about whether a different drug should be substituted. Side effects sometimes disappear after a few days or weeks of taking a medication
• Increased appetite accompanied by insomnia, excessive thirst, increased sweating, more frequent bowel movements or hair loss: Hyperthyroidism (Graves' disease) or other hormone imbalance. See your doctor, who will order diagnostic blood tests. If your thyroid is overactive, prescription medication can slow it down
• Increased appetite accompanied by excessive thirst, fatigue, increased urination or poor wound healing: Diabetes. See your doctor, who will order a test to measure your blood sugar
• Increased appetite after starting a new medication: A side effect of medications such as corticosteroids, some antidepressants and some allergy medications. Talk with your doctor about whether a different drug should be substituted. Side effects sometimes disappear after a few days or weeks of taking a medication

Even if you do pay attention to your symptoms, it's not easy to know what they mean. That's why diagnosis is a job for a doctor when you are experiencing changes in appetite.