DEAR DOCTOR K: For the past few months I just haven't had my usual energy. Should I see a doctor?
DEAR READER: We all have times when we lack energy; it's a universal human experience. We can often pinpoint the cause: hard physical or mental work, an ongoing stressful situation, lack of enough good-quality sleep.
Most people probably also experience times when they lack energy or feel unusually tired but cannot pinpoint the cause. Sometimes it's a brief infectious illness that hasn't produced the usual symptoms, such as sneezing, body aches or fever. Sometimes, it's just a mystery.
According to surveys, about 20% of people will say "yes" if you stop them in the street and ask if they are feeling unusually tired for no good reason. Most of them will never contact their doctor about it, figuring it will pass.
Still, fatigue is one of the most common reasons that people do seek medical care. My general advice is to contact your doctor if you're so tired you can't get out of bed, or if you experience fatigue or lack of energy that is very unusual for you — more intense or more long-lasting.
Two of the most common causes of fatigue are depression and just plain overwork. Fatigue may be a side effect of medication or the result of poor sleep habits. Or it may be caused by one of many illnesses, from chronic fatigue syndrome and fibromyalgia, to anaemia, heart failure or multiple sclerosis.
Start by talking to your primary care physician. He or she will ask questions and perform a physical examination designed to root out any underlying medical or psychological illness. Many illnesses can cause fatigue. Describe your symptoms in detail to help your doctor narrow down the possible causes. For example:
- Do you have trouble concentrating?
- Do you tire more quickly than usual?
- Do certain activities take more effort than they used to?
As another example, think about which activities you've had to limit. For example:
- You can no longer stay awake for dinner and a movie.
- You no longer wake up feeling refreshed, even after you've slept all night.
- When you exercise, your muscles feel achy and weak in less time than they once did.
Timing is also important. Tell the doctor when you started noticing a decrease in your physical or mental energy level. Was the change gradual or sudden? Did the onset of fatigue coincide with any other significant change in your life: Had you been ill? Was there a death in the family?
Also, make sure to tell your doctor about any other symptoms you might be experiencing along with the lack of energy. Do you get out of breath easily? Do your muscles or joints ache? Do you have trouble sleeping? Are you feeling unusually sad or anxious? Different symptoms accompanying fatigue suggest different causes.
No matter the root of your problem, there are treatments and practical strategies that can help restore your energy. The first step is to talk to your doctor.
Dr Anthony L. Komaroff is a physician and professor at Harvard Medical School.
