Chronic Fatigue Syndrome/I'm constantly fatigued


QUESTION: A few years ago i caught mononucleosis and the fatigue hasn't gone away. I feel like it has gotten worse and the fatigue is much more mental than it is physical. I can lift and exercise but i find it exhausting to think and socialize with people. I've seen some doctors and they ran blood tests but couldnt find anything wrong. Now, they put me on antidepressants which isn't helping me very much. Is it likely that i have chronic fatigue syndrome?

ANSWER: Dear Phillip -

First, I apologize for the delay in responding to you. My own health was poor this week, so I got behind on e-mails, etc.

What you're describing DOES sound like CFS, also known as ME, myalgic encephalomyelitis. It very often begins with some sort of infection that triggers immune system changes, and mono is a known trigger for CFS.

The one thing you say that doesn't fit with a CFS diagnosis is that you say you can exercise. One of the defining characteristics of CFS is that it causes an exercise intolerance, also known as post-exertional malaise (PEM). However, before you understand how it works, it is a pattern that you might not recognize. PEM doesn't mean you CAN'T exercise, but it causes a reaction afterward that is sometimes delayed by a day or even 2. What happens is that when you do exercise or over-exert (especially aerobic exercise), anywhere from a few hours to a few days later, you suddenly feel as if you've got the flu - severe and sudden exhaustion, often sore throat, flu-like aches, etc. In fact, it can feel like you've got mono again! So, think back to the times when you've exercised or maybe even begin keeping track of your symptoms and how you feel and exertion level on a calendar to see if that pattern emerges.

Here's some more information about ME/CFS:

At the bottom of that page is a button for a self-quiz to help figure out if you have it or not.

If you think you might have ME/CFS, here are some databases for finding a doctor in your area who understands and treats CFS:

There are about a dozen or so top CFS experts in the US. If you do think you have CFS and want to see one of the top docs, let me know what state or region you live in, and I can tell you who you're closest to.

Good luck finding answers - I understand how difficult and frustrating it can be to be sick and not know why!

Sue Jackson

---------- FOLLOW-UP ----------

QUESTION: Thank you for your reply. When I first caught mono I didn't have any flu like symptoms. Simply one day I began feeling lacking in energy and after I got the blood test, i was told that I have mono. Right now, I've currently seen many doctors and all of them have been adamant that I have depression. The problem with that is I am not sad or easily agitated. I've been on antidepressants for a month now and it hasn't been very fruitful. I've mentioned CFS to my doctors and they've all said that it is probable but have never been serious with the idea. I also have some minor symptoms accompanying my fatigue that weren't there when I had mono, such as tinnitus. There are no flu like symptoms after I excercise. Also, a year ago I began feeling symptoms that matched hypothyroidism and a doctor said that I had borderline hypothyroidism from my blood test. The symptoms are all gone now on their own. So, I would like to make sure that it is unlikely that I have Chronic fatigue syndrome. Do you think it is likely CFS? Could my symptoms match anything else?

Well, the exercise intolerance is considered to be the central characteristic of CFS, so if you don't have that, then CFS is less likely...but the illness starting with mono DOES sound like CFS.

Ignore the doctors that keep telling you you are just depressed - you know your own body and know when something is wrong and/or has changed.

Consider finding a doctor from those lists I sent you who understands CFS to be evaluated - they will not only know CFS but will be open-minded and diligent about helping you find what's wrong even if it is not CFS.

Good luck!


Chronic Fatigue Syndrome

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Suzan Jackson


I have had CFS since March 2002. My 14-year old son and 10-year old son also has CFS. I have a scientific background (chemical engineering) and have read and researched extensively to try to help myself and my sons to improve our symptoms, with some success. I`ve also conferred with some of the top CFS doctors in the U.S. I have a lot of hard-won experience working with school systems to get appropriate support for my sons. This is a very debilitating and isolating illness, and I would be glad to help anyone else who is struggling with CFS themselves or with a family member. You can read about our experiences in learning to live with CFS at my blog:


Have had CFS/CFIDS since 2002.
Two young sons have CFS/CFIDS.

CFIDS Association of America
Various listserves that provide up-to-date information on CFS research.


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