13 year old, Fatigue, Faints, tachycardia, nausea

I am thirteen, and for the past 2 months I have been really pale, tired and weak. 2 days ago I threw up 5 times and in the morning I woke up and was sitting on a chair and fainted, all color was drawn out of my face and my lips were blue. I was rushed to the hospital and they took ex-rays of my head and heart size everything was fine. My heart beat was 178 when I stood up and around 105 when laying down. They gave me fluids and said I was fine and sent me home. I still feel tachycardic and I am showing fatigue. The heart beat is not normal for me I am a long distance runner, my normal heart rate is 55-60 and I ride horses. I weigh 87 pounds, and I am 5' 4". I do not know what is wrong, do you?

[Dr. Kokil Mathur]

Hi!
The simplest reason for extreme tiredness fatigue, fainting, nausea etc can be anemia. So get your iron and hemoglobin levels checked. Another possibility is sleep disturbances (like sleep apnea, imbalance of rapid eye and non rapid eye movement sleep etc.). You may sleep your customary 7-8 hours and yet feel fatigued. You need sleep studies to rule this out. Other possibilities are chronic fatigue syndrome, depression, low Vit B12, low iron, low calcium, sodium and potassium. Hyperthyroidism too causes increased sweating and tiredness.   Postviral fatigue syndrome is another possibility. Persisting EBV infection or mono can also be the cause. A comprehensive investigation is required keeping all the points in mind. Do discuss this with your doctor and get yourself examined.
Take care!

[sarah0683]

Youshouldhaveatilttabletestdone.Andalsoautonomictesting.TrygooglingPposturalOrthostaticTachycardiaSyndrome.Itsverycommoninteenagersandluckilythesymptomsseemtodisappearlateroninyourlateteens.Ifthishaspersistediwouldstronglyreccommendspeakingwithyourdoctorregardinghavingsomeautonomicfunctiontests.

[sarah0683]

My apologies, I clearly cannot post from my blackberry!  
What I was trying to say is you should have a tilt table test done to test for autonomic dysfunction. Try googling Postural Orthostatis Tachycardia Syndrome and see if you can relate to some of these symptoms. It seems to be common in teenagers. It can disappear in your late teens to early 20's.

Some doctors have never even heard of POTS. I have had POTS now for 3 years and my symptoms started alot like yours.

It may not be what is wrong with you but its a suggestion and like I said before sounds very much like how I felt when my POTS was diagnosed.

Did they do an ekg at the hospital when your heart rate was at 178? Does your heart rate increase every time you stand up? There is also a forum on here that is called "Dysautonomia" there is lots of good information.

I hope you are feeling better and are no longer having these issues!!