3 year old jerking

My son will be 3 years old on May 7.  In February my wife noticed that his arms would sometimes jerk when he was in a relaxed state.  I didn't notice the jerking and discounted it.  However, now I have noticed the jerking in his arms, sometimes with a corresponding movement of his head.  Yesterday, he had several episodes of the jerking when he was awake.  I have also noticed that sometimes when he is in the first stages of sleep he will experience the jerking motion for up to 10 minutes.  This doesn't happen on a daily basis, and always seems to happen when he is tired.

Last summer, we found out that he has severe allergies to grasses, trees, dust, tobacco, and some foods.  In October, he started taking shots and Zrytec on a regular basis.  And, over the course of the winter, we have given him other antihistamines, decongestants, and pain relievers for common colds symptoms.  Could any of these medications be causing these jerks?

We have also noticed that he snores and is a restless sleeper.  He sleeps in very bizarre positions.  We are wondering if sleep apnea could also be another factor causing this problem.  

He has had an EEG that showed myoclonic jerks in the first stages of his sleep, but it did not show any seizure activity.  During the testing, the technician was concerned about his oxygen saturation.  So, she placed a monitor on him and said that his oxygen saturation was at times in the low 80's.  The doctor discounted this information for whatever reason, but we are still concerned.  Should we be concerned?

Thank you in advance for your help.

Howard

[CCF-Neuro-M.D.-JT]

Hard to say what your son is doing without actually seeing it for myself, but it sounds like the jerks may be myoclonic jerks, which can certainly be caused by some drugs.  Pseudoephedrine which is a component of many decongestants can cause hyperexcitability and nervousness, which may be exacerbating or even causing the jerks.  Didn't find any reports on zyrtec and nothing on antihistamines doing the same thing. Sleep start or hypnic jerks are also a possiblity in which this is a normal response to falling asleep, but can be exaggerated in some people. Seizures are also another possiblity.  If he is developmentally normal and the EEG was normal, then that is reasurring.  But at any rate, a pediatric neurologist should get a look at him to make sure everything is ok.

Finally, there are strict criteria for diagnosing apnea in sleep.  So just because the oxygen level drops (even to 80s) it does not necessarily mean that a patient has sleep apnea.  Standard definition includes a time minimum of 10 seconds for each episode as well as other criteria. As I did not perform the study or review the results, it's difficult for me to give an accurate opinion. But if you are still concerned (which is certainly justified given that it's your child), then talk to the doctor and pin him/her down on exactly why she/he's not calling it apnea. Best of luck to your son and family.

[katiejmarr]

A related discussion, 5 year old jerking was started.