Asthma - Eosinophil

I had some labwork done recently, and my Eosinophil level was a little elevated at 5%.  I have a history with Asthma, but am not currently on any medication.  At one time I was prescribed Advair and Albuterol.  I have recently switched doctors, and wondering if I should bring up the Asthma, since it had been acting up lately.  Also, I should mention that I have a thyroid disorder that has been acting up as well and my medication (levothyroxin (levothyroxine)) has been upped just a week ago.   I am unaware of any complications with meds for asthma and thyroid.  My question basically is, could my eosinophil be higher because of my untreated asthma? and Is asthma something that should always be treated?
I have had tendancy to only do something about it when it gets really bad, thinking that otherwise it is fine.

[National Jewish Health]

A 5% eosinophil level is probably within or near normal limits.  However, if your level is usually 0 to 1%, then 5% could be a sign of allergic activity and, if so, point to a cause of your recent asthma worsening.  Yes, you should “bring-up” asthma with your new doctor, so that he/she can get an estimate of your asthma severity and asthma control.  The guidelines for daily drug therapy are based on a combination of severity and control and your doctor would be familiar with these National Heart, Lung, and Blood Institute (NHLBI) guidelines.

Whether daily therapy is recommended or not depends, in large measure, on whether your asthma is intermittent or persistent based upon the guideline definition.  But if intermittent, the decision on continuous therapy is dependant upon the frequency and severity of exacerbations.

At this point, you should probably be on daily therapy for a while; at least until your asthma is optimally controlled and remains controlled for 2 to 3 months.

There are no significant interactions between asthma medicines and thyroid medicines, or between the 2 diseases.

Good luck.