162 Synthroid to NP thyroid equivalance

[AJWS6]

Hi, was wondering if anyone knew the equivalance of 162 Synthoid to NP thyroid ?  Synthroid or elevated T3 is causing my nervous condition.  Past few day's, upon waking I'm fine, I take synthroid approx 2 hours later, the nervous condition kicks in.  I've taken Synthroid for past 9 months, no problems till approx 3 weeks ago.  Trying to figure out what's causing jittery conditon.  My whole body constantly shaking, after a few hours calms down, I get headache, then exhausted.  I have labs Aug 19th.  Depending upon labs, was thinking of trying natural hormone.  My body does not do well on synthetic meds, including diabetic meds, works fine on natural insulin.  

Synthetic meds alway's work at first, but then stops working after a few months.    

My body likes low T3, between 2.5 - 2.7 range (2.5 - 3.9), NP thyroid has T3.  If anyone can assist with calculation, truly appreciated.      

[gimel]

Even though most of the conversion charts show 100 mcg of T4 as being equivalent to one grain of desiccated, when you look further it gets confusing.  Those charts also show that 25 mcg of T3 is supposedly equal to 100 mcg of T4.  If that is true then one grain of desiccated would be only equivalent to 75 mcg of T4.  The math is this:  one grain = 39 mcg of T4 plus 9 mcg of T3.  So if you multiple the 9 mcg of T3 by 4 and add the 39 mcg of T4 that would only add to 75 mcg of T4, not 100 mcg.  In addition, there is a scientific study that attempted to determine the T4 equivalent of T3.  They came to the conclusion that one mcg of T3 was approx. equal to 3.3 mcg of T4.  In that case one grain of desiccated would be approximately the equivalent of 69 mcg of T4 (39 mcg of T4 plus 3.3 times 9 mcg of T3 = 68.7 mcg of T4).  So from that data, 162 mcg of T4 would be equivalent to about 2.3 grains of desiccated.  

So equivalency is just an estimate of where to start with the change.  This doesn't change the validity of goolarra's suggestion to start on the low side and increase slowly.  It just indicates that the equivalent dose of desiccated is higher than the conversion charts indicate.  But that really doesn't make much difference if the patient is treated clinically, as necessary to relieve symptoms, rather than by lab results.  

[goolarra]

100 mcg is roughly equivalent to 1 grain of desiccated.  So, 162 mcg converts to about 1.62 grains.  However, keep in mind that these are not really equivalents...they are very different meds.  So, the equivalency is more of a place to start when switching.  You probably want to start out on the low side if you're not used to taking T3, especially if your FT3 is "elevated", which I assume means higher than you normally like it???