The Armour contains BOTH T4 hormone as well as T3 hormone.
Armour and any natural dessicated thyroid medicine have both components. And they are made from pig thyroids. It just so happens pig thyroid has about 4 times as much T3 in it than a human. So what this means is that with Armour you get a LOT more T3 than what your body's own thyroid produces.
This is not necessarily bad as many people need more T3. And ultimately you body uses the Free isolated T3 hormone molecule. The T4 molecule has to go through the step of being converted into T3. The T3 in the medication however is available to you body almost immediately.
More technically, it takes up to 6 WEEKS for the level of T4 in your blood to stabilize from a dosage change.
T3 on the other hand is used up within HOURS. And usually peaks in it's blood level about 4 HOURS after taking the medication.
Therefore you can now see why spliting the dose into two doses a day would be a good thing. It stops the single huge BLAST of T3 and breaks it down into to smaller bumps. With the 2nd dose coming on about as the first dose of T3 starts to wear off.
Snice the T4 takes several WEEKS to stabalize, taking half the dose twice a day has almost zero effect on the T4 blood levels with only separating the dose by a few hours compared to several weeks.
Hope this helps to explain what might be going on with you. You get that huge blast of T3 and maybe even a few hours or short time of being maybe even Hyper or approaching it, and then as it wears off throughout the day you feel better in the afternoon. Splitting the dose into two halves and taking the 2nd dose not past about 3PM (so it doesn't mess up your sleep) shoudl help.
If you take it twice a
Are you splitting your meds into two daily doses? If not, it is highly recommended to do so. Half of the dose upon waking, half around lunchtime, if possible keeping it at least an hour apart from food.
In my experience, sometimes the first few days on a new dose can be a little strange, so it may be your body adjusting. Let us know how you feel in 2 or 3 days. If you are still having problems then, you may want to cut back by 1/8 grain and see how your body reacts to that.