There are lots of things that must be considered when deciding whether to increase (or decrease), the first is "do I need more" and the next "can I tolerate more".
We encorage people to take their resting pulse regularly and graph temperatures, as per Dr Rind if you are in doubt about adrenals (see below). If you are happy about adrenals then keep taking temperatures on waking if monitoring thyroid levels. Recording these together with how you feel at the time helps you decide if an increase is needed.
Most people who are not "fit athletes" feel best with a pulse somewhere between 75 and 90 per minute. Feeling the pulse on your wrist and counting them for 15 seconds is the easiest way to do this, just multiply the reading by 4 and you have the number of pulses in a minute.
As you increase dose you will have times when you are feeling well, reccord the pulse you had then and how you felt. If you are feeling a bit off and wondering if you need an increase, or just overdid things with your new found energy and enthusiasm with life, then take your resting pulse again. If it's sunk below your "sweet spot" then you probably need an increase.
If you are feeling a bit "wired" and wondering if you arre taking too much then again take your pulse, if it's above your "sweet spot" something is off balance, it may be too much T3 (a raised temperature will help confirm this) or it may be low sodium, see the salt water test.
The chemical reactions in the human body are extremely temperature sensitive and sophisticated temperature regulation mechanisms have evolved to be able to stabilise this. These involve various glands and hormones as well as modulating the blood flow to the extremities and being able to sweat to use evaporative cooling.
Unfortulately this wonderful temperature regulation system that we have can go wrong and either end up unstable or have the wrong "set point".
One of the best ways of making use of temperature as a diagnostic tool for adrenal and thyroid issues is to take temperatures and graph them the way shown in this link. We don't agree with everything the author of that site advocates but are very impressed with his temperature graph.
There are instructions with the graph that show the interpretation of it but basically an unstable average temperature between successive days indicates low adrenals which will need supporting in order to stabilise the temperature before your body will be able to tolerate enough thyroid hormone to raisee your temperature and feel well. This page deals with adrenals. It is critically important to ensure that your temperature is stable BEFORE adding T3 as you will crash badly otherwise.
Your target is an average temperature of 98.6F (37C) with it the same from day to day within 0.2F or 0.1C. Cortisol stabilises temperature, T3 raises it.
The other main thing that prevents the body being able to tolerate enough thyroid hormone to feel well is low Ferritin. The STTM site has a good section on Ferritin and I have linked to it here. In a nutshell Ferritin is storage iron and if it is too low then you can't tolerate enough T3 to feel well. See also our iron pages here (updated 12/12)