You need to establish the pathology of why you have low metabolic rate in the first place. The reasons I see commonly with this imbalance is nutritional deficiency such as iron, copper, magnesium, zinc, selenium and especially iodine, adrenal imbalances, toxicity which may be causing the mitochondrion not being able to respond to thyroid hormone due to depletion of glutathione from heavy metals and metals also binding to the receptor blocking the thyroid from being active. The body will slow down metabolism in order to conserve energy for a reason. The last thing one wants to do is going to adding thyroid into an already toxic environment. This is why I ascertain state of the mitochondrion as well as heavy metal or toxic load and the body's genetic ability to detoxify properly before even suggesting thyroid hormone to Dr
Would you step on the gas why sitting in the car with your garage door down? This is the same principle people are doing when taking thyroid in a toxic state !!