Often when you are sick you just need a boost of Vitamin C, fish oils, or probiotics along with herbs, but sometimes a compromised Immune system is related to stress, fatigue, lowered adrenal and thyroid function. A sluggish immune can be boosted with the proper use of herbs like astragalus, or reishi mushrooms. When stress is elevated long term the immune is often lowered and eventually the adrenals and thyroid can suffer. At this point, some adrenal-helping herbs can be utilized as well as vitamins which contain glandulars to help rebuild adrenal tissue. If the adrenals are dealing with long term stress and releasing too much cortisol this can inhibit the conversion in the thyroid of T4 to the more active T3 and possibly lead to hypothyroidism. The excess cortisol can also lead to excess secretion of “reverse” T3 which also inhibits T3.