ABSTRACT
Depressive illness also called affective disorder occurs either when the depressed state has no apparent cause or reason or when the period of depression is prolonged beyond what is considered normal, with no signs of recovery. Protein kinase C (PKC) inhibitors applied to platelets from depressed patients causes a reduction of calcium in unipolar depression but not in bipolar disorder, supporting the notion that these are distinct disorders with different pathologies. Serotonin syndrome is a potentially life-threatening adverse drug reaction in which excessive serotonin is produced in the brain and leaks into the blood. In dysthymic disorder, there is less evidence for the involvement of the hypothalamopituitaryadrenal (HPA), but there are indications of dysfunction of the hypothalamus pituitary thyroid (HPT) axis causing thyroid hormones abnormalities in many cases. Depression is frequently associated with hypothyroidism, and thyroid hormone is given to a number of depressed patients along with their antidepressant medication.
