Hypothyroidism caused by decreased thyroid hormone in pituitary gland increases thyroid-releasing hormone production, which in turn leads to increased prolactin levels and causes galactorrhea.21Correction of hypothyroidism with levothyroxine administration leads to normalization of serum prolactin levels.22Dopaminergic antidepressant drugs may also lead to galactorrhea as they work as dopamine antagonists.1Peripheral stimulation, such as chest wall irritation, nipple and mammary gland manipulation, and estrogen and progesterone hormone intake, also increases prolactin blood level. This evidence concerns the gene PRL and Galactorrhea.