Management of hair loss in women presents several challenges for general practitioners, who are the first in identifying its cause and consequences in everyday clinical practice. It is usually associated with multiple secondary factors, including endocrine disorders, drug side effects, and physical or emotional stress. We report a possible pathophysiological link between hyperprolactinemia and alopecia in a patient with preexisting autoimmune thyroid disease, which has not been documented in a significant number in the literature. A 27-year-old female patient with a previous history of an autoimmune thyroid disease on hormone substitution therapy presented to a family doctor with signs of frontal alopecia that had started several months previously. On examination, frontal alopecia was confirmed. Laboratory results and thyroid ultrasound confirmed autoimmune thyroid disease, with reduced parathyroid hormone and elevated prolactin. Her female sex hormones were in the normal range. Due to elevated prolactin levels, computed tomography of the pituitary gland was performed, which excluded any brain pathology. Based on available data, there is no published systematic analysis on hyperprolactinemia-induced alopecia in previous autoimmune diseases (large cohort studies). This report indicates that, due to moderately elevated prolactin values, consideration of alternative causes and further diagnostics are necessary to exclude a prolactin-producing tumor of the pituitary gland.