A blood test for prolactin after a meal will not have any effect on the results and fasting is not required for this test. Prolactin, also called prolactin, is a peptide hormone secreted by prolactin cells in the anterior pituitary gland. If prolactin levels are significantly elevated, it may cause a woman to experience irregular menstruation, infertility, breast overflow, and changes in sexual function. If a woman experiences these symptoms, a blood test for prolactin is usually necessary. To check prolactin, it is not necessary to draw fasting blood, and eating or drinking water will have little effect on the results. However, the day before the test, to ensure sufficient rest, do not drink alcohol, do not blindly use drugs, the second day to the hospital to rest half an hour before the blood test. There are many reasons for high prolactin, such as hypothalamic disease, pituitary disease, primary hypothyroidism, polycystic ovary syndrome and so on. Long-term use of antidepressants, antiepileptics, antipsychotics, and antihypertensives may also increase prolactin levels.