What is Prolactin?
Prolactin is a hormone that your pituitary gland produces and sits at the bottom of the brain. Prolactin causes breasts to grow and develop and causes milk after the birth of a baby. Both men and women typically have small amounts of prolactin in their blood. Other hormones, called prolactin-inhibiting factors (PIFs), such as dopamine, control the prolactin levels. Prolactin levels go up during pregnancy. There is an abrupt drop in estrogen and progesterone after the baby is born. High levels of prolactin trigger the body to make breast milk. Prolactin helps regulate the menstrual cycle (periods) in females who are not pregnant.
What constitutes hyperprolactinemia?
Hyperprolactinemia is a condition of excessive prolactin in the blood of non-pregnant women, and in men. Hyperprolactinemia, in women, is relatively common. Approximately a third of women with irregular periods in their childbearing years but normal ovaries have hyperprolactinemia. A woman may have trouble getting pregnant when this happens or her breasts may start producing milk outside of pregnancy (galactorrhea). Ninety percent of galactorrhea women also suffer from hyperprolactinemia. High levels of prolactin interfere with other hormones, such as estrogen and progesterone, to normal production. That may change or stop ovulation (the release of an ovary egg). It may also lead to periods that are irregular or missed. Some women have high levels of prolactin, with no symptoms.
High levels of prolactin in men can cause galactorrhea, impotence (incapacity to get an erection during sex), reduced sexual desire, and infertility. A man suffering from untreated hyperprolactinemia may produce less sperm or no sperm.
What are the common causes of hyperprolactinemia?
Some common causes are:
- Hypophyseal tumors (prolactinomas)
- Hypothyroidism (thyroid deficiency)
- Medicines are given for depression, psychosis, and hypertension
- Herbs including fenugreek, red clover, and fennel seed
- Chest wall irritation (from surgical scars, shingles, or even a too-tightened bra)
- Stress or (usually excessive or extreme) exercise;
- Some foods
- Stimulus Nipple
How do you test for hyperprolactinemia?
Blood tests can measure prolactin levels. Sometimes the levels are higher if you’ve been eating recently or are under stress. After you’ve fasted and relaxed the test may be done again. Your doctor may also do a physical examination to find any obvious causes or breast discharge.
If after the second check the levels are still high, your doctor may order a brain magnetic resonance imaging ( MRI) scan to check for pituitary gland tumors.
How is hyperprolactinemia treated?
The treatment is causal dependent. If no cause is found, or you have a pituitary gland tumor, medicine is the usual treatment. Hypothyroidism is treated with thyroid replacement medicine which should also bring back normal levels of prolactin. If your regular medicine is the reason for your high levels of prolactin, your doctor will work with you to find a different medicine, or add one to help lower your levels of prolactin.
Medications used for treating hyperprolactinemia
Cabergoline and bromocriptine are the most widely used medications. Your doctor will start you on a low dose of one of these medications and increase the dose slowly until your levels of prolactin return to normal. The treatment goes on until your symptoms diminish or you become pregnant.
Cabergoline is taken twice a week with fewer side effects compared with bromocriptine. Cabergoline typically drops prolactin levels faster to normal than bromocriptine. When taken in high doses, cabergoline may cause heart valve problems but these doses are not used in women who try to get pregnant.
When a woman is pregnant, bromocriptine and cabergoline may be used. Lightheadedness, nausea, and headache are the most common side-effects. Adding the dose slowly helps with side effects. Another way of diminishing side effects is to give bromocriptine directly in the vagina in a suppository. This is the use of medicine off-label.