Prolactin Explained: What It Does, Signs of Imbalance & Simple Tips

Ever heard the word prolactin and wondered what it actually means for your body? It’s a hormone that most people only hear about when they’re trying to get pregnant or dealing with unexpected milk flow. But prolactin does more than that – it’s involved in hormone balance, stress response, and even your immune system.

In short, prolactin is made by the pituitary gland, a tiny organ at the base of your brain. Its main job is to tell the breast tissue to make milk after childbirth. When you’re not pregnant, your body keeps prolactin at low levels so it doesn’t trigger milk production. Anything that pushes those levels up or down can cause symptoms you might not expect.

When Prolactin Is Too High

High prolactin, also called hyperprolactinemia, can happen for several reasons. The most common cause is a non‑cancerous pituitary tumor called a prolactinoma. Certain medications – especially antipsychotics, antidepressants, and high‑dose birth control – can also raise prolactin. Stress, low thyroid function, and even chest wall irritation (like a tight bra) are lesser‑known triggers.

Symptoms vary by gender but often include:

• Unexpected milk leakage from the breasts (galactorrhea)
• Irregular periods or no periods at all (amenorrhea)
• Reduced libido or erectile problems
• Headaches or vision changes if a tumor is pressing on nearby nerves

When Prolactin Is Too Low

Low prolactin isn’t discussed as often, but it can still cause issues. It usually shows up after severe stress, excessive alcohol use, or as a side effect of certain dopamine‑boosting drugs. Low levels can make it hard for new mothers to produce enough milk, and they might also feel more fatigue or have a weaker immune response.

Because low prolactin often flies under the radar, doctors typically only test for it when you have trouble breastfeeding or unexplained hormonal symptoms.

How to Test & Manage Prolactin Levels

Testing is straightforward: a blood draw in the morning, when prolactin is at its highest, gives a reliable reading. If the result is abnormal, your doctor may order an MRI to check for a pituitary tumor.

Treatment depends on the cause. For prolactinomas, medication called dopamine agonists (like bromocriptine or cabergoline) can shrink the tumor and lower hormone levels. If a medication you’re taking raises prolactin, a switch to an alternative may help. Lifestyle changes – reducing stress, getting enough sleep, and moderating alcohol – also support normal levels.

For low prolactin, the focus is on addressing the underlying stressors or adjusting medications that suppress dopamine. In breastfeeding moms, frequent nursing or pumping can naturally stimulate prolactin production.

Bottom line: prolactin is a small hormone with a big impact. Knowing the signs of imbalance, getting a quick blood test, and working with your doctor can keep it in check. Whether you’re dealing with unexpected milk flow, missed periods, or just curious about your hormone health, a quick prolactin check can save you time and worry.