Prolactin blockers

Prolactin blockers — are pharmacological agents used to lower the level of prolactin in the blood.

Prolactin is a peptide hormone produced by the anterior pituitary gland and performs many more functions than just participating in lactation. It affects the reproductive system, menstrual cycle, fertility, metabolism, immune responses, and the body’s adaptation to stress.

Therefore, intervening in its regulation always affects several physiological systems at once.

How prolactin blockers work

The secretion of prolactin is under constant inhibitory control by dopamine. In clinical practice, prolactin blockers are medications that mimic the action of dopamine and activate D2 receptors on lactotrophic cells of the pituitary gland. As a result, the synthesis and release of prolactin decrease, and its concentration in the blood gradually normalizes.

The therapeutic effect manifests in the restoration of the menstrual cycle, resumption of ovulation, reduction or disappearance of galactorrhea, as well as a decrease in the size of prolactinomas when present. Medications in this group are used strictly according to medical indications and require regular laboratory and clinical monitoring.

Main medications

• cabergoline — a D2 receptor agonist with a prolonged effect, most commonly used for hyperprolactinemia and prolactinomas;
• bromocriptine — an older generation drug that also stimulates dopamine receptors but is more often accompanied by side effects;
• other dopamine agonists — used less frequently and selected individually depending on the diagnosis and tolerance.

Indications for use

The prescription of prolactin blockers is justified in conditions accompanied by persistent elevation of the hormone and clinical manifestations:

• hyperprolactinemia of various origins;
• pituitary prolactinomas;
• galactorrhea outside of pregnancy and lactation;
• menstrual cycle and ovulation disorders;
• infertility associated with elevated prolactin.

Side effects and limitations

Since the medications affect the dopaminergic system, they can cause systemic reactions. The most common side effects include nausea, dizziness, low blood pressure, weakness, and headaches. Some patients report mood changes, decreased libido, muscle pain, and dry mouth.

During prolonged therapy, it is important to monitor prolactin levels, the overall hormonal profile, and the condition of the cardiovascular system. In cases of prolactinomas, additional ophthalmological monitoring is conducted to assess visual fields.

Practical recommendations

1. do not start or stop taking medications without consulting a doctor;
2. regularly monitor prolactin levels and associated hormones;
3. inform the doctor about any changes in well-being, mood, or blood pressure;
4. discuss changes in diet and activity levels during prolonged therapy.

Prolactin blockers are an effective medical tool for clearly defined indications. Their task is to eliminate the consequences of hormonal imbalance, not to address the root causes, such as tumor processes, medication effects, chronic stress, or energy deficiency. A competent combination of therapy, nutrition, and lifestyle allows for achieving stable and safe results.