High Prolactin level in the blood can occur due to a variety of reasons. First let me explain what is Prolactin and what is its normal function.

What is Prolactin?

Prolactin is one of several hormones, produced by the pituitary gland. Prolactin secretion has a circadian rhythm: its level is highest during sleep at night and lowest around noon time.

Secretion of prolactin takes place in pulses, usually separated by about 90 minutes.

What is the normal function of Prolactin?

The main normal function of prolactin is during and after pregnancy. During pregnancy, It is produced in large amounts and is responsible for lactation after delivery.

Prolactin also causes lack of mense during pregnancy and for a number of months after delivery.

High Prolactin – Hyperprolactinemia

A high prolactin is also called hyperprolactinemia.

Causes of a High Prolactin

When someone is found to have a high prolactin level on a blood testing, usually physicians ( especially in the USA ) have a knee jerk reflex of ordering MRI sacn of the brain to rukle out pituitary tumor. Because they don’t want to miss the diagnosis of a tumor for fear of litigation. This mind set often results in unnecessary MRI scans of the brain. This kind of practice may actually miss the real cause of elevated prolactin level such as drugs.

Here is a list of the common causes of a high prolactin level in the blood:

Stress
Breast stimulation
Orgasm
Pregnancy
Hypothyroidism (underactive thyroid)
Drugs such as estrogen( oral contraceptives), metoclopramide ( brand name, Reglan ),domperidone, verapamil, methydopa, reserpine, cimetidine (as intravenous), narcotics and many anti-depressants and anti-psychotic drugs.
Liver disease
kidney failure
Chest wall pain
Spinal cord lesions
Pituitary tumor
Other Pituitary/hypothalamic diseases such as acromegaly, Cushing’s disease, sarcoidosis, metastases, tuberculosis,hemochromatosis, meningioma, head trauma, empty sella.
Radiation to skull

High Prolactin is not always due to a medical disorder

Mildly high prolactin can occur due to a number of normal conditions:

On your annual examination, your physician gives you a thorough breast examination and then nurse comes in and draws your blood for prolactin. Breast stimulation from the breast examination can result in mild elevation in prolactin level.
Having sexual intercourse before the blood draw can also cause a mild elevation in your prolactin level.
Stress causes a mild elevation in prolactin level.
Slight elevation in prolactin level often takes place in the afternoon. Therefore, prolactin level should be drawn in a fasting state.

Normal prolactin blood level is less than 20 ng/ml.

A mild elevation such 20-40 ng/ml may be due to a peak of a pulse or due to stress or breast stimulation. Therefore, in these cases of slight elevation in prolactin, three levels of prolactin should drawn on three separate days to confirm the diagnosis of a true elevation in prolactin level due to a pathological reason.

Diagnostic Tests of High Prolactin

Once a firm diagnosis of high prolactin level has been made, next step is to find out its cause.

A step-by-step approach is important, with special emphasis to rule out pregnancy, drugs and hypothyroidism. Then an MRI of the pituitary area should be obtained in appropriate cases to evaluate for the possible pituitary pathology.

You should see an endocrinologist for the proper diagnostic work-up of the high prolactin level.

Treatment of High Prolactin

Treatment of high prolactin obviously depend upon the cause.

For high prolactin level due to a pituitary tumor, three treatment modalities are available:

Drugs
Surgery
Radiation

Drugs are the treatment of choice In most cases, . These drugs are: Bromocriptine ( brand name, Parlodel) and Cabergoline ( brand name, Dostinex).