Dostinex (cabergoline) reduces elevated levels of the hormone prolactin, either when caused by a prolactinoma (a non-cancerous tumor on the pituitary gland) or when the cause of the elevated levels is unknown.

The condition is most common in women under age 50, but both men and women of any age may develop elevated levels of prolactin in the blood for a variety of reasons.

Dostinex is very effective at lowering prolactin levels, which reverses symptoms. If a prolactinoma is present, the medication will also shrink the tumor in about 90 percent of patients, eliminating the need for surgery.

Managing Prolactin Levels

In short, high levels of prolactin interferes with the production of estrogen in the ovaries of women, or the production of testosterone in the testes of men. The most noticeable symptoms are those of low estrogen or testosterone, though post-menopausal women may not notice any symptoms, as the ovaries have already stopped producing estrogen. Symptoms include:

In women:

• Unexplained breast milk production
• Missed or erratic periods
• Difficulty becoming pregnant
• Hot flashes

In men:

• Enlarged breasts
• Loss of libido
• Impotence
• Fatigue
• Loss of muscle mass

Large prolactinomas, called macroadenomas, may cause additional symptoms in both sexes due to pressure on surrounding tissues:

• Vision changes
• Underactive thyroid function
• Underactive Adrenal glands
• Headaches

Once elevated levels of prolactin are discovered, treatment typically starts with the lowest possible dose and is gradually increased if needed:

• Take 0.25 mg twice per week for 4 weeks.
• If improvements are not seen after 4 weeks, take 0.50 mg twice per week for 4 weeks.
• Continue increasing each dose by 0.25 mg every 4 weeks until improvements are noticed or until reaching 1 mg per dose (2 mg per week).
• Do not exceed 2 mg per week without explicit doctor instruction.

If the dose is sufficient, symptoms should noticeably improve within 2 to 3 weeks, sometimes within days. It may take several months for tumors to shrink, even if symptoms are greatly improved. Regular doctor checkups are important to ensure Dostinex is continuing to work.

Treatment typically continues for some time after successfully reducing prolactin levels or shrinking a prolactinoma; months or even years. It is not unusual for Dostinex treatment to be periodically stopped to see how the body manages on its own; treatment may be reinstated if prolactin levels begin to rise again.

Adverse Effects

Patients with certain preexisting conditions should use extra caution if taking Dostinex, and do so only with doctor approval:

• Parkinson disease
• High blood pressure
• Liver or heart valve disease
• Pulmonary, pericardial, or retroperitoneal fibrosis

The most common side effects associated with Dostinex are gastrointestinal, such as:

• Gas
• Nausea
• Vomiting
• Constipation
• Mild stomach cramps

These symptoms usually disappear entirely after a week or two of treatment, though they may briefly resurface if dosage is increased. If severe or persistent, a doctor or pharmacist may be able to recommend treatments to manage individual side effects; otherwise alternative therapies may need to be explored.

Very rarely more serious side effects are encountered while using Dostinex, which should be brought to the attention of a doctor before continuing treatment with Dostinex:

• Difficulty breathing
• Persistent coughing
• Severe fatigue
• Mood swings
• Breast pain
• Edema

The medication is unlikely to harm unborn or nursing babies, however parents should discuss possible risks with a trusted doctor before use. There may be better alternative treatments available for women who are actively trying to become pregnant.

Dostinex is derived from ergot and should not be used by individuals with a history of allergic reactions to ergot products.

The medication causes dizziness, light-headedness, and mental "fogginess" in some individuals, which may make it difficult to perform complex or dangerous tasks. Use with caution until the effects are known.