Caberlin (cabergoline) is used to inhibit secretion of the hormone prolactin in patients with elevated levels due to a tumor or due to unknown causes.

Excess prolactin production is often caused by a non-cancerous tumor called a prolactinoma on the pituitary gland. If a tumor is present, treatment with Caberlin will also shrink the tumor; this resolves the issue entirely in about 90 percent of patients, though in about 10 percent of patients additional measures---such as surgery or radiation therapy---will be needed.

In unknown causes, Caberlin inhibits the pituitary gland's secretion of prolactin, lowering overall levels.

Symptoms

Prolactin is a naturally-occurring hormone that is important for a healthy, functioning body. However, as with most things, in excess it can cause harm; individuals with elevated prolactin may experience a range of unpleasant, disruptive, and even painful conditions.

The most significant impact of excess prolactin is on reduced levels of estrogen in women and reduced levels of testosterone in men. Symptoms will vary by gender.

In men:

• Lowered testosterone levels
• Enlarged breasts
• Loss of libido
• Impotence
• Fatigue
• Loss of muscle mass

And in women:

• Lowered estrogen levels
• Unexplained breast milk production
• Missed or erratic periods
• Difficulty becoming pregnant
• Hot flashes and other menopause-like symptoms

Note that lowered estrogen/testosterone levels have many causes other than elevated prolactin levels. Likewise many of the above symptoms can have causes that are unrelated to estrogen/testosterone levels. It's important that patients have prolactin levels checked by a doctor prior to starting treatment with Caberlin.

Large prolactinomas---called macroadenomas---may cause additional symptoms in both genders:

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

In most cases Caberlin will help, with symptoms starting to reverse about 2 or 3 weeks after starting treatment. It may take several months before prolactinomas are measurably smaller, and still more time before they're gone completely, but symptoms should begin to improve well before then.

Dosage & Administration

Treatment is typically similar in all patients, though there may be exceptions for patients with macroadenomas. Dosage starts small and, if needed after 3 or 4 weeks of treatment, are incrementally increased:

• Start with 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.

Treatment typically continues for months or even years after successfully reducing prolactin levels or shrinking a prolactinoma. It is not unusual for Caberlin 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.

Precautions

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

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

In most cases, if used as directed, treatment with Caberlin does not produce serious side effects; gas, mild stomach cramps, constipation, and so forth. These usually stop occurring after a few weeks of treatment.

Though rare, unfortunately more serious side effects are sometimes encountered while using Caberlin. If experiencing the following discontinue Caberlin use until discussing them with a doctor:

• 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 doctor before use. There may be better alternative treatments available for women who are actively trying to become pregnant.