Psychiatric disturbances and central nervous system (CNS): Altogether 51 percent of patients were affected. Very frequent: Sleep disturbances (somnolence 18%, insomnia 11%), vertigo (27%), and depression (13%). Frequent: dyskinesia (4%) and hallucinations (4%). Cardiovascular: Approximately 30 percent of patients experienced side effects. Most frequent were hypotension (10%), peripheral edema (14%) and non-specific edema (2%). Arrhythmias were encountered in 4.8%, palpitations in 4.3%, and angina pectoris in 1.4%.In a combination study with 2,000 patients also treated with levodopa, the incidence and severity of side effects was comparable to monotherapy. Encountered side effects required a termination of cabergoline treatment in 15% of patients. Additional side effects were infrequent cases of hematological side effects, and an occasional increase in liver enzymes or serum creatinine without signs or symptoms. As with other ergot derivatives, pleuritis, exudative pleura disease, pleura fibrosis, lung fibrosis, and pericarditis are seen. These side effects are noted in less than 2% of patients. They require immediate termination of treatment. Clinical improvement and normalization of X-ray findings are normally seen soon after cabergoline withdrawal. It appears that the dose typically used for treatment of hyperprolactinemia is too low to cause this type of side effects. Valvular heart disease
In two studies published in the New England Journal of Medicine on January 4, 2007, cabergoline was implicated along with pergolide in causing valvular heart disease. As a result of this, the FDA removed pergolide from the U.S. market on March 29, 2007.
It also has been suggested that it has a possible recreational use in reducing or eliminating the male refractory period, thereby  allowing men to experience multiple ejaculatory orgasms in rapid succession, and at least two scientific studies support those speculations. : e28–e33  Additionally, a systematic review and meta-analysis concluded that prophylactic treatment with cabergoline reduces the incidence, but not the severity, of ovarian hyperstimulation syndrome (OHSS), without compromising pregnancy outcomes, in females undergoing stimulated cycles of in vitro fertilization (IVF). Also, a study on rats found that cabergoline reduces voluntary alcohol consumption, possibly by increasing GDNF expression in the ventral tegmental area. It may be used in the treatment of restless legs syndrome. Pregnancy and lactation
Relatively little is known about the effects of this medication during pregnancy and lactation. In some cases the related bromocriptine may be an alternative when pregnancy is expected. Pregnancy: available preliminary data indicates a somewhat increased rate of congenital abnormalities in patients who became pregnant while treated with cabergoline.. However, one study concluded that "foetal exposure to cabergoline through early pregnancy does not induce any increase in the risk of miscarriage or foetal malformation." Lactation: In rats cabergoline was found in the maternal milk. Since it is not known if this effect also occurs in humans, breastfeeding is usually not recommended if/when treatment with cabergoline is necessary. Lactation suppression: In some countries cabergoline (Dostinex) is sometimes used as a lactation suppressant. It is also used in veterinary medicine to treat false pregnancy in dogs.