Dostinex Linked to Heart Valve Problems

New York, NYTwo recently published studies have linked Dostinex and Permax to serious heart valve problems, the same problems that were linked to fen-phen in the 1990s. Now, one of the drugs, Permax, has been pulled from the market and Dostinex has a new warning label.

The studies were published in The New England Journal of Medicine. They confirmed earlier studies that showed that using Dostinex increased the risk of heart valve problems in patients with Parkinson's. However, they also showed that the risk is higher than previously thought, and that people who took Dostinex at higher dosages for more prolonged periods were at the highest risk of developing heart valve problems.

The studies showed that risk only in patients with Parkinson's, which is important because patients who take Dostinex for Parkinson's take it at a much higher dosage than those taking the drug for hormone disorders.

A new warning about the risks of Dostinex was added to the labeling but it is only considered precautionary, meaning that there is no black box warning. Furthermore, the warning is not obvious in the prescribing information that is given to doctors.

In an interview with the New York Times, Dr. Bryan L. Roth, a researcher who wrote an article that accompanied the studies, said that the risk of heart valve problems is "extraordinarily high." He also noted that Dostinex caused the same valve damage that was caused by fen-phen back in the 1990s. The link between fen-phen and heart valve damage was serious enough that Pondimin and Redux (components of fen-phen) were both pulled off the market in 1997.

The cause of the heart valve problems is that Dostinex causes cells in the heart valves to multiply. This leads to the valves thickening and being unable to open and close properly. The backflow of blood can lead to heart palpitations and breathing problems. Valve damage can require surgery to fix and, if not caught in time, can lead to heart failure and death.

One of the studies, conducted in Milan, found that 29 percent of patients taking Dostinex had damaged heart valves. That is in comparison with only six percent of patients in the control group, not taking the drug, with damaged heart valves.

Dostinex (known generically as cabergoline), which is made by Pfizer Inc., is a dopamine agonist.. The drug blocks the secretion of prolactin from the pituitary gland. Dostinex is approved in the US for the treatment of disorders related to high levels of prolactin but it is not approved in the US for the treatment of Parkinson's disease.

If you are taking Dostinex and are concerned about the side effects, speak to your doctor to discuss your options.