MINNEAPOLIS (WCCO) – When the birth control pill “Yaz” became an option, Cassie Bonstrom’s doctor wasn’t concerned about giving her a prescription.

“I’ve never had a problem with it, so I have no reason to switch,” said Bonstrom.

But after a recent FDA study that said the drug puts women at higher risk of blood clots, Bonstrom sees why many women would switch. The Bayer Corporation makes “Yaz,” and the company has not only marketed the drug as birth control, but also as a drug that helps with acne and mood swings.

Problem is, according to this study, the side effects can be deadly.

“I wish I could say I was surprised, but I’m not at all,” said Genevieve Zimmerman of Zimmerman and Reed.

Zimmerman is an attorney who represents more than two dozen women nationally, who she said have been harmed by “Yaz.”

“We are seeing people with blood clots. We have some forming in their legs and traveling up to their lungs forming pulmonary embolism. That can be fatal if it’s not caught and treated quickly and appropriately,” said Zimmerman.

Zimmerman said some clients have had to have their gall bladders removed, and others have reported kidney failure and heart problems.

“It’s not a drug I would take. It’s not a drug I would recommend my friends or family take,” said Zimmerman.

“Yaz” lists many of the potential side effects on the front page of its web site. While every birth control pill can have some side effects, the FDA’s suggestion that Yaz’s could be significantly higher has Bonstrom looking at all her options.

“When other people start saying there could be a problem, it deserves a second glance,” said Bonstrom.

“Yaz” contains a synthetic hormone, which is known to increase potassium levels in the blood. Bayer has yet to comment on the study. This study also cites the Patch from Johnson & Johnson and the Nuvaring from Merck for increasing the risk of blood clots.