BROOKLYN - There is a growing demand for tougher penalties for those selling K2, or synthetic marijuana.

So far this year, 15 people have died from synthetic marijuana use in the United States. There have been no deaths in New York.

The state Health Department says there have been 10 times as many emergency room visits between June and August because of K2 as compared to last year.

Former users say the side effects include sedation, increased heart rate, hallucination, paranoia, anxiety, vomiting, high blood pressure and violence.

State Sen. Jeff Klein's bill would make selling more than 25 grams of the drug a felony punishable by up to five years in prison.

There is also a call to add synthetic marijuana to the controlled substance list.