The New York Times said patients seeking treatment for addiction and mental illnesses have for decades faced higher co-payments and deductibles, as well as stricter limits on treatment. Supporters say the new law will help end insurance discrimination, reduce the stigma of mental illness and make it easier for people to obtain treatment for conditions such as depression, autism, schizophrenia, eating disorders and drug abuse.

The law, effective for most plans in 2010, will improve insurance coverage for 113 million people, the newspaper said.