Marijuana will soon come to the rescue of epileptic children and adults in Illinois under a law signed Sunday, by Governor Pat Quinn.

The medical disorder now joins the list of other conditions that can be legally treated under the state's marijuana program, Senate Bill 2636. will be effective from January and would permit epileptic children to be treated with non-smoking forms of cannabis, as long as they have permission from a parent.

At present, the medical marijuana law permits only Illinois residents 18 years and older to use the drug in a four-year pilot program.

According to the parents of children with epilepsy, consuming the cannabis oil reduces seizures and does not make children feel high. However, those against legalisation of marijuana disagree with further decriminalizing the drug, reports the Associated Press.

In September, residents will be formally allowed to apply for permission to use the drug to treat the medical condition, Quinn spokeswoman Katie Hickey said Sunday.

"This new law will help alleviate the suffering of many adults and children across the state," Quinn said in statement. "Epilepsy is a debilitating condition, and this much-needed relief will help to reduce some of its symptoms for those who endure seizures."

 "I have a 14-year-old constituent by the name of Hugh who lives with epilepsy," said Republican state lawmaker Jim Durkin, who co-sponsored the new law, reports Reuters. "His parents, Bob and Kelly, want to provide their son with as much relief as possible. Unfortunately, traditional medications and methods have not worked."

Last week, a state committee that supervised rule-making for Illinois' budding medical marijuana plans approved of the move.

Other states that have decriminalized marijuana for recreational purposes are Colorado and Washington.