What are the guidelines regarding oxycontin and therapeutic massage?

I'm a recent graduate of massage school and would like someone to give me information regarding oxycontin and massage. Is there a certain time massage would be safer for clients using this medication. Are there any reference materials you would recommend regarding medications and massage?
Also this particular client has 4 herniated disks. I am a little nervous about working on her. Any info is greatly appreciated!

: http://alcoholdrugstreatment.info/what-are-the-guidelines-regarding-oxycontin-and-therapeutic-massage