Oxycodone 40 mg is indicated only for the management of severe and persistent pain . It's used at that time when the other pain medicines did not work well and the pain could not be tolerated. 40 mg Oxycodone is very strong and a high dose of medicine. It works within 10 to 30 minutes . 40 mg of Oxycodone is used with food or without food . Its common side effects are headache and sleepiness. It's safe but do not misuse it because it's very dangerous after an overdose .