Percocet. A combination of narcotic oxycodone and non-narcotic acetaminophen, pro-longed. Use of this drug can reduce the drug’s effectiveness. Side effects include nausea, vomiting, constipation, lightheadedness, dizziness, drowsiness, flushing, vision changes and mental/mood changes. Percocet addiction is one of the more severe opioid addictions because it contains the powerful narcotic called oxycodone.