Oxycodone does not contain codeine but it belongs to the same as codeine i. e. opioid. Basically you are allergic to codeine. So there is a possibility that you may be allergic to oxycodone also or other opioid pain killer. Second time exposure to codeine might cause anaphylactic reaction which is a life-threatening reaction. Advice 1. Do not take oxycodone 2. Tell your doctor that you are allergic to codeine 3. You can take over the counter ibuprofen 600 mg plus paracetamol 500 mg combination after meal for pain relief 4. Add Ranitidine 150 mg every 12 hours along with ibuprofen/paracetamol combination to avoid gastric irritation 5. Keep a note or card in your pocket every time mentioning that you are allergic to codeine and opioid pain killer. It sometimes helps in emergency 6. Immediately go to hospital if you have any sign of anaphylaxis such as breathing difficulty, low blood pressure, nausea/vomiting, throat constriction, unconsciousness after taking any opioid pain killer etc Thanks