Hello, Oxycodone, oxycontin, morphine sulfate are all from the same class of drugs called opioids with almost the same severity in pain control and with similar side effects. You can take any among all of it. The only difference between them is their onset of action and duration. IR means immediate release and ER means extended-release. These are best analgesics for severe pain. You can increase dose after consulting your primary physician or if not, the next option for you will be to go for nerve block therapy (in which painful nerves are blocked by anesthetic drugs). Hope I have answered your query. Let me know if I can assist you further. Take care Regards, Dr Muhammad Faisal Bacha, Internal Medicine Specialist