This is an excellent question, and I'm glad you asked it.
Neither hydrocodone nor oxycodone contain codeine, per se. However, all of these drugs belong to a class called opioids. This means they share certain characteristics, namely they're all narcotics that work on opioid receptors throughout the body to block pain messages from reaching the brain. This reduces our feeling of pain.
Most of my patients who were sensitive to codeine, specifically, were able to tolerate the "codone" family of medications quite well. If you find you have intolerable adverse reactions (such as vomiting) to either hydrocodone or oxycodone, notify your health care provider. There are plenty of pain medications to choose from. Your provider can help you find one that works for you.
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