Hello, thankyou for approaching DoctorSpring with your query.
Oxycodone is a semi-synthetic opiod. It has to be taken with care. It is usually used for acute periods of severe pain in case of herniated disc to control the pain(as in your case). Continue the drug till your surgery and the doctor will slowly decrease your dose and take you off it.

The reason of surgery is to give you symptomatic relief, so you will be able to be off the drug. In case of pain the doctor may put you on a NSAID drug for the control of pain.

Oxycodone is known to cause dry mouth as it is an opiod. Frequent sips of water will help you feel better. Just as a precaution let me mention that the drug dosage should be taken in consultation with your doctor and shouldn't be altered on your own.

I wish you all the best for your surgery. And you can follow up with any further query.

Thanks