Thanks for your query. I understand your frustration with doctors.
The effect of oxycodone
lasts for 3-6 hours.
Since the morning dose does not cover the afternoon hours, I suggest that you consult your doctor, who will either increase the morning dose of oxycodone; or, switch over to an alternative/equally effective but with longer duration of action (12hours).
Hope I have answered your query.
Dr. Rakesh Karanwal