Well, I'm assuming that it just depends on the strength and dosage, and those are determined by your doctor...an average example starting on morphine would be: tablets/capsules/oral solution/suppositories 10 to 30 mg every 4-6 hours. Injection would be 5-20 mg intramuscularly or subcutaneously every 6 hours. After that, the doctor can adjust the dosage to your individual needs (more, less, etc.)