The first time I took Avinza (a single 30mg capsule) I felt nauseas (I don't know how to spell it) for 20 minutes or so, then I felt really high for the next hour, but I had never taken Morphine before so that was expected.
With a short acting Morphine, you're supposed to take it every 4-6 hours from what I've found - my Dr. gave it for breakthrough with a 4-6 hour dosing reccomendation. If that holds true, then a 30mg supposed 24 hour formula should go on the same principle, but I'm not exactly sure and I haven't seen any testing/research on this.
If it did go by a 4 hour release schedule, then that 30mg would be 5mg every 4 hours (there are six four hour periods in a day, so 30/6 = 5).
On the other hand, if it went by 6 hours, then it would be 7.5 every 6 (there are four six hour periods, so 30/4 = 7.5). It would also mean that the first dose would release immediately.
That's just specualtion on my part. My Dr made a comment that 9 to 10% of the dose releases right away, but that throws off any "evenness" for the rest of the doses.
I take 120mg a day now: I went from 30 to 60 after a few months, then from 60 to 90 a few months later. After being on 90 for 3 years, I moved to 120 this past April. I love Avinza! It still makes me high sometimes (I get super relaxed and can't stop talking), but the pain relief is superb, leaving me at a 3-4 on most days. Unfortunately I still have bad days with 6-8 pain, but they're rare (they come with neck pain).