Yeah, well i can't say i'm not an addict.
90mg a day could well be heading towards a tolerance and upping the dose etc.
Have you looked into some of the NSAIDs. Naproxen(aleve) is very decent non-opiate pain medication.
Also Torodol and tramadol, while being opioid's, are non-narcotic pain killers. Perhaps you could consider breaking up your codeine to say 1 day codeine, 1 day Naproxen, 1 day tramadol - repeat.
I don't really think 90mg a day is troubling, however, undoubtedly you will get tolerance and its analgesic effects will diminish causing you to up the dose. So perhaps consider some other NSAID's. Depending on what pain you are suffering.
Nabumetone commonly known under the brand name Relafen is used a lot in arthritic pain or hormonal pain.
Celecoxib, also known as Celebrex, Celebra or Onsenal. It is used with Rheumatoid Arthritis, Osteoarthritis, Acute Pain and extreme menstrual pain.
Oxaprozinum/Oxaprozin - Daypro, Dayrun, Duraprox. Is used also in Arthritic patients for joint pain.
These are all Non-steroidal Anti Inflammatory drugs, so they work mainly to reduce inflammation (apart from tramadol and torodol).
Maybe have a talk with your doctor about all the non-opioid/opiate pain killer options. I would by all means keep the Codeine, but perhaps as I said break it up with other pain killers.