Codeine and Parkinson's Disease

Morphine is generally not given as morphine through the gastrointestinal tract. Some people don't have the ability to do this metabolism, so therefore they get no analgesic effect from coding. Leaver dopal can't cross it by blood-brain barrier as dopamine. But you can cross it with leaver dopal, which then isn't minimized. People with Parkinson's disease don't produce enough dopamine.