[Long-term administration of large doses of oral morphine for chronic pain]

We here report a patient with chronic pain who was treated with large doses of oral morphine. A 37-year-old female was diagnosed as Lyme disease and lumbar disc hernia. When she received lumbar puncture for myelography, she fainted due to severe pain in the legs. After this incident, her pain increased markedly, and she visited our outpatient clinic in 1996. After confirming the temporary pain relieving effect of caudal block, we prescribed oral morphine tablets 60 mg daily. The dose of morphine necessary to relieve her pain increased gradually to 220 mg. But she did not develop dependence or side effects. However, when the daily dose of 300 mg was administered, she felt dizzy. We therefore performed lumbar sympathetic block with phenol. After the block, her conditions improved markedly at a dosage of 300 mg. In conclusion, our experience in this case has shown the effectiveness of long-term morphine use with non-cancer patients and the efficacy of nerve block to avoid increasing the morphine dosage.