A case of very long-term appearing drug tolerance to intrathecal baclofen.

A 66-year-old man affected by familial spastic paraplegia since he was 22 developed drug tolerance to intrathecal baclofen after 16 years of treatment A stable dosage of 850 microg/day, achieved after the first two years, appeared to be progressively inadeguate to relief his spasticity. No other evidence of additional diseases or progression of his neurological disease were recognized. The daily dosage was then increased to 1200 microg/day without any decrease in spasticity or improvement in the patient's motor performance. Thus a slow and progressive decrease of the daily dosage was performer by 10% each 15 days while the patient's clinical condition was monitored. The patient reached a complete withdrawal of the baclofen administration experiencing the same spasticity and motor performance he experienced at the beginning of his therapy with intrathecal baclofen in 1991. The patient was then kept on drug holiday for three months without any variation in his clinical picture. A stabilized daily baclofen dosage of 250 microg was then reached to maintain the same improvement of motor performance that the patient had experienced before the onset of drug-tolerance signs. Some cases of drug tolerance to intrathecal baclofen were previously reported but this is an original case of very long-term onset of this phenomenon.