Intrathecal Application of Baclofen in the Treatment of Spasticity

Summary

Baclofen, a derivative of g-aminobutyric acid (GABA) has been known for many years to be a useful drug in the treatment of spinal spasticity. However, when the spasticity is severe, the systemic administration has to be increased, often without therapeutic effects but frequently with central side-effects. Baclofen given intrathecally however, in microgram doses has been previously reported to be effective and safe.

A personal experience is reported of 9 severely spastic patients residing in chronic care facilities who were treated from July 1984 to March 1986 with intrathecal baclofen. The spasticity was causing significant nursing care problems, and 6 patients were reduced to a completely bedridden state. Each patient initially received a percutaneous intrathecal drug injection of 0.2–0.7 mg of baclofen to test its efficacy. A subcutaneous intrathecal system for further injections was placed in 6 patients. In 3 patients a decreased level of consciousness was observed. In the 3 cases of multiple sclerosis, intrathecal baclofen resulted in significant reduction of spasticity for 24 to 48 hours after each injection. The spasticity was improved in only one of the 2 cases of posttraumatic paraplegia. The effect was not convincing in the 2 cases of spinal cord tumour, and in the case of cerebral palsy the effect was improvement in spasticity, but also significant drowsiness.

Baclofen, in comparison with some other drugs such as morphine or midazolam, also tried intrathecally by the authors, is the most effective in reducing spasticity. Its use however warrants caution, for it can cause decreased consciousness, and there is currently no antagonist.