For all practical purposes, this does not distort any information. 4-aminopyridine was used first in the treatment of myasthenia gravis. It's from a family of relatively simple chemicals that bind to potassium ions. The net result of this is that 4-AP will improve nerve conduction. The first attempts were somewhat interesting in that they precipitated serious seizures.
Drugs are generally equal opportunity employers.
The effect is global -i.e in areas where greater conduction is desired and in areas where greater conduction is not desired. This was circa 1988. With such adverse results, there was a new sense of caution. Subsequent work attempted to find a threshold were the positive results could be achieved without the negative effect. Two facts emerged.