Displaying 1 results of Amifampridine Stable Isotopes Amifampridine Stable Isotopes are non-radioactive forms of the drug Amifampridine, which is used to treat a rare neuromuscular disorder called Lambert-Eaton myasthenic syndrome. These stable isotopes have the same chemical and physical properties as the naturally occurring Amifampridine, but are less hazardous to handle and can be used for research and development of new treatments for the disorder.