Displaying 2 results of Pyrimethamine Stable Isotopes Pyrimethamine stable isotopes are non-radioactive forms of pyrimethamine, a drug commonly used to treat and prevent malaria. These isotopes have identical chemical and physical properties to the naturally occurring form of pyrimethamine, but with a different number of neutrons in their atomic nuclei. They are used in research and medical applications to study the pharmacokinetics and metabolism of pyrimethamine, as well as to develop more targeted and effective therapies for malaria and other infectious diseases.