Nuclear pharmacy is a specialty area of pharmacy practice dedicated to the compounding and dispensing of radioactive materials for use in nuclear medicine procedures. A specialty area of pharmacy practice is one that requires a concentration of knowledge in a once specific area. The development of nuclear pharmacy as a specialty area followed the development of nuclear medicine as a recognized specialty by the American Medical Association in the early 1970's.
Prior to discussing the field of nuclear pharmacy, it is important to understand some background regarding radioactivity and how it is used in patients. Most people hear the word radiation, and immediately have an image of danger or injury. However, most people do not realize that there is radiation in everyone's lives in many different forms. Electromagnetic radiation is emitted from the sun, from signals sent from radio and TV stations, from radar used to track airplanes, and even visible light. In this particular field, we are interested in a type of radiation termed radionuclides. A radionuclide is an atom that has an unstable nucleus. Recalling chemistry, the nucleus of an atom consists of protons and neutrons. If a nucleus, for whatever reason, has an excess of either one of these constituents, it will try to "get rid of" the excess component and return to a stable state. By doing so, the atom is said to give off this energy in the form of radiation. There are quite a few naturally occurring radionuclides. Any nuclide with an atomic number greater than 83 is radioactive. An atom's atomic number is simply the total number of protons found in the nucleus. There are also many naturally occurring radionuclides with lower atomic numbers.
As nuclear medicine procedures became more widely used, the need for someone to prepare the labeled products for administration to the patients became more evident. While many large hospitals were able to use pharmacists with training in the handling of radioactive material, smaller hospitals were unable to utilize nuclear medicine procedures because they did not have the staff to prepare the necessary doses in a cost effective manner. As a result, in the early 1970's, the concept of centralized nuclear pharmacies was born. When developed, the centralized nuclear pharmacy served as the "drugstore" for the nuclear medicine department. When a particular radioactive material was needed, a trained nuclear pharmacist was available to prepare the product and dispense it to the end user. When you look at a nuclear pharmacy, its operation is not much different than that of a traditional pharmacy - a "prescription" for a particular product is presented, and the nuclear pharmacist must prepare and dispense that "prescription". Where a traditional pharmacist will dispense doses in milligram weight units, a nuclear pharmacist will dispense in millicurie activity units. Where a traditional pharmacist dispenses tablets and capsules, a nuclear pharmacist dispenses the radioactive material in liquid or capsule form. Where a traditional pharmacist will generally dispense the prescription to the patient, the nuclear pharmacist will dispense to a hospital or clinic nuclear medicine department where the dose will be administered to the patient. In general however, the 2 branches of pharmacy are strikingly similar.
Generation of Radiopharmaceuticals
In the production of radiopharmaceuticals, nuclear pharmacists will often make use of a device for carrying out nuclear reactions known as a cyclotron. The cyclotron accelerates charged particles, including protons and deuterons, in a vacuum.
When accelerated, the particles gain energy and velocity under the influence of a magnetic field. These high-energy particles are then directed toward a stable element, enabling nuclear reactions and transformations to occur. Through proper use of the cyclotron, it is possible to produce radioactive drugs in a safe manner.
Nuclear pharmacists also produce radioactive drugs with a radionuclide generator. The generator contains a long-lived nuclide that undergoes decay over time. In the process of decay, the long-lived nuclide forms short-lived daughter nuclides, which are often used in imaging procedures. The short half-life of these imaging agents reduce radiation exposure to patients, but also make storage and transport of the radioactive imaging agents difficult.
Radionuclide generators make it possible to produce short-lived radionuclides in or near the institution where they are used. Using the generator requires careful sanitary procedures, including autoclaving and use of bacteriostatic agents. In addition, all equipment is subject to stringent recordkeeping requirements and regular quality testing.
Staff working in nuclear pharmacies require extensive training on aspects of good manufacturing practice, radiation safety concerns and aseptic dispensing. In the United States an authorised nuclear pharmacist must be a fully qualified pharmacist with evidence of additional training and qualification in nuclear pharmacy practice. Several European Union directives cover radiopharmaceuticals as a special group of medicines, reflecting the wide range of types of producers and staff groups that may be involved. In the UK qualified pharmacists may be involved along with clinical scientists or technologists, with relevant training.
By Garibli A.