Radio Pharmacy Overview

Radio Pharmacy/Nuclear Pharmacy

• Radio pharmacy is the specialty practice of pharmacy focusing on the safe and effective use of radioactive drugs, also known as radiopharmaceuticals (WHO).
• Radiopharmaceuticals are medicinal formulations with radioisotopes used for diagnosis and/or therapy in major clinical areas.

Radiopharmaceutical Drug Composition

• A radiopharmaceutical consists of a drug component and a radioactive component.
• The drug component localizes the radioactive component in specific organs or tissues.
• The radioactive component emits gamma rays for diagnostic imaging or particulate radiation for radionuclide therapy.

Radiopharmaceutical Uses

• Diagnostic Radiopharmaceuticals: Used for diagnosis and monitoring various disease states, with relatively small radiation doses.
  • Examples: 99mTc diphosphonates (bone imaging), 99mTc macroaggregated albumin (lung imaging), 201TI thallous chloride (myocardial perfusion imaging).
• Therapeutic Radiopharmaceuticals: Used in the treatment of various disease states, with relatively large radiation doses to cause localized damage.
  • Example: 131I sodium iodide (treatment of thyrotoxicosis or thyroid cancer).

Production of Radionuclides

• Charged particle bombardment: Accelerators like cyclotrons bombard target materials with charged particles to produce radionuclides, leading to an unstable state required for the desired outcome.
• Neutron bombardment: Nuclear reactors bombard target materials with neutrons.

Radiopharmaceutical Generators

• A long-lived parent radionuclide decays into a short-lived daughter radionuclide, for example Technetium-99m from Molybdenum-99.
• The daughter radionuclide is chemically separated from the parent for use in various medical procedures.

Types of Radioactivity Emitters

• Alpha emitters: Heavy, positively charged particles with low penetrating power. These are rarely used in radiopharmaceuticals due to their high damage potential at the cellular level. Internal use is avoided.
• Beta emitters (and beta +): Beta particles have moderate penetrating power and are frequently used in therapeutic radiopharmaceuticals. They can target specific tissues and help in treating conditions like thyroid issues or tumor tissues.
• Gamma emitters: These are electromagnetic waves with high penetrating power and no mass. Gamma rays are often used in diagnostic imaging procedures.

Radiopharmaceutical Imaging Techniques

• Positron Emission Tomography (PET): Uses specialized gamma cameras with detectors placed 180 degrees apart to create images in three dimensions.
• 18F-FDG (flurodeoxyglucose): A commonly used PET radiopharmaceutical for tumor detection.

Radiopharmacy Facilities

• Terminal sterilization: It is necessary but not possible for short-half-life radionuclides.
• Clean rooms: Used to maintain sterility and prevent contamination during preparation.
• Laminar flow cabinets or isolators: Essential for sterile preparation of radiopharmaceuticals.
• Shielding: Shielding is important to protect health care workers and patients. Beta emitters use materials like perspex/aluminium, and gamma emitters require thicker lead or tungsten.

Radiopharmacy Procedures

• Preparation of radiopharmaceuticals: Kits and processes ensure quality control and proper production of these specialized medications.

Explore the specialty practice of radio pharmacy, focusing on the use of radiopharmaceuticals. This quiz covers the composition and applications of diagnostic and therapeutic radiopharmaceuticals in clinical settings. Test your knowledge on this important field of pharmacy!