MBqkg

MBq/kg, or megabecquerel per kilogram, is a radiopharmaceutical dosing metric used in nuclear medicine and radiopharmacology. It expresses the administered radioactive activity relative to a patient’s body mass, enabling dose personalization to balance therapeutic effectiveness with safety. MBq denotes one million decays per second, while kg represents body weight, so MBq/kg describes decays per second per kilogram of tissue.

Calculation and use are straightforward: total administered activity (in MBq) equals the MBq/kg dose level multiplied by the patient’s body weight in kilograms. For example, a patient weighing 70 kg dosed at 3 MBq/kg would receive 210 MBq of activity. This approach helps tailor treatment to individual patients, particularly when radiopharmaceuticals have narrow therapeutic windows or varying pharmacokinetics.

Applications are common in nuclear medicine therapies that use radioactive isotopes, including examples such as certain lectures and targeted radiotherapies. The MBq/kg metric is often chosen to standardize dosing across patients with different body sizes and to support safety monitoring, especially in pediatric populations where precise dosing is critical.

Clinical considerations include the choice of radionuclide, disease target, and patient factors such as organ function and prior treatments. Appropriate MBq/kg ranges depend on the specific radiopharmaceutical and indication, and guidelines from regulatory bodies and professional societies may provide recommended values. Because actual dose delivered to tumors and organs depends on pharmacokinetics and distribution, dosimetry and imaging can be used to refine dosing and assess potential toxicity.