Introduction

Radiopharmaceutical is a drug contain radioactive material and used for medical purpose; diagnosing and to treat certain diseases. In the field of Nuclear Medicine, almost 95% is indicated for diagnosing diseases both cancer and non-cancer type. The dose given is small and drug administration is consider safe provided that patients adhered to the radiation protection principle as advised.

Radiopharmaceutical has two components; radionuclide and pharmaceutical. Radionuclide will emit radioactive ray that possesses different energy depending on the type of radioactive used whereas pharmaceutical serves as a carrier to transport radioactive to the targeted cell such as cancerous cells. Radiopharmaceutical could only be given to the patient by qualified medical staffs under supervision of nuclear medicine specialist and only available in the hospitals that offered this service.

Types of Radiopharmaceuticals

Radiopharmaceuticals can be divided into 2 types depending on the intended use;

1. Radiopharmaceuticals intended use to diagnose disease.
2. Radiopharmaceuticals intended use for treating disease.

Radiopharmaceuticals Intended Use To Diagnose Disease

Radiopharmaceutical for this purpose contain radioactive material that will produce radiation emission, known as gamma rays. Gamma rays can be detected by using radiation detection equipment or devices such as camera scintillation imaging, Single Photon Emission Computed Tomography (SPECT) and Positron Emission Tomography/Computed Tomography (PET/CT). If this radiopharmaceutical is injected into the patient, it will either pass through certain organs in the body or being take up by them. After that, the rays will be detected by gamma ray detector cameras and generate images. The information gathered will be used by the Nuclear Physicians to report the status of the patient assessment.

Examples of images for bone imaging procedure after radiopharmaceutical been administered for diagnostic purpose.

(Source: http://www.who.int/entity/diagnostic_imaging/imaging_modalities/nuclearmed.jpg)

Radiopharmaceuticals Intended Use for Disease Treatment

Radiopharmaceutical for this purpose have radioactive materials that will emit higher energy radiation emission of beta particles or alpha particles. This radiation could kill cancer cells or cancer stem cells. Drugs that injected into the patient’s body will travel and remain in the cancer tissue. Consequently, the cancer tissues will be damaged and died. The results of treatment could not be seen in near future because the damaged cells may take a while to decease. Patients may be quarantined after taking this medicine for radiation safety.

Use/Indication

Listed below are some of the radiopharmaceuticals commonly used and it respective indication;

When radiopharmaceutical is given?

Patient who are referred to Nuclear Medicine Department is eligible to use this medication. Sufficient explanation regarding the procedures to be performed will be given by a nuclear medicine physician. Radiopharmaceutical will only be given after the patient agree to continue with the prescribed procedure.

How to administer

Various form of pharmaceutical dosage available for pharmaceuticals. Usually patient will be administered intravenously or given orally; either in liquid form (to drink) or capsule form (to swallow). There are also drugs in the form of gas to be inhaled by the patient. This radiopharmaceutical should only be given to patients in hospital setting only or to be specified, in Nuclear Medicine Department. Patients are not supplied with this medication to take home.

Dose Grant

Unlike other pharmaceutical preparations, instead of using dose measurement in milligrams as quantity of intake given to patient, radiopharmaceuticals usually use measurement unit as Curie (Ci) (Non-SI unit) or Megabecquerel (MBq) (SI Units). The dose given will be determined by the nuclear medicine physician. There are variation in the dose administered to children and adults. Body weight also to be considered in determining the dose given to patient.

Matters of concern

Before and decided to use radiopharmaceuticals for diagnosis or treatment of disease, here are some things that need to be addressed;

1. Make sure the patient is not allergic to any ingredient content in the drugs used.
2. Make sure the patient is not pregnant.
3. Patient is advised to stop breast-feeding for certain period of time.
4. Consult your doctor if your child or your parents are to be given this medicine.
5. Inform the doctor if the patient is on any medicine, traditional medicine, herbs and supplements (supplements).
6. Inform your doctor if the patient smoke or drink alcohol.

However, make sure you talk to your doctor about the benefits versus the risks posed by exposure to the radiation received from the use of radiopharmaceuticals.

Possible Side Effects

1. Nausea
2. Breathless
3. Bronchospasm (acute narrowing of respiratory airways)
4. Reduction of blood pressure
5. Hives
6. Flushing
7. Chills
8. Cough
9. Bradycardia( slow in heart beat)
10. Cramp
11. Dizziness

If patient has not experience any of the above signs and feels uncomfortable, please inform the doctor or any medical practitioner immediately. Side effects may occur after leaving the hospital.

References

1. AgensiNuklear Malaysia. Warta Nuklear Malaysia. PerubatanNuklear (PDF). Jilid 4. Bilangan 3 Sept-Dis 2011.
2. Gambar – http://www.who.int/diagnostic_imaging/imaging_modalities/dim_plain-radiography/en/index7.html
3. http://apps.who.int/phint/en/p/docf/
4. http://www.drugs.com/drug-class/radiopharmaceuticals.html
5. http://www.whatisnuclearmedicine.com/Home 6. Saha G.P. (2010). Fundamental of Nuclear Pharmacy (6th ed.). New York: Springer Science+Business Media
6. Video – http://www.snmmi.org/ClinicalPractice/content.aspx?ItemNumber=6539
7. Munjal, A., & Gupta, N. (2020). Radiopharmaceuticals. https://europepmc.org/article/nbk/nbk554440