Radiopharmaceuticals, or medicinal radiocompounds, are a group of

pharmaceutical drug A medication (also called medicament, medicine, pharmaceutical drug, medicinal drug or simply drug) is a drug used to diagnose, cure, treat, or prevent disease. Drug therapy (pharmacotherapy) is an important part of the medical field an ...

s containing

radioactive isotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferr ...

s. Radiopharmaceuticals can be used as diagnostic and

therapeutic A therapy or medical treatment (often abbreviated tx, Tx, or Tx) is the attempted remediation of a health problem, usually following a medical diagnosis. As a rule, each therapy has indications and contraindications. There are many different ...

agents. Radiopharmaceuticals emit radiation themselves, which is different from

contrast media A contrast agent (or contrast medium) is a substance used to increase the contrast of structures or fluids within the body in medical imaging. Contrast agents absorb or alter external electromagnetism or ultrasound, which is different from radiop ...

which absorb or alter external electromagnetism or ultrasound. Radiopharmacology is the branch of pharmacology that specializes in these agents. The main group of these compounds are the

radiotracer A radioactive tracer, radiotracer, or radioactive label is a chemical compound in which one or more atoms have been replaced by a radionuclide so by virtue of its radioactive decay it can be used to explore the mechanism of chemical reactions by tr ...

s used to diagnose dysfunction in body tissues. While not all medical isotopes are radioactive, radiopharmaceuticals are the oldest and still most common such drugs.

Drug nomenclature

As with other pharmaceutical drugs, there is standardization of the

drug nomenclature Drug nomenclature is the systematic naming of drugs, especially pharmaceutical drugs. In the majority of circumstances, drugs have 3 types of names: chemical names, the most important of which is the IUPAC name; generic or nonproprietary names, ...

for radiopharmaceuticals, although various standards coexist. The International Nonproprietary Names (INNs),

United States Pharmacopeia The ''United States Pharmacopeia'' (''USP'') is a pharmacopeia (compendium of drug information) for the United States published annually by the United States Pharmacopeial Convention (usually also called the USP), a nonprofit organization that ...

(USP) names, and

IUPAC The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is ...

names for these agents are usually similar other than trivial style differences. The details are explained at '' Radiopharmacology § Drug nomenclature for radiopharmaceuticals''.

Specific radiopharmaceuticals

A list of nuclear medicine radiopharmaceuticals follows. Some radioisotopes are used in

ion An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conve ...

ic or inert form without attachment to a pharmaceutical; these are also included. There is a section for each

radioisotope A radionuclide (radioactive nuclide, radioisotope or radioactive isotope) is a nuclide that has excess nuclear energy, making it unstable. This excess energy can be used in one of three ways: emitted from the nucleus as gamma radiation; transferr ...

with a table of radiopharmaceuticals using that radioisotope. The sections are ordered alphabetically by the English name of the radioisotope. Sections for the same element are then ordered by

atomic mass number The mass number (symbol ''A'', from the German word ''Atomgewicht'' tomic weight, also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. It is approxim ...

Calcium-47

⁴⁷ Ca is a beta and gamma emitter.

Carbon-11

¹¹ C is a positron emitter.

Carbon-14

¹⁴C is a beta emitter.

Chromium-51

⁵¹Cr is a gamma emitter.

Cobalt-57

⁵⁷Co is a gamma emitter.

Cobalt-58

⁵⁸Co is a gamma emitter.

Erbium-169

¹⁶⁹Er is a beta emitter.

Fluorine-18

¹⁸F is a positron emitter with a half-life of 109 minutes. It is produced in medical cyclotrons, usually from oxygen-18, and then chemically attached to a pharmaceutical. See

PET scan Positron emission tomography (PET) is a functional imaging technique that uses radioactive substances known as radiotracers to visualize and measure changes in metabolic processes, and in other physiological activities including blood flow, ...

Gallium-67

⁶⁷Ga is a gamma emitter. See gallium scan.

Gallium-68

⁶⁸Ga is a positron emitter, with a 68-minute half-life, produced by

elution In analytical and organic chemistry, elution is the process of extracting one material from another by washing with a solvent; as in washing of loaded ion-exchange resins to remove captured ions. In a liquid chromatography experiment, for exam ...

from germanium-68 in a

gallium-68 generator A germanium-68/gallium-68 generator is a device used to extract the positron-emitting isotope 68Ga of gallium from a source of decaying germanium-68. The parent isotope 68Ge has a half-life of 271 days and can be easily utilized for in-hospital ...

or by proton irradiation of zinc-68. See also positron emission tomography.

Hydrogen-3

³H or

tritium Tritium ( or , ) or hydrogen-3 (symbol T or H) is a rare and radioactive isotope of hydrogen with half-life about 12 years. The nucleus of tritium (t, sometimes called a ''triton'') contains one proton and two neutrons, whereas the nucleus of ...

is a beta emitter.

Indium-111

¹¹¹In is a gamma emitter.

Iodine-123

Iodine-123 Iodine-123 (123I) is a radioactive isotope of iodine used in nuclear medicine imaging, including single-photon emission computed tomography (SPECT) or SPECT/CT exams. The isotope's half-life is 13.2230 hours; the decay by electron capture to tellu ...

(I-123) is a gamma emitter. It is used only diagnostically, as its radiation is penetrating and short-lived.

Iodine-125

¹²⁵I is a gamma emitter with a long half-life of 59.4 days (the longest of all radioiodines used in medicine). Iodine-123 is preferred for imaging, so I-125 is used diagnostically only when the test requires a longer period to prepare the radiopharmaceutical and trace it, such as a fibrinogen scan to diagnose clotting. I-125's gamma radiation is of medium penetration, making it more useful as a therapeutic isotope for brachytherapy implant of radioisotope capsules for local treatment of cancers.

Iodine-131

¹³¹I is a beta and gamma emitter. It is used both to destroy thyroid and thyroid cancer tissues (via beta radiation, which is short-range), and also other neuroendocrine tissues when used in MIBG. It can also be seen by a gamma camera, and can serve as a diagnostic imaging tracer, when treatment is also being attempted at the same time. However iodine-123 is usually preferred when only imaging is desired.

Diagnostic

Therapeutic

Iron-59

⁵⁹Fe is a beta and gamma emitter.

Krypton-81m

⁸¹Kr^m is a gamma emitter.

Lutetium-177

¹⁷⁷Lu is a beta emitter.

Nitrogen-13

¹³N is a positron emitter.

Oxygen-15

¹⁵O is a positron emitter.

Phosphorus-32

³²P is a beta emitter.

Radium-223

²²³Ra is an alpha emitter.

Rubidium-82

⁸²Rb is a positron and gamma emitter.

Samarium-153

¹⁵³Sm is a beta and gamma emitter.

Selenium-75

⁷⁵Se is a gamma emitter.

Sodium-22

²²Na is a positron and gamma emitter.

Sodium-24

²⁴Na is a beta and gamma emitter.

Strontium-89

⁸⁹Sr is a beta emitter.

Technetium-99m

Technetium-99m Technetium-99m (99mTc) is a metastable nuclear isomer of technetium-99 (itself an isotope of technetium), symbolized as 99mTc, that is used in tens of millions of medical diagnostic procedures annually, making it the most commonly used medical ra ...

is a gamma emitter. It is obtained on-site at the imaging center as the soluble pertechnetate which is eluted from a

technetium-99m generator A technetium-99m generator, or colloquially a technetium cow or moly cow, is a device used to extract the metastable isotope 99mTc of technetium from a decaying sample of molybdenum-99. 99Mo has a half-life of 66 hours and can be easily transp ...

, and then either used directly as this soluble salt, or else used to synthesize a number of technetium-99m-based radiopharmaceuticals.

Thallium-201

²⁰¹Tl is a gamma emitter.

Xenon-133

¹³³Xe is a gamma emitter.

Yttrium-90

⁹⁰Y is a beta emitter.

References

External links

Medical radionuclides production simulator – IAEA
{{Therapeutic radiopharmaceuticals Radiopharmaceuticals Medicinal chemistry Positron emission tomography Medical diagnosis Drugs Molecular imaging Medicinal radiochemistry PET radiotracers Chemicals in medicine Isotopes