FLUORIDE ION F-18 (as sodium fluoride F-18) is a radioactive diagnostic agent for positron emission tomography (PET) indicated for imaging of bone to define areas of altered osteogenic activity. FLUORIDE ION F-18 normally accumulates in the skeleton in an even fashion, with greater deposition in the axial skeleton (e.g. vertebrae and pelvis) than in the appendicular skeleton and greater deposition in the bones around joints than in the shafts of long bones. Increased FLUORIDE ION F-18 deposition in the bone can occur in areas of increased osteogenic activity during growth, infection, malignancy (primary or metastatic) following trauma, or inflammation of the bone.

Iodide I-131 (as Sodium iodide I-131) is a radioisotopic drug used for the treatment and palliation of thyroid malignancy. Therapeutic solutions of Sodium Iodide-131 are indicated for the treatment of hyperthyroidism and thyroid carcinomas that take up iodine. Palliative effects may be observed in patients with advanced thyroid malignancy if the metastatic lesions take up iodine. It is also indicated for use in performance of the radioactive iodide (RAI) uptake test to evaluate thyroid function. Taken orally, sodium iodide I-131 is rapidly absorbed and distributed within the extracellular fluid of the body. The iodide is concentrated in the thyroid via the sodium/iodide symporter, and subsequently oxidized to iodine. The destruction of thyroidal tissue is achieved by the beta emission of sodium iodide I-131.

I-123 radiolabeled ortho-iodohippurate is commonly employed for evaluating effective renal plasma flow (ERPF) by means of either in vivo scintigraphy and/or plasma clearance curves. It has been used to evaluate renal functioning in patients with obstructive uropathy, vesicorenal reflux, hypertensiion due to renal artery stenosis.

IODOHIPPURIC ACID I-131 (ortho-Iodohippuric Acid I-131, [I-123]-OIH) is an iodine-containing compound used in pyelography as a radiopaque medium. Iodine-123 labelled ortho-Iodohippuric acid was used in the early 1970's as a kidney imaging agent or tracer that "lights-up" inside your body when scanned, but over the years its use has declined. [I-123]-OIH is primarily extracted by the renal tubules and has excellent pharmacokinetic properties, with a clearance only slightly less than that of p-aminohippuran, but its use has been compromised by the suboptimal imaging characteristics of the 364-keV photon of 131I and the delivery of relatively high radiation doses to kidneys and thyroid in patients with impaired renal function

Fe-59 is an isotope of iron. It has a half-life of 44.5 days and decays by emitting a beta particle. In medicine, ferrous citrate Fe 59 is indicated, by intravenous administration, to determine various parameters of the kinetics of iron metabolism, including plasma iron clearance, plasma iron turnover rate, and the utilization of iron in new red blood cells. An oxidized form of iron cation, ferric cation Fe59, is also used to study the processes of iron metabolism.

Iodine-124 (124I), a positron emission tomography (PET) radiotracer, can be used in a variety of PET applications, such as protein and antibody iodinations, as well as in the design and synthesis of new PET tracers. I-124 has the potential to improve the current clinical practice in the diagnosis and treatment of differentiated thyroid cancer (DTC). In addition, 124 PET/CT is a sensitive tool to detect some new lesions that are not visualized on the post-treatment I-131 scan. Recently published article has described that in order to I-124 used as a mainstream, this substance should be more commercially available and at a more chipper.

Iodide ion I-125 is radioisotope of iodine with half-life 59.4 days. It decays with the emission of low-energy gamma rays. It is used as a source for bone densitometry devices, protein iodination. Seeds implantations with I-125 are used in the clinics for the treatment of prostate cancer, malignant biliary obstruction, non-small cell lung cancer, colorectal cancer, uveal melanoma, and other tumors.