Iodobenzamide (IBZM or iolopride) is a pharmaceutical drug used for diagnostic purposes. It is a

dopamine antagonist A dopamine antagonist, also known as an anti-dopaminergic and a dopamine receptor antagonist (DRA), is a type of drug which blocks dopamine receptors by receptor antagonism. Most antipsychotics are dopamine antagonists, and have been used in t ...

and it can be used by

nuclear medicine physician Nuclear medicine physicians, also called nuclear radiologists or simply nucleologists, are medical specialists that use tracers, usually radiopharmaceuticals, for diagnosis and therapy. Nuclear medicine procedures are the major clinical applicatio ...

s as a

radioactive tracer A radioactive tracer, radiotracer, or radioactive label is a synthetic derivative of a natural compound in which one or more atoms have been replaced by a radionuclide (a radioactive atom). By virtue of its radioactive decay, it can be used to ...

for

SPECT Single-photon emission computed tomography (SPECT, or less commonly, SPET) is a nuclear medicine tomographic imaging technique using gamma rays. It is very similar to conventional nuclear medicine planar imaging using a gamma camera (that is, ...

where the radioactive

isotope Isotopes are distinct nuclear species (or ''nuclides'') of the same chemical element. They have the same atomic number (number of protons in their Atomic nucleus, nuclei) and position in the periodic table (and hence belong to the same chemica ...

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 13.2232 hours; the decay by electron capture to t ...

iodine-125 Iodine-125 (125I) is a radioisotope of iodine which has uses in biological assays, nuclear medicine imaging and in radiation therapy as brachytherapy to treat a number of conditions, including prostate cancer, uveal melanomas, and brain tumor ...

. The main purpose of a brain study with IBZM is the differentiation of

Parkinson's disease Parkinson's disease (PD), or simply Parkinson's, is a neurodegenerative disease primarily of the central nervous system, affecting both motor system, motor and non-motor systems. Symptoms typically develop gradually and non-motor issues become ...

from other

neurodegenerative A neurodegenerative disease is caused by the progressive loss of neurons, in the process known as neurodegeneration. Neuronal damage may also ultimately result in their death. Neurodegenerative diseases include amyotrophic lateral sclerosis, mul ...

diseases such as

Lewy Body dementia Lewy body dementia (LBD) is an umbrella term for two similar and common subtypes of dementia: dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD). Both are characterized by changes in thinking, movement, behavior, and mood. The ...

and

multiple system atrophy Multiple system atrophy (MSA) is a rare neurodegenerative disorder characterized by tremors, slow movement, muscle rigidity, postural instability (collectively known as parkinsonism), autonomic dysfunction and ataxia. This is caused by progr ...

Study

Iodobenzamide can also be used to treat people that have

schizophrenia Schizophrenia () is a mental disorder characterized variously by hallucinations (typically, Auditory hallucination#Schizophrenia, hearing voices), delusions, thought disorder, disorganized thinking and behavior, and Reduced affect display, f ...

. The Iodobenzamide binds to the Dopamine D2 receptors in the person’s brain and blocks excess neurons that cause an asymmetry in the brain, leaning heavily to the left side. People that receive doses of Iodobenzamide have their brain scanned to monitor their dopamine activity. A study found that patients that were drug-naive (did not have tolerance to the drug) had significant reactions in the left hemisphere of their brain to the drug. Patients with a first dose of Iodobenzamide were scanned and given

benperidol Benperidol, sold under the trade name Anquil among others, is a typical antipsychotic primarily used to treat hypersexuality syndromes and can be used to treat schizophrenia. It is a highly potent butyrophenone derivative and is the most potent ...

(a drug used to treat hypersexuality) then scanned again. Male patients showed a left side heavy brain asymmetry of dopamine receptor binding in a drug-naive state.

Benperidol Benperidol, sold under the trade name Anquil among others, is a typical antipsychotic primarily used to treat hypersexuality syndromes and can be used to treat schizophrenia. It is a highly potent butyrophenone derivative and is the most potent ...

leads to a reversal of the asymmetry. Drug-naive patient’s brains have a harder time binding the

antipsychotic drugs Antipsychotics, previously known as neuroleptics and major tranquilizers, are a class of psychotropic medication primarily used to manage psychosis (including delusions, hallucinations, paranoia or disordered thought), principally in schizoph ...

to the part of their brain that receives the

Dopamine D2 receptor Dopamine receptor D2, also known as D2R, is a protein that, in humans, is encoded by the ''DRD2'' gene. After work from Paul Greengard's lab had suggested that dopamine receptors were the site of action of antipsychotic drugs, several groups, ...

References

Radiopharmaceuticals Salicylamides Iodobenzene derivatives Pyrrolidines Phenol ethers Methoxy compounds {{Nuclear-med-stub