Iodipamide is a radiographic contrast agent that blocks X-rays and appears opaque on X-ray film, thereby enhancing the visibility of the bile ducts and gallbladder. The mechanism of action of iodipamide involves its ability to absorb X-rays due to the high atomic number of iodine. This property allows it to create a contrast between tissues that contain iodine and those that do not. When administered in vivo, iodipamide is removed from the liver and secreted into the biliary tract. The compound interacts with various enzymes, proteins, and other biomolecules. It is also an inhibitor of cholesteryl ester transfer protein. Iodipamide stimulates canalicular bile flow, with a choleretic potency of 22 mL/mmol, approximately 3 times that of taurocholate (7.8 mL/mmol). The plasma erythritol clearance increases linearly with the excretion of iodipamide, indicating that iodipamide stimulates canalicular bile flow. The compound's biliary transport maximum (Tm) has been well-characterized in animal models. Iodipamide binds strongly to serum albumin, which delays its transport from plasma to bile.

In vitro, iodipamide interacts with various enzymes, proteins, and other biomolecules. It is also an inhibitor of cholesteryl ester transfer protein. The compound's ability to bind to serum albumin has been studied in vitro using equilibrium dialysis or surface plasmon resonance techniques. These studies have shown that iodipamide binds strongly to albumin, which may affect its distribution and elimination. The compound's osmotic activity has been characterized, and its choleretic potency has been compared to that of taurocholate. In vitro studies have also examined the compound's cytotoxicity and immunological interactions. However, detailed in vitro activity data for iodipamide are limited, as its primary function is as an imaging agent rather than a pharmacologically active compound.

In vivo, iodipamide is removed from the liver and secreted into the biliary tract. It stimulates canalicular bile flow with a choleretic potency of 22 mL/mmol, approximately 3 times that of taurocholate (7.8 mL/mmol). The plasma erythritol clearance increases linearly with the excretion of iodipamide, indicating that iodipamide stimulates canalicular bile flow. In canine models, the compound has a biliary transport maximum (Tm) of approximately 1.0 μmole/kg/min. When administered intravenously, iodipamide is rapidly cleared from the blood and excreted into the bile, with only about 10% of the administered dose excreted by the kidneys. The compound binds strongly to serum albumin, which delays its transport from plasma to bile; the half-life of iodipamide transported to bile is approximately 130 minutes. In the absence of albumin, the initial clearance of iodipamide is rapid, with a half-life of approximately 40 minutes transported to bile. These in vivo pharmacokinetic properties are critical for its use as a biliary contrast agent.

In vitro enzyme/receptor binding studies for iodipamide are not standard, as its primary function is as an imaging agent rather than a pharmacologically active compound. However, the compound's interaction with serum albumin has been studied using in vitro binding assays. In these assays, iodipamide is incubated with human or rabbit serum albumin, and the extent of binding is measured using equilibrium dialysis, ultrafiltration, or surface plasmon resonance. The compound's affinity for albumin and its effect on albumin conformation can be assessed. Iodipamide's inhibition of cholesteryl ester transfer protein has also been studied in vitro using enzyme activity assays. These studies provide insights into the compound's distribution and elimination, which are relevant for its use as a contrast agent.

In vitro cell-based assays for iodipamide are not typically performed, as its utility is in diagnostic imaging rather than cellular pharmacology. However, the compound's cytotoxicity has been studied in various cell lines to assess its safety profile. These assays involve culturing cells in the presence of iodipamide at various concentrations and measuring cell viability using MTT or LDH release assays. The compound's effects on cell proliferation, apoptosis, and immune function have also been investigated. These studies are important for evaluating the potential toxic effects of iodipamide, particularly in patients with impaired renal or hepatic function. However, detailed cell-based assay protocols are not well-documented in the literature.

In vivo, iodipamide is administered intravenously for biliary imaging. In animal models, the compound's pharmacokinetics and biliary excretion have been characterized. In canine models, the biliary transport maximum (Tm) of iodipamide is approximately 1.0 μmole/kg/min. In isolated perfused rabbit liver studies, the excretion of iodipamide has been characterized. When the perfusion fluid contained rabbit plasma protein or albumin, the excretion of iodipamide was initially very slow, gradually increasing to approximately 6 μg/g liver/min at 60 minutes. The half-life of iodipamide transported to bile was approximately 130 minutes. When the perfusion fluid did not contain albumin, the initial clearance was rapid, with a half-life of approximately 40 minutes. These studies demonstrate that albumin binding delays the transport of iodipamide from plasma to bile.

Absorption, Distribution and Excretion
To characterize the saturation kinetics of iopamidol, we collected timed blood, urine, and bile samples from two conscious dogs. These dogs were infused with iopamidol at increasing rates to achieve different steady-state plasma concentrations. The bile excretion rate of iopamidol reached an asymptote with increasing plasma concentrations, indicating a bile transport maxima (Tm) of 15.2 to 16.2 mgI/min. Urinary excretion was not a purely first-order kinetic process, and the urinary excretion rate was higher than the glomerular filtration rate after adjusting for plasma protein binding, suggesting that active tubular secretion may play a role. Extrarenal elimination conformed to Michaelis kinetics. Estimates of the maximal excretion rate (Vm) and Michaelis constant (Km) were obtained graphically. The estimated Vm was 4 to 6 times the bile Tm. In acute infusion experiments, only a small fraction of the administered dose of iopamidone was excreted in bile and urine, and only a small fraction remained in the analyzed organs; no significant accumulation of iopamidone in the liver was observed. Iopamidone, a contrast agent used for biliary tract imaging, binds strongly to serum albumin. The relationship between the contrast agent's affinity for albumin and its preferential uptake and excretion in the liver remains unclear. Therefore, this study investigated the effect of serum albumin on the hepatic uptake and excretion of iopamidone in isolated perfused rabbit liver. When the perfusion fluid contained only fully reconstituted rabbit plasma protein or 3.5 g/100 mL rabbit albumin, the excretion of iopamidone was initially very slow. Subsequently, the excretion gradually increased, reaching approximately 6 μg/g liver/min at 60 minutes, and then remained stable. The half-life of iopamidone transported to bile was approximately 130 minutes. When the perfusion fluid did not contain albumin, the initial clearance of iopamidone was rapid, with a half-life of approximately 40 minutes transported to bile. Rabbit serum globulin has no effect on the excretion of iopamidrone. Therefore, the binding of iopamidrone to albumin delays its transport from plasma to bile, possibly due to competition between albumin and hepatic anion-binding proteins. Contrast agents are primarily excreted in feces, bypassing enterohepatic circulation; only about 10% of intravenously administered doses are excreted by the kidneys. Metabolism/Metabolites: Liver.
Iodipamide is primarily excreted through the hepatobiliary system, with minimal renal excretion (approximately 10% of the intravenously administered dose). The compound binds strongly to serum albumin, which delays its transport from plasma to bile. The half-life of iodipamide transported to bile is approximately 130 minutes. In the absence of albumin, the half-life is approximately 40 minutes. Iodipamide is metabolized in the liver. The compound's biliary transport maximum (Tm) has been characterized in animal models. Its pharmacokinetic properties, including its high protein binding and predominantly biliary excretion, are critical for its use as a biliary contrast agent. The compound's low renal excretion makes it suitable for patients with renal impairment, although its use has largely been superseded by newer agents.

Effects During Pregnancy and Lactation
◉ Overview of Use During Lactation
Very little iodine contrast agents administered intravenously are excreted into breast milk, and oral absorption is also poor. Therefore, they are unlikely to enter the infant's bloodstream and will not cause any adverse effects on breastfed infants. Guidelines from multiple professional organizations indicate that breastfeeding mothers do not need to interrupt breastfeeding after receiving iodine-containing contrast agents. However, since there is currently no published experience regarding the use of iopamidol during lactation, other contrast agents may be preferred, especially when breastfeeding newborns or premature infants. ◉ Effects on Breastfed Infants
No published information found as of the revision date. ◉ Effects on Breastfeeding and Breast Milk
No published information found as of the revision date.
Iodipamide has a well-established safety profile, but its use is associated with potential adverse effects. Like other iodinated contrast agents, iodipamide can cause allergic reactions, including rash, urticaria, and anaphylaxis. Nephrotoxicity is a concern with iodinated contrast agents, although iodipamide's low renal excretion may reduce this risk. The compound can also cause hepatotoxicity, particularly in patients with pre-existing liver disease. In animal studies, iodipamide has been shown to have low acute toxicity, with no significant genotoxicity or carcinogenicity. During pregnancy, very little iodinated contrast agent is excreted into breast milk, and oral absorption is poor, so they are unlikely to enter the infant's bloodstream. Guidelines from multiple professional organizations indicate that breastfeeding mothers do not need to interrupt breastfeeding after receiving iodine-containing contrast agents. However, iodipamide's use has largely been superseded by newer contrast agents with improved safety profiles.

[1]. NCIt.

Adipiodone is an organic iodine compound with the chemical formula 3-amino-2,4,6-triiodobenzoic acid, in which one amino hydrogen atom is replaced by a 6-(3-carboxy-2,4,6-triiodoaniline)-6-oxohexanoyl group. It is a water-soluble radioactive contrast agent used for cholecystography and intravenous cholangiography. It is a radiopaque contrast agent. It is an organic iodine compound belonging to the benzoic acid class and also a secondary amide class. It is the conjugate acid of Adipiodone (2-). Iopamidrone is a water-soluble radioactive contrast agent used for cholecystography and intravenous cholangiography. Iopamidrone is a radioactive contrast agent. The mechanism of action of iopamidrone is as an X-ray contrast agent. Iopamidrone meglumine is the meglumine salt form of iopamidrone, a triiodobenzoic acid ester derivative, and also an ionic dimer contrast agent used for diagnostic imaging. After administration in vivo, iopamidrone is cleared from the liver and secreted into the bile ducts. Like other organic iodine compounds, this drug blocks X-rays, appearing opaque on X-ray films; therefore, it enhances the visualization of the bile ducts and gallbladder during cholangiography and cholecystography.
A water-soluble radiocontrast agent used for cholecystography and intravenous cholangiography.
See also: Iopamidol meglumine (note moved to).

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Drug Indications
Iopamidol is used as a contrast agent for cholecystography and intravenous cholangiography.

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Mechanism of Action
Organic iodine compounds block X-rays as they pass through the human body, thus creating a clear contrast between iodine-containing and non-iodine-containing structures. The degree of visualization produced by these iodinated organic compounds is proportional to the total amount (concentration and volume) of the iodinated contrast agent in the X-ray path. Iopamilide is primarily excreted via the hepatobiliary system and concentrated in bile, thus allowing visualization of the gallbladder and bile ducts. ...Iodine in the contrast agent is responsible for absorbing X-rays, thereby visualizing the examined organ system or other areas. ...

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Therapeutic Use
Contrast Agents
Iopamilide meglumine is indicated for the following intravenous cholangiography and cholecystography: (a) for the differential diagnosis of acute abdominal diseases, to visualize the gallbladder and bile ducts; (b) for cholangiography, especially in patients with symptoms after cholecystectomy; (c) for patients who cannot take contrast agents orally or absorb them from the gastrointestinal tract, to visualize the gallbladder. /US Product Label Contains/
Therapeutic Category: Diagnostic Aids (Radiosensitive Media - Cholecystography)
Therapeutic Category (Veterinary): Diagnostic Aids (Radiosensitive Media)

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Drug Warnings
Iopamilide meglumine is contraindicated for intrathecal injection.
Iopamilide meglumine is contraindicated in patients with hypersensitivity to iopamilide salts or who have experienced a hypersensitivity reaction to the test dose. Contraindicated in patients with severe renal and hepatic impairment. Serious adverse reactions have been reported due to accidental intrathecal administration of iodinated contrast agents unsuitable for intrathecal injection. These serious adverse reactions include: death, seizures, cerebral hemorrhage, coma, paralysis, arachnoiditis, acute renal failure, cardiac arrest, seizures, rhabdomyolysis, hyperthermia, and cerebral edema. Special care must be taken to ensure that this product is not accidentally administered intrathecally. There is a possibility of accidental entry into the intrathecal space during epidural administration. Therefore, epidural procedures, such as pain management catheter placement, should not be performed while using this product. For more complete data on drug warnings for iopamidol (15 in total), please visit the HSDB record page. Pharmacodynamics: Following intravenous injection of cholelithoxine meglumine, iopamidol is transported to the liver and rapidly secreted. It becomes visible in bile within 10 to 15 minutes after injection, and the hepatic ducts and common bile duct can be observed even in patients who have undergone cholecystectomy. Except for patients with impaired liver function, the bile ducts become clearly visible approximately 25 minutes after injection. The gallbladder begins to fill within 1 hour after injection and reaches maximum filling volume after 2 to 2.5 hours. Except for approximately 10% of the intravenously injected dose, which is excreted through the kidneys, the remaining contrast agent does not undergo enterohepatic circulation and is ultimately excreted in the feces.
Iodipamide is a water-soluble radiographic contrast media for intravenous cholangiography and cholecystography. It is a tri-iodinated benzoate derivative and ionic dimeric contrast agent. The compound's mechanism of action involves its ability to absorb X-rays due to the high atomic number of iodine, creating a contrast between tissues that contain iodine and those that do not. Iodipamide is removed from the liver and secreted into the biliary tract, enhancing the visibility of the bile ducts and gallbladder. The compound has a well-characterized biliary transport maximum (Tm) of approximately 1.0 μmole/kg/min in canine models. Iodipamide stimulates canalicular bile flow with a choleretic potency of 22 mL/mmol, approximately 3 times that of taurocholate. It binds strongly to serum albumin, which delays its transport from plasma to bile. Iodipamide has been used clinically as a contrast agent for biliary tract imaging, but its use has largely been superseded by newer contrast agents with improved safety profiles. It is not intended for therapeutic use.

C20H14N2O6I6

1139.75896

1139.51

606-17-7

606-17-7;3521-84-4 (meglumine);2618-26-0 (Na+);

3739

White to off-white solid powder

2.8g/cm3

908.6ºC at 760 mmHg

306-308ºC (dec.)

503.3ºC

1.835

6.994

4

6

9

34

714

0

FFINMCNLQNTKLU-UHFFFAOYSA-N

InChI=1S/C20H14I6N2O6/c21-7-5-9(23)17(15(25)13(7)19(31)32)27-11(29)3-1-2-4-12(30)28-18-10(24)6-8(22)14(16(18)26)20(33)34/h5-6H,1-4H2,(H,27,29)(H,28,30)(H,31,32)(H,33,34)

3-[[6-(3-carboxy-2,4,6-triiodoanilino)-6-oxohexanoyl]amino]-2,4,6-triiodobenzoic acid

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

DMSO : ~125 mg/mL (~109.67 mM)

Solubility in Formulation 1: ≥ 2.08 mg/mL (1.82 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: 2.08 mg/mL (1.82 mM) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution; with ultrasonication.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 2.08 mg/mL (1.82 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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 (Please use freshly prepared in vivo formulations for optimal results.)