Iohexol development

Jenkins et al. developed a capillary electrophoresis system for the measurement of iohexol as a marker of the glomerular filtration rate (GFR) with a run time of 5.25 min and a coefficient of variation (CV) of 4.3% at 80 mg L" [121]. The GFR, calculated from the plasma clearance, had a reproducibility of 5.47 %. A similar approach (liquid chromatography-mass spectrometry with positive electrospray ionization after enrichment by solid phase extraction) was applied by Putschew et al. for the determination of iodinated contrast agents in treatment plant effluents and surface waters [118]. 

There was no difference in the incidence of adverse effects between iotrolan 320 and iohexol 350 in cardiac angiography for ischemic heart disease in 120 patients (22). There were no serious adverse events. One patient developed mild urticaria after iotrolan. Five patients in each group had mild unspecified delayed reactions. 

The incidence of late adverse reactions to the iso-osmo-lar agent iodixanol has also been investigated in a retrospective comparison with the non-ionic monomer iohexol. Reactions after 3075 injections were reviewed. Patients were sent a written questionnaire to find out about the incidence of any acute or delayed reactions. Those who developed reactions were interviewed by telephone and specific second questionnaires were administered. The incidence of adverse reactions was low (2% for late adverse reactions and 2.3% for acute reactions). There was no significant difference in the incidence of acute or delayed adverse reactions to iohexol and iodixanol and there were no serious reactions (32). 

Hearing disturbances attributable to contrast agents are extremely rare. The hearing loss in this patient developed more than 1 hour after the injection of iohexol, without any evidence of other causes. The authors suggested that the hearing disturbance might have been attributable to cochlear impairment caused by a delayed allergic reaction or chemical toxicity of the contrast medium. 

A 54-year-old woman and a 68-year-old man developed rashes 24 hours after intravascular injection of iohexol (a non-ionic monomer) (205). The woman developed widespread pruritic erythema and eyelid edema. The man developed a maculopapular rash involving the trunk and legs. Both patients were treated with antihistamines, which resulted in complete recovery within 1 week. The man had slight desquamation of the affected area after his rash resolved. Patch tests were positive to iohexol in both patients. The man also had a positive patch test to iodixanol and the woman was positive to the non-ionic monomer ioversol. 

Tolerance of non-ionic contrast media in myelography has been well documented (SEDA-22, 500). A report from India has documented the safety and diagnostic efficacy of the non-ionic monomer iohexol 7-10 ml (iodine 300 mg/ml) injected into the subarachnoid space in 25 patients (302). Only three patients developed minor adverse effects—headache and paresthesia in the legs. 

A 4-year-old boy developed acute generalized exanthematous pustulosis (AGEP) after infusion of ioversol in cardiac catheter studies on three separate occasions [24 ]. Patch testing was positive for ioversol (Optiray) and iohexol (Omnipaque) but not for iotalamate. 

An easy and rapid method with intravenous bolus administration of an iohexol/ PAH mixture in dogs has been developed for simultaneous measurement of GFR and eRPF, based on plasma clearances of both substances (Laroute et al. 1999). 

The formulations of the lipiodol W/O/W emulsion developed by us and the conventional emulsions for TAB (Nakamura et al., 1989) are shown in Table 11.6, together with their physical properties. All the materials used are injectable. The anticancer agent used was Farmorubicin (FARM), which is a powder mixture of eptrubicin hydrochloride (BPI) and lactose. The aqueous contrast medium used was Omnipaque 240 , which is an aqueous solution of 517.7mg/ ml iohexol, 0.1 mg/ml ethylenediaminetetraacetic acid disodium calcium, and 1.21 mg/ml tris(hydroxymethyl)aminomethane. The chemical structures of BPI... 

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