The Effect of Dexamethasone on the Neurotoxicity of Nitroimidazole Compounds
A total of 300 patients have been entered in our Institution to receive either Misonidazole or Metronidazole in order to study the usefulness of these compounds as hypoxic cell sensitizers. The present report deals with our attempts to reduce the toxicity of these drugs.
Acute GI toxicity, although present in 30–40% of our patients tpending on the total dose and type of drug), has not been our dose limiting factor. On the other hand, peripheral neuropathies have been the major obstacle in reaching blood and tumour tissue drug therapeutic levels.
Consequently we have explored the possible protective effect of Dexamethasone against the neurotoxicity of Misonidazole. A preliminary analysis of our presently ongoing prospective study is suggestive that Dexamethasone may exert a protective effect, although we have found that unlike Phenytoin it does not appear to alter the kinetics of Misonidazole in blood.
KeywordsPeripheral Neuropathy Maximum Tolerable Dose Sensory Peripheral Neuropathy High Performance Liquid Chromatography Assay Ongoing Prospective Study
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