Cytotoxic agents drug interactions

Many drugs interact with folate to affect its absorption, antagonize its biochemical activity, or increase its loss from the body. These drugs include ethanol, phenytoin, and oral contraceptives. Salicylates can compete with foUc acid for plasma protein binding. Methotrexate, a cytotoxic agent, is a folate antagonist that inhibits the biosynthesis of this coenzyme. 

We have examined the effects of llavonoids and isoflavonoids on the P-gp-and MRP- mediated MDR mechanisms in both mouse lymphoma and human breast cancer cell lines. The interactions of the drug transporters P-gp or MRP with flavonoids or isoflavonoids might be worth their use as anticancer agents, such as a single administration or a combination cancer therapy with cytotoxic agents such as mitomycin C (MMC). Differences in the activities of the P-gp and the MRP-mediated efflux pump could be found in the presence of flavonoids and isoflavonoids. 

No formal drug interaction studies have been conducted with pegylated liposomal doxorubicin, liposomal daunorubicin, or Myocet. Caution should be exercised when using drugs known to interact with doxorubicin or daunorubicin. Equally, caution should be exercised when giving any other cytotoxic drugs, especially myelotoxic agents, at the same time. 

Drug-drug interactions Imatinib Peripheral neuropathy is uncommon in imatinib-treated patients and has previously been reported only during combination therapy with cytotoxic agents that affect microtubule function, such as vinca alkaloids and taxanes. A suspected adverse interaction with amlodipine has been reported, with a temporal association between amlodipine and symptoms of imatinib toxicity [21 ]. 

Hepatic or renal insufficiency does not significantly alter the pharmacokinetics of CP (194). Since immunosuppressive activity resides exclusively in the metabolites of CP (i.e., phosphoromide mustard and acrolein), pharmacokinetics are not predicted by the parent compound. Correlations between CP pharmacokinetics and pharmacodynamics are difficult to demonstrate. Measuring the metabolites is technically difficult (211). Drug interaction with other cytotoxic agents may increase neutropenia. One case report found the combination of CP plus infliximab was more likely to cause T-cell lymphopenia than either agent alone (212). 

Despite the evidence for the cytotoxicity of CNTs, there are an increasing number of published studies that support the potential development of CNT-based biomaterials for tissue regeneration (e.g., neuronal substrates [143] and orthopedic materials [154—156]), cancer treatment [157], and drug/vaccine delivery systems [158, 159]. Most of these applications will involve the implantation and/or administration of such materials into patients as for any therapeutic or diagnostic agent used, the toxic potential of the CNTs must be evaluated in relation to their potential benefits [160]. For this reason, detailed investigations of the interactions between CNTs/CNT-based implants and various cell types have been carried out [154, 155, 161]. A comprehensive description of such results, however, is beyond the scope of this chapter. Extensive reviews on the biocompatibility of implantable CNT composite materials [21, 143, 162] and of CNT drug-delivery systems [162] are available. 

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