will increase the level or effect of lonafarnib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.lopinavirMonitor Closely (1)lopinavir will increase the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Minor (1)cyclophosphamide will increase the level or effect of lopinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.lorlatinibMinor (1)cyclophosphamide will increase the level or effect of lorlatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.losartanMinor (1)cyclophosphamide will increase the level or effect of losartan by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.lovastatinMinor (1)cyclophosphamide will increase the level or effect of lovastatin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.lumacaftor/ivacaftorMonitor Closely (1)lumacaftor/ivacaftor, cyclophosphamide. affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor. In vitro studies suggest that lumacaftor may induce and ivacaftor may inhibit CYP2B6 substrates. .Minor (1)cyclophosphamide will increase the level or effect of lumacaftor/ivacaftor by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.lumefantrineMinor (1)cyclophosphamide will increase the level or effect of lumefantrine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.lurasidoneMinor (1)cyclophosphamide will increase the level or effect of lurasidone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.macimorelinMinor (1)cyclophosphamide will increase the level or effect of macimorelin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.maravirocMinor (1)cyclophosphamide will increase the level or effect of maraviroc by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.marijuanaMinor (1)cyclophosphamide will increase the level or effect of marijuana by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.mechlorethamineMonitor Closely (2)mechlorethamine, cyclophosphamide. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration with mechlorethamine may increase the risk of immunosuppression and myelosuppression. cyclophosphamide, mechlorethamine. Either increases toxicity of the other by pharmacodynamic synergism. Use Caution/Monitor. Coadministration with mechlorethamine may increase the risk of immunosuppression and myelosuppression.medroxyprogesteroneMinor (1)cyclophosphamide will increase the level or effect of medroxyprogesterone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.mefloquineMinor (1)cyclophosphamide will increase the level or effect of mefloquine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.meningococcal group B vaccineMonitor Closely (1)cyclophosphamide decreases effects of meningococcal group B vaccine by pharmacodynamic antagonism. Use Caution/Monitor. Individuals with altered immunocompetence may have reduced immune responses to the vaccine.mestranolMinor (1)cyclophosphamide will increase the level or effect of mestranol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.metaxaloneMinor (1)cyclophosphamide will increase the level or effect of metaxalone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.methadoneMinor (1)cyclophosphamide will increase the level or effect of methadone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.methylergonovineMinor (1)cyclophosphamide will increase the level or effect of methylergonovine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.methylprednisoloneMinor (1)cyclophosphamide will increase the level or effect of methylprednisolone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.miconazole oralMinor (1)cyclophosphamide will increase the level or effect of miconazole oral by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.midazolamMinor (1)cyclophosphamide will increase the level or effect of midazolam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.midazolam intranasalMinor (1)cyclophosphamide will increase the level or effect of midazolam intranasal by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.midostaurinMinor (1)cyclophosphamide will increase the level or effect of midostaurin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.mifepristoneMonitor Closely (2)mifepristone will increase the level or effect of cyclophosphamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor. mifepristone will increase the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Minor (1)cyclophosphamide will increase the level or effect of mifepristone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.mirtazapineMinor (1)cyclophosphamide will increase the level or effect of mirtazapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.mitotaneMonitor Closely (1)mitotane decreases levels of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. Mitotane is a strong inducer of cytochrome P-4503A4; monitor when coadministered with CYP3A4 substrates for possible dosage adjustments.modafinilMinor (1)cyclophosphamide will increase the level or effect of modafinil by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.montelukastMinor (1)cyclophosphamide will increase the level or effect of montelukast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.naldemedineMinor (1)cyclophosphamide will increase the level or effect of naldemedine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.naloxegolMinor (1)cyclophosphamide will increase the level or effect of naloxegol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nefazodoneMinor (1)cyclophosphamide will increase the level or effect of nefazodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nelfinavirMonitor Closely (1)nelfinavir will increase the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.Minor (1)cyclophosphamide will increase the level or effect of nelfinavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.netupitant/palonosetronMinor (1)cyclophosphamide will increase the level or effect of netupitant/palonosetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nevirapineMinor (1)cyclophosphamide will increase the level or effect of nevirapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nicardipineMinor (1)cyclophosphamide will increase the level or effect of nicardipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nifedipineMinor (1)cyclophosphamide will increase the level or effect of nifedipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nilotinibMinor (1)cyclophosphamide will increase the level or effect of nilotinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nimodipineMinor (1)cyclophosphamide will increase the level or effect of nimodipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.nisoldipineMinor (1)cyclophosphamide will increase the level or effect of nisoldipine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.norethindroneMinor (1)cyclophosphamide will increase the level or effect of norethindrone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ocrelizumabMonitor Closely (1)cyclophosphamide and ocrelizumab both increase immunosuppressive effects; risk of infection. Use Caution/Monitor. Coadministration of ocrelizumab with immunosuppressants may increase the risk of immunosuppression.ofatumumab SCMonitor Closely (1)ofatumumab SC, cyclophosphamide. Either increases effects of the other by immunosuppressive effects; risk of infection. Use Caution/Monitor. Consider the risk of additive immune system effects when coadministering immunosuppressive therapies with coadministration. When switching from therapies with immune effects, take into account the duration and mechanism of action of these therapies when initiating ofatumumab SC.olaparibMonitor Closely (1)cyclophosphamide and olaparib both increase pharmacodynamic synergism. Use Caution/Monitor. Coadministration with other other myelosuppressive anticancer agents, including DNA damaging agents, may potentiate and prolongate the myelosuppressive toxicity. Minor (1)cyclophosphamide will increase the level or effect of olaparib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ombitasvir/paritaprevir/ritonavirMinor (1)cyclophosphamide will increase the level or effect of ombitasvir/paritaprevir/ritonavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC)Minor (1)cyclophosphamide will increase the level or effect of ombitasvir/paritaprevir/ritonavir & dasabuvir (DSC) by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.omeprazoleMinor (1)cyclophosphamide will increase the level or effect of omeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ondansetronMinor (1)cyclophosphamide will increase the level or effect of ondansetron by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.osilodrostatMinor (1)cyclophosphamide will increase the level or effect of osilodrostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.osimertinibMinor (1)cyclophosphamide will increase the level or effect of osimertinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ospemifeneMinor (1)cyclophosphamide will increase the level or effect of ospemifene by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.oxycodoneMinor (1)cyclophosphamide will increase the level or effect of oxycodone by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.paclitaxelMinor (1)cyclophosphamide will increase the level or effect of paclitaxel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.paclitaxel protein boundMinor (1)cyclophosphamide will increase the level or effect of paclitaxel protein bound by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.palbociclibMinor (1)cyclophosphamide will increase the level or effect of palbociclib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.paliferminSerious - Use Alternative (1)palifermin increases toxicity of cyclophosphamide by Other (see comment). Avoid or Use Alternate Drug. Comment: Palifermin should not be administered within 24 hrbefore, during infusion of, or within 24 hr after administration of antineoplastic agents. Coadministration of palifermin within 24 hr of chemotherapy resulted in increased severity and duration of oral mucositis.panobinostatMinor (1)cyclophosphamide will increase the level or effect of panobinostat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.paricalcitolMinor (1)cyclophosphamide will increase the level or effect of paricalcitol by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.pazopanibMinor (1)cyclophosphamide will increase the level or effect of pazopanib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.pentobarbitalMonitor Closely (1)pentobarbital will decrease the level or effect of cyclophosphamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor.perampanelMinor (1)cyclophosphamide will increase the level or effect of perampanel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.pexidartinibMinor (1)cyclophosphamide will increase the level or effect of pexidartinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.phenobarbitalMonitor Closely (1)phenobarbital will decrease the level or effect of cyclophosphamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor.pimavanserinMinor (1)cyclophosphamide will increase the level or effect of pimavanserin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.pimozideMinor (1)cyclophosphamide will increase the level or effect of pimozide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.pitolisantMinor (1)cyclophosphamide will increase the level or effect of pitolisant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.polatuzumab vedotinMinor (1)cyclophosphamide will increase the level or effect of polatuzumab vedotin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.pomalidomideMinor (1)cyclophosphamide will increase the level or effect of pomalidomide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ponatinibMinor (1)cyclophosphamide will increase the level or effect of ponatinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.praziquantelMinor (1)cyclophosphamide will increase the level or effect of praziquantel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.primaquineMinor (1)cyclophosphamide will increase the level or effect of primaquine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.primidoneMonitor Closely (1)primidone will decrease the level or effect of cyclophosphamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor.progesterone intravaginal gelMinor (1)cyclophosphamide will increase the level or effect of progesterone intravaginal gel by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.progesterone micronizedMinor (1)cyclophosphamide will increase the level or effect of progesterone micronized by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.progesterone, naturalMinor (1)cyclophosphamide will increase the level or effect of progesterone, natural by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.quazepamMinor (1)cyclophosphamide will increase the level or effect of quazepam by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.quetiapineMinor (1)cyclophosphamide will increase the level or effect of quetiapine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.quinidineMinor (1)cyclophosphamide will increase the level or effect of quinidine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.quinineMinor (1)cyclophosphamide will increase the level or effect of quinine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rabeprazoleMinor (1)cyclophosphamide will increase the level or effect of rabeprazole by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ranolazineMinor (1)cyclophosphamide will increase the level or effect of ranolazine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.regorafenibMinor (1)cyclophosphamide will increase the level or effect of regorafenib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.repaglinideMinor (1)cyclophosphamide will increase the level or effect of repaglinide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ribociclibMinor (2)ribociclib will increase the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown. cyclophosphamide will increase the level or effect of ribociclib by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rifabutinMinor (1)cyclophosphamide will increase the level or effect of rifabutin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rifampinMonitor Closely (2)rifampin will decrease the level or effect of cyclophosphamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor. rifampin will decrease the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor.rimegepantMinor (1)cyclophosphamide will increase the level or effect of rimegepant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.riociguatMinor (1)cyclophosphamide will increase the level or effect of riociguat by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ritonavirMonitor Closely (2)ritonavir will increase the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Use Caution/Monitor. ritonavir will increase the level or effect of cyclophosphamide by affecting hepatic enzyme CYP2B6 metabolism. Use Caution/Monitor.Minor (1)cyclophosphamide will increase the level or effect of ritonavir by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rivaroxabanMinor (1)cyclophosphamide will increase the level or effect of rivaroxaban by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.roflumilastMinor (1)cyclophosphamide will increase the level or effect of roflumilast by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rolapitantMinor (1)cyclophosphamide will increase the level or effect of rolapitant by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.romidepsinMinor (1)cyclophosphamide will increase the level or effect of romidepsin by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.ropeginterferon alfa 2bSerious - Use Alternative (1)ropeginterferon alfa 2b, cyclophosphamide. Either increases toxicity of the other by Other (see comment). Avoid or Use Alternate Drug. Comment: Myelosuppressive agents can produce additive myelosuppression. Avoid use and monitor patients receiving the combination for effects of excessive myelosuppression.ropivacaineMinor (1)cyclophosphamide will increase the level or effect of ropivacaine by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Minor/Significance Unknown.rucaparibMonitor Closely (1)rucaparib will increase the level or effect of cyclophosphamide by affecting hepatic/intestinal enzyme CYP3A4 metabolism. Modify Therapy/Monitor Closely. Adjust dosage of CYP3A4 substrates, if clinically indicated.ruxolitinibMinor (1)cyclophosphamide will increase the level or effect of ruxolitinib by affecting hepatic/intestinal enzyme CYP3A4 metabolism.