BNF for Children 2011-2012

700 Appendix 1: Interactions BNFC 2011–2012Appendix 1: InteractionsIndinavir (continued). Anti-arrhythmics: indinavir possibly increases plasmaconcentration of .amiodarone—avoid concomitantuse; indinavir possibly increases plasma concentrationof .flecainide (increased risk of ventriculararrhythmias—avoid concomitant use). Antibacterials: indinavir increases plasma concentrationof .rifabutin—avoid concomitant use; metabolismof indinavir accelerated by .rifampicin(reduced plasma concentration—avoid concomitantuse); avoidance of concomitant indinavir in severerenal and hepatic impairment advised by manufacturerof .telithromycinAnticoagulants: avoidance of indinavir advised bymanufacturer of rivaroxaban. Antidepressants: plasma concentration of indinavirreduced by .St John’s wort—avoid concomitant use. Antiepileptics: plasma concentration of indinavirpossibly reduced by .carbamazepine and .phenytoin,also plasma concentration of carbamazepine andphenytoin possibly increased; plasma concentrationof indinavir possibly reduced by .phenobarbital. Antifungals: plasma concentration of indinavirincreased by .itraconazole and .ketoconazole (considerreducing dose of indinavir). Antimalarials: caution with indinavir advised bymanufacturer of artemether/lumefantrine; indinavirpossibly increases plasma concentration of .quinine(increased risk of toxicity)Antimuscarinics: avoidance of indinavir advised bymanufacturer of darifenacin and tolterodine; manufacturerof fesoterodine advises dose reduction whenindinavir given with fesoterodine—consult fesoterodineproduct literature. Antipsychotics: indinavir possibly inhibits metabolismof .aripiprazole (reduce dose of aripiprazole); indinavirpossibly increases plasma concentration of.pimozide (increased risk of ventricular arrhythmias—avoidconcomitant use). Antivirals: avoid concomitant use of indinavir with.atazanavir; plasma concentration of both drugsincreased when indinavir given with darunavir;plasma concentration of indinavir reduced byefavirenz and nevirapine; plasma concentration ofindinavir possibly reduced by .etravirine—avoidconcomitant use; indinavir increases plasma concentrationof .maraviroc (consider reducing dose ofmaraviroc); combination of indinavir with nelfinavirmay increase plasma concentration of either drug (orboth); plasma concentration of indinavir increased byritonavir; indinavir increases plasma concentration ofsaquinavir. Anxiolytics and Hypnotics: increased risk of prolongedsedation when indinavir given with .alprazolam—avoid concomitant use; indinavir possibly increasesplasma concentration of .midazolam (risk of prolongedsedation—avoid concomitant use of oralmidazolam)Atovaquone: plasma concentration of indinavir possiblyreduced by atovaquone. Ciclosporin: indinavir increases plasma concentrationof .ciclosporin. Colchicine: indinavir possibly increases risk of.colchicine toxicity—suspend or reduce dose ofcolchicine (avoid concomitant use in hepatic or renalimpairment)Corticosteroids: plasma concentration of indinavirpossibly reduced by dexamethasone. Cytotoxics: indinavir possibly increases plasma concentrationof .everolimus—manufacturer of everolimusadvises avoid concomitant use; avoidance ofindinavir advised by manufacturer of .pazopanib. Ergot Alkaloids: increased risk of ergotism whenindinavir given with .ergotamine and methysergide—avoidconcomitant use. 5HT 1 Agonists: indinavir increases plasma concentrationof .eletriptan (risk of toxicity)—avoid concomitantuseIndinavir (continued). Lipid-regulating Drugs: possible increased risk ofmyopathy when indinavir given with atorvastatin;possible increased risk of myopathy when indinavirgiven with .rosuvastatin—manufacturer of rosuvastatinadvises avoid concomitant use; increased risk ofmyopathy when indinavir given with .simvastatin(avoid concomitant use). Ranolazine: indinavir possibly increases plasma concentrationof .ranolazine—manufacturer of ranolazineadvises avoid concomitant use. Sildenafil: indinavir increases plasma concentration of.sildenafil—reduce initial dose of sildenafilTadalafil: indinavir possibly increases plasma concentrationof tadalafil. Vardenafil: indinavir increases plasma concentration of.vardenafil—avoid concomitant useIndometacin see NSAIDsIndoramin see Alpha-blockersInfliximab. Abatacept: avoid concomitant use of infliximab with.abatacept. Anakinra: avoid concomitant use of infliximab with.anakinra. Vaccines: avoid concomitant use of infliximab with live.vaccines (see p. 599)Influenza Vaccine see VaccinesInsulin see AntidiabeticsInterferon Alfa see InterferonsInterferon Gamma see InterferonsInterferonsNote Peginterferon alfa interactions as for interferon alfa. Antivirals: increased risk of peripheral neuropathywhen interferon alfa given with .telbivudine. Theophylline: interferon alfa inhibits metabolism of.theophylline (consider reducing dose of theophylline)Vaccines: manufacturer of interferon gamma advisesavoid concomitant use with vaccinesIpratropium see AntimuscarinicsIrbesartan see Angiotensin-II Receptor AntagonistsIrinotecan. Antidepressants: metabolism of irinotecan acceleratedby .St John’s wort (reduced plasma concentration—avoid concomitant use)Antiepileptics: plasma concentration of irinotecan andits active metabolite reduced by carbamazepine,phenobarbital and phenytoin. Antifungals: plasma concentration of irinotecanreduced by .ketoconazole (but concentration ofactive metabolite of irinotecan increased)—avoidconcomitant use. Antipsychotics: avoid concomitant use of cytotoxicswith .clozapine (increased risk of agranulocytosis). Antivirals: metabolism of irinotecan possibly inhibitedby .atazanavir (increased risk of toxicity). Cytotoxics: plasma concentration of active metaboliteof irinotecan increased by .lapatinib—considerreducing dose of irinotecan; plasma concentration ofirinotecan possibly increased by sorafenibIronAntacids: absorption of oral iron reduced by oralmagnesium salts (as magnesium trisilicate)Antibacterials: oral iron reduces absorption of ciprofloxacin,levofloxacin, moxifloxacin, norfloxacin andofloxacin; oral iron reduces absorption of tetracyclines,also absorption of oral iron reduced bytetracyclinesBisphosphonates: oral iron reduces absorption ofbisphosphonatesCalcium Salts: absorption of oral iron reduced bycalcium saltsDopaminergics: oral iron reduces absorption ofentacapone; oral iron possibly reduces absorption oflevodopaEltrombopag: oral iron possibly reduces absorption ofeltrombopag (give at least 4 hours apart)