BNF for Children 2011-2012

666 Appendix 1: Interactions BNFC 2011–2012Appendix 1: InteractionsAntidiabetics (continued)Deferasirox: plasma concentration of repaglinideincreased by deferasiroxDiazoxide: hypoglycaemic effect of antidiabeticsantagonised by diazoxideDiuretics: hypoglycaemic effect of antidiabetics antagonisedby loop diuretics and thiazides and relateddiureticsHormone Antagonists: requirements for insulin, metformin,repaglinide and sulfonylureas possiblyreduced by lanreotide; requirements for insulin,metformin, repaglinide and sulfonylureas possiblyreduced by octreotideLeflunomide: hypoglycaemic effect of tolbutamidepossibly enhanced by leflunomide. Lipid-regulating Drugs: absorption of glibenclamidereduced by colesevelam; hypoglycaemic effect ofacarbose possibly enhanced by colestyramine;hypoglycaemic effect of nateglinide possiblyenhanced by gemfibrozil; increased risk of severehypoglycaemia when repaglinide given with.gemfibrozil—avoid concomitant use; plasma concentrationof glibenclamide possibly increased byfluvastatin; may be improved glucose tolerance andan additive effect when insulin or sulfonylureas givenwith fibratesOestrogens: hypoglycaemic effect of antidiabeticsantagonised by oestrogensOrlistat: avoidance of acarbose advised by manufacturerof orlistatPancreatin: hypoglycaemic effect of acarbose antagonisedby pancreatinProgestogens: hypoglycaemic effect of antidiabeticsantagonised by progestogens. Sulfinpyrazone: effects of sulfonylureas enhanced by.sulfinpyrazoneTestosterone: hypoglycaemic effect of antidiabeticspossibly enhanced by testosteroneUlcer-healing Drugs: excretion of metformin reducedby cimetidine (increased plasma concentration);hypoglycaemic effect of sulfonylureas enhanced bycimetidineAntiepileptics see Carbamazepine, Eslicarbazepine,Ethosuximide, Gabapentin, Lacosamide, Lamotrigine,Levetiracetam, Oxcarbazepine, Phenobarbital,Phenytoin, Rufinamide, Stiripentol, Tiagabine,Topiramate, Valproate, Vigabatrin, and ZonisamideAntifungals see Amphotericin; Antifungals, Imidazole;Antifungals, Triazole; Caspofungin; Flucytosine;Griseofulvin; Micafungin; TerbinafineAntifungals, ImidazoleAliskiren: ketoconazole increases plasma concentrationof aliskirenAlpha-blockers: ketoconazole possibly increasesplasma concentration of alfuzosin. Analgesics: ketoconazole inhibits metabolism of.buprenorphine (reduce dose of buprenorphine)Antacids: absorption of ketoconazole reduced byantacids. Anti-arrhythmics: increased risk of ventricular arrhythmiaswhen ketoconazole given with.disopyramide—avoid concomitant use; ketoconazoleincreases plasma concentration of.dronedarone—avoid concomitant use. Antibacterials: metabolism of ketoconazole acceleratedby .rifampicin (reduced plasma concentration),also plasma concentration of rifampicin may bereduced by ketoconazole; plasma concentration ofketoconazole possibly reduced by isoniazid; avoidanceof concomitant ketoconazole in severe renaland hepatic impairment advised by manufacturer of.telithromycin. Anticoagulants: ketoconazole enhances anticoagulanteffect of .coumarins; miconazole enhances anticoagulanteffect of .coumarins (miconazole oral geland possibly vaginal formulations absorbed); ketoconazoleincreases plasma concentration of.rivaroxaban—avoid concomitant useAntifungals, Imidazole (continued). Antidepressants: avoidance of imidazoles advised bymanufacturer of .reboxetine; ketoconazole increasesplasma concentration of mirtazapine. Antidiabetics: miconazole enhances hypoglycaemiceffect of .gliclazide and .glipizide—avoid concomitantuse; miconazole increases plasma concentrationof .sulfonylureas. Antiepileptics: ketoconazole and miconazole possiblyincrease plasma concentration of carbamazepine;plasma concentration of ketoconazole reduced by.phenytoin; miconazole enhances anticonvulsanteffect of .phenytoin (plasma concentration ofphenytoin increased)Antifungals: imidazoles possibly antagonise effects ofamphotericin. Antihistamines: manufacturer of loratadine advisesketoconazole possibly increases plasma concentrationof loratadine; imidazoles possibly inhibit metabolismof .mizolastine (avoid concomitant use);ketoconazole inhibits metabolism of .mizolastine—avoid concomitant use; ketoconazole increasesplasma concentration of rupatadine. Antimalarials: avoidance of imidazoles advised bymanufacturer of .artemether/lumefantrine; ketoconazoleincreases plasma concentration of mefloquineAntimuscarinics: absorption of ketoconazole reducedby antimuscarinics; ketoconazole increases plasmaconcentration of darifenacin—avoid concomitantuse; manufacturer of fesoterodine advises dosereduction when ketoconazole given with fesoterodine—consultfesoterodine product literature; ketoconazoleincreases plasma concentration ofsolifenacin; avoidance of ketoconazole advised bymanufacturer of tolterodine. Antipsychotics: ketoconazole inhibits metabolism of.aripiprazole (reduce dose of aripiprazole); increasedrisk of ventricular arrhythmias when imidazoles givenwith .pimozide—avoid concomitant use; imidazolespossibly increase plasma concentration of quetiapine(reduce dose of quetiapine). Antivirals: plasma concentration of both drugsincreased when ketoconazole given with darunavir;plasma concentration of ketoconazole increased byfosamprenavir (also plasma concentration of fosamprenavirpossibly increased); ketoconazole increasesplasma concentration of .indinavir and .maraviroc(consider reducing dose of indinavir and maraviroc);plasma concentration of ketoconazole reduced by.nevirapine—avoid concomitant use; combination ofketoconazole with .ritonavir may increase plasmaconcentration of either drug (or both); imidazolespossibly increase plasma concentration of saquinavir;ketoconazole increases plasma concentration ofsaquinavir. Anxiolytics and Hypnotics: ketoconazole increasesplasma concentration of alprazolam; ketoconazoleincreases plasma concentration of .midazolam (riskof prolonged sedation)Aprepitant: ketoconazole increases plasma concentrationof aprepitantBosentan: ketoconazole increases plasma concentrationof bosentan. Calcium-channel Blockers: ketoconazole inhibitsmetabolism of .felodipine (increased plasma concentration);avoidance of ketoconazole advised bymanufacturer of lercanidipine; ketoconazole possiblyinhibits metabolism of dihydropyridines (increasedplasma concentration). Ciclosporin: ketoconazole inhibits metabolism of.ciclosporin (increased plasma concentration);miconazole possibly inhibits metabolism of.ciclosporin (increased plasma concentration)Cilostazol: ketoconazole increases plasma concentrationof cilostazol (consider reducing dose of cilostazol)Cinacalcet: ketoconazole inhibits metabolism of cinacalcet(increased plasma concentration)