BNF for Children 2011-2012

BNFC 2011–2012 Appendix 1: Interactions 739Ulipristal (continued). Progestogens: ulipristal possibly reduces contraceptiveeffect of .progestogens. Ulcer-healing Drugs: manufacturer of ulipristal advisesavoid concomitant use with .histamine H 2 -antagonists and .proton pump inhibitors (plasmaconcentration of ulipristal possibly reduced)Ursodeoxycholic Acid see Bile AcidsUstekinumab. Vaccines: avoid concomitant use of ustekinumab withlive .vaccines (see p. 599)VaccinesNote For a general warning on live vaccines and high dosesof corticosteroids or other immunosuppressive drugs, seep. 599; for advice on live vaccines and immunoglobulins, seeunder Normal Immunoglobulin, p. 622. Abatacept: avoid concomitant use of live vaccines with.abatacept (see p. 599). Adalimumab: avoid concomitant use of live vaccineswith .adalimumab (see p. 599). Anakinra: avoid concomitant use of live vaccines with.anakinra (see p. 599)Antibacterials: oral typhoid vaccine inactivated byantibacterials—see p. 620Anticoagulants: influenza vaccine possibly enhancesanticoagulant effect of warfarinAntiepileptics: influenza vaccine enhances effects ofphenytoinAntimalarials: oral typhoid vaccine inactivated byantimalarials—see p. 620. Certolizumab pegol: avoid concomitant use of livevaccines with .certolizumab pegol (see p. 599). Corticosteroids: immune response to vaccinesimpaired by high doses of .corticosteroids, avoidconcomitant use with live vaccines (see p. 599). Etanercept: avoid concomitant use of live vaccineswith .etanercept (see p. 599). Golimumab: avoid concomitant use of live vaccineswith .golimumab (see p. 599). Infliximab: avoid concomitant use of live vaccines with.infliximab (see p. 599)Interferons: avoidance of vaccines advised by manufacturerof interferon gamma. Leflunomide: avoid concomitant use of live vaccineswith .leflunomide (see p. 599)Theophylline: influenza vaccine possibly increasesplasma concentration of theophylline. Tocilizumab: avoid concomitant use of live vaccineswith .tocilizumab (see p. 599). Ustekinumab: avoid concomitant use of live vaccineswith .ustekinumab (see p. 599)Valaciclovir see AciclovirValganciclovir see GanciclovirValproateAnalgesics: effects of valproate enhanced by aspirin. Antibacterials: metabolism of valproate possiblyinhibited by erythromycin (increased plasma concentration);plasma concentration of valproatereduced by .carbapenems—avoid concomitant useAnticoagulants: valproate possibly enhances anticoagulanteffect of coumarins. Antidepressants: anticonvulsant effect of antiepilepticspossibly antagonised by MAOIs and .tricyclic-relatedantidepressants (convulsive threshold lowered); anticonvulsanteffect of antiepileptics antagonised by.SSRIs and .tricyclics (convulsive thresholdlowered); avoid concomitant use of antiepilepticswith .St John’s wortAntiepileptics: plasma concentration of valproatereduced by carbamazepine, also plasma concentrationof active metabolite of carbamazepine increased;valproate possibly increases plasma concentration ofethosuximide; valproate increases plasma concentrationof lamotrigine; valproate sometimes reducesplasma concentration of an active metabolite ofoxcarbazepine; valproate increases plasma concentrationof phenobarbital (also plasma concentrationof valproate reduced); valproate increases or possiblydecreases plasma concentration of phenytoin, alsoValproateAntiepileptics (continued)plasma concentration of valproate reduced; valproatepossibly increases plasma concentrationof rufinamide (reduce dose of rufinamide);hyperammonaemia and CNS toxicity reportedwhen valproate given with topiramate. Antimalarials: possible increased risk of convulsionswhen antiepileptics given with chloroquine andhydroxychloroquine; anticonvulsant effect of antiepilepticsantagonised by .mefloquine. Antipsychotics: anticonvulsant effect of antiepilepticsantagonised by .antipsychotics (convulsive thresholdlowered); valproate possibly increases or decreasesplasma concentration of clozapine; increased risk ofside-effects including neutropenia when valproategiven with .olanzapine; valproate possibly increasesplasma concentration of quetiapineAntivirals: valproate possibly increases plasma concentrationof zidovudine (increased risk of toxicity)Anxiolytics and Hypnotics: plasma concentration ofvalproate possibly increased by clobazam; increasedrisk of side-effects when valproate given with clonazepam;valproate possibly increases plasma concentrationof diazepam and lorazepamBupropion: valproate inhibits the metabolism ofbupropionCytotoxics: valproate increases plasma concentrationof temozolomideLipid-regulating Drugs: absorption of valproate possiblyreduced by colestyramineOestrogens: plasma concentration of valproate possiblyreduced by ethinylestradiol. Orlistat: possible increased risk of convulsions whenantiepileptics given with .orlistatSodium Benzoate: valproate possibly reduces effectsof sodium benzoateSodium Phenylbutyrate: valproate possibly reduceseffects of sodium phenylbutyrate. Ulcer-healing Drugs: metabolism of valproate inhibitedby .cimetidine (increased plasma concentration)Valsartan see Angiotensin-II Receptor AntagonistsVancomycinAnaesthetics, General: hypersensitivity-like reactionscan occur when intravenous vancomycin given withgeneral anaesthetics. Antibacterials: increased risk of nephrotoxicity andototoxicity when vancomycin given with.aminoglycosides, capreomycin or colistimethatesodium; increased risk of nephrotoxicity whenvancomycin given with polymyxinsAntifungals: possible increased risk of nephrotoxicitywhen vancomycin given with amphotericin. Ciclosporin: increased risk of nephrotoxicity whenvancomycin given with .ciclosporinCytotoxics: increased risk of nephrotoxicity and possiblyof ototoxicity when vancomycin given withcisplatin. Diuretics: increased risk of otoxicity when vancomycingiven with .loop diureticsLipid-regulating Drugs: effects of oral vancomycinantagonised by colestyramine. Muscle Relaxants: vancomycin enhances effects of.suxamethoniumTacrolimus: possible increased risk of nephrotoxicitywhen vancomycin given with tacrolimusVaccines: antibacterials inactivate oral typhoidvaccine—see p. 620Vardenafil. Alpha-blockers: enhanced hypotensive effect whenvardenafil given with .alpha-blockers (excludestamsulosin)—separate doses by 6 hours—see alsounder Phosphodiesterase type-5 inhibitors, BNFsection 7.4.5Antibacterials: plasma concentration of vardenafilincreased by erythromycin (reduce dose of vardenafil)Appendix 1: Interactions