BNF for Children 2011-2012

BNFC 2011–2012 Appendix 1: Interactions 693Efavirenz. Antipsychotics (continued)concentration of .pimozide (increased risk ofventricular arrhythmias—avoid concomitant use). Antivirals: avoidance of efavirenz advised by manufacturerof .atazanavir (plasma concentration ofatazanavir reduced); efavirenz reduces plasma concentrationof darunavir, fosamprenavir and indinavir;efavirenz possibly reduces plasma concentration of.etravirine—avoid concomitant use; efavirenzreduces plasma concentration of .lopinavir—considerincreasing dose of lopinavir; efavirenz possiblyreduces plasma concentration of .maraviroc—considerincreasing dose of maraviroc; plasma concentrationof efavirenz reduced by nevirapine; toxicity ofefavirenz increased by ritonavir, monitor liver functiontests; efavirenz significantly reduces plasmaconcentration of saquinavir. Anxiolytics and Hypnotics: increased risk of prolongedsedation when efavirenz given with .midazolam—avoid concomitant useCalcium-channel Blockers: efavirenz reduces plasmaconcentration of diltiazem. Ciclosporin: efavirenz possibly reduces plasma concentrationof .ciclosporin. Ergot Alkaloids: increased risk of ergotism whenefavirenz given with .ergot alkaloids—avoid concomitantuseGrapefruit Juice: plasma concentration of efavirenzpossibly increased by grapefruit juiceLipid-regulating Drugs: efavirenz reduces plasmaconcentration of atorvastatin, pravastatin andsimvastatin. Progestogens: efavirenz possibly reduces contraceptiveeffect of .progestogens. Tacrolimus: efavirenz possibly affects plasma concentrationof .tacrolimusEletriptan see 5HT 1 AgonistsEltrombopagAntacids: absorption of eltrombopag reduced byantacids (give at least 4 hours apart)Antivirals: plasma concentration of eltrombopag possiblyreduced by lopinavirCalcium Salts: absorption of eltrombopag possiblyreduced by calcium salts (give at least 4 hours apart)Dairy Products: absorption of eltrombopag possiblyreduced by dairy products (give at least 4 hoursapart)Iron: absorption of eltrombopag possibly reduced byoral iron (give at least 4 hours apart). Lipid-regulating Drugs: eltrombopag increases plasmaconcentration of .rosuvastatin (consider reducingdose of rosuvastatin)Selenium: absorption of eltrombopag possibly reducedby selenium (give at least 4 hours apart)Zinc: absorption of eltrombopag possibly reduced byzinc (give at least 4 hours apart)EmtricitabineAntivirals: manufacturer of emtricitabine advises avoidconcomitant use with lamivudineEnalapril see ACE InhibitorsEnoxaparin see HeparinsEnoximone see Phosphodiesterase InhibitorsEntacapone. Anticoagulants: entacapone enhances anticoagulanteffect of .warfarin. Antidepressants: manufacturer of entacapone advisescaution with moclobemide, paroxetine, tricyclics andvenlafaxine; avoid concomitant use of entacaponewith non-selective .MAOIsDopaminergics: entacapone possibly enhances effectsof apomorphine; entacapone possibly reducesplasma concentration of rasagiline; manufacturer ofentacapone advises max. dose of 10 mg selegiline ifused concomitantlyIron: absorption of entacapone reduced by oral ironMemantine: effects of dopaminergics possiblyenhanced by memantineEntacapone (continued)Methyldopa: entacapone possibly enhances effects ofmethyldopa; antiparkinsonian effect of dopaminergicsantagonised by methyldopaSympathomimetics: entacapone possibly enhanceseffects of adrenaline (epinephrine), dobutamine,dopamine and noradrenaline (norepinephrine)Enteral Foods. Anticoagulants: the presence of vitamin K in someenteral feeds can antagonise the anticoagulant effectof .coumarins and .phenindioneAntiepileptics: enteral feeds possibly reduce absorptionof phenytoinEphedrine see SympathomimeticsEpinephrine (adrenaline) see SympathomimeticsEpirubicin. Antipsychotics: avoid concomitant use of cytotoxicswith .clozapine (increased risk of agranulocytosis). Ciclosporin: plasma concentration of epirubicinincreased by .ciclosporin. Ulcer-healing Drugs: plasma concentration of epirubicinincreased by .cimetidineEplerenone see DiureticsEprosartan see Angiotensin-II Receptor AntagonistsEptifibatideIloprost: increased risk of bleeding when eptifibatidegiven with iloprostErgometrine see Ergot AlkaloidsErgot AlkaloidsAnaesthetics, General: effects of ergometrine on theparturient uterus reduced by halothane. Antibacterials: increased risk of ergotism when ergotamineand methysergide given with .macrolides or.telithromycin—avoid concomitant use; increasedrisk of ergotism when ergotamine and methysergidegiven with tetracyclinesAntidepressants: possible risk of hypertension whenergotamine and methysergide given with reboxetine. Antifungals: increased risk of ergotism when ergotamineand methysergide given with .imidazoles or.triazoles—avoid concomitant use. Antivirals: plasma concentration of ergot alkaloidspossibly increased by .atazanavir—avoid concomitantuse; increased risk of ergotism when ergotalkaloids given with .efavirenz—avoid concomitantuse; increased risk of ergotism when ergotamine andmethysergide given with .fosamprenavir, .indinavir,.nelfinavir, .ritonavir or .saquinavir—avoid concomitantuseBeta-blockers: increased peripheral vasoconstrictionwhen ergotamine and methysergide given with betablockers. 5HT 1 Agonists: increased risk of vasospasm whenergotamine and methysergide given with .almotriptan,.rizatriptan, .sumatriptan or .zolmitriptan (avoidergotamine and methysergide for 6 hours afteralmotriptan, rizatriptan, sumatriptan or zolmitriptan,avoid almotriptan, rizatriptan, sumatriptan or zolmitriptanfor 24 hours after ergotamine and methysergide);increased risk of vasospasm whenergotamine and methysergide given with .eletriptan,.frovatriptan or .naratriptan (avoid ergotamine andmethysergide for 24 hours after eletriptan,frovatriptan or naratriptan, avoid eletriptan,frovatriptan or naratriptan for 24 hours after ergotamineand methysergide)Sympathomimetics: increased risk of ergotism whenergotamine and methysergide given with sympathomimetics. Ulcer-healing Drugs: increased risk of ergotism whenergotamine and methysergide given with.cimetidine—avoid concomitant useErgotamine and Methysergide see Ergot AlkaloidsErlotinib. Analgesics: increased risk of bleeding when erlotinibgiven with .NSAIDsAppendix 1: Interactions