BNF for Children 2011-2012

740 Appendix 1: Interactions BNFC 2011–2012Appendix 1: InteractionsVardenafil (continued). Antifungals: plasma concentration of vardenafilincreased by .ketoconazole—avoid concomitant use;plasma concentration of vardenafil possiblyincreased by .itraconazole—avoid concomitant use. Antivirals: plasma concentration of vardenafil possiblyincreased by fosamprenavir; plasma concentration ofvardenafil increased by .indinavir and .ritonavir—avoid concomitant use; increased risk of ventriculararrhythmias when vardenafil given with.saquinavir—avoid concomitant useCalcium-channel Blockers: enhanced hypotensiveeffect when vardenafil given with nifedipine. Grapefruit Juice: plasma concentration of vardenafilpossibly increased by .grapefruit juice—avoid concomitantuse. Nicorandil: possible increased hypotensive effect whenvardenafil given with .nicorandil—avoid concomitantuse. Nitrates: possible increased hypotensive effect whenvardenafil given with .nitrates—avoid concomitantuseVasodilator AntihypertensivesACE Inhibitors: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith ACE inhibitorsAdrenergic Neurone Blockers: enhanced hypotensiveeffect when hydralazine, minoxidil or sodium nitroprussidegiven with adrenergic neurone blockersAlcohol: enhanced hypotensive effect when hydralazine,minoxidil or sodium nitroprusside given withalcoholAldesleukin: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith aldesleukinAlpha-blockers: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith alpha-blockersAnaesthetics, General: enhanced hypotensive effectwhen hydralazine, minoxidil or sodium nitroprussidegiven with general anaestheticsAnalgesics: hypotensive effect of hydralazine,minoxidil and sodium nitroprusside antagonised byNSAIDsAngiotensin-II Receptor Antagonists: enhancedhypotensive effect when hydralazine, minoxidil orsodium nitroprusside given with angiotensin-IIreceptor antagonistsAntidepressants: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith MAOIs; enhanced hypotensive effect whenhydralazine or sodium nitroprusside given withtricyclic-related antidepressantsAntipsychotics: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith phenothiazinesAnxiolytics and Hypnotics: enhanced hypotensiveeffect when hydralazine, minoxidil or sodium nitroprussidegiven with anxiolytics and hypnoticsBeta-blockers: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith beta-blockersCalcium-channel Blockers: enhanced hypotensiveeffect when hydralazine, minoxidil or sodium nitroprussidegiven with calcium-channel blockersClonidine: enhanced hypotensive effect when hydralazine,minoxidil or sodium nitroprusside given withclonidineCorticosteroids: hypotensive effect of hydralazine,minoxidil and sodium nitroprusside antagonised bycorticosteroidsDiazoxide: enhanced hypotensive effect when hydralazine,minoxidil or sodium nitroprusside given withdiazoxideDiuretics: enhanced hypotensive effect when hydralazine,minoxidil or sodium nitroprusside given withdiureticsVasodilator Antihypertensives (continued)Dopaminergics: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith levodopaMethyldopa: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith methyldopaMoxisylyte: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith moxisylyteMoxonidine: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith moxonidineMuscle Relaxants: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith baclofen; enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith tizanidineNicorandil: possible enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith nicorandilNitrates: enhanced hypotensive effect when hydralazine,minoxidil or sodium nitroprusside given withnitratesOestrogens: hypotensive effect of hydralazine,minoxidil and sodium nitroprusside antagonised byoestrogensProstaglandins: enhanced hypotensive effect whenhydralazine, minoxidil or sodium nitroprusside givenwith alprostadilVasodilator Antihypertensives: enhanced hypotensiveeffect when hydralazine given with minoxidil orsodium nitroprusside; enhanced hypotensive effectwhen minoxidil given with sodium nitroprussideVecuronium see Muscle RelaxantsVenlafaxine. Analgesics: increased risk of bleeding when venlafaxinegiven with .NSAIDs or .aspirin; possibleincreased serotonergic effects when venlafaxinegiven with tramadol. Anticoagulants: venlafaxine possibly enhances anticoagulanteffect of .warfarin. Antidepressants: possible increased serotonergiceffects when venlafaxine given with St John’s wort,duloxetine or mirtazapine; enhanced CNS effects andtoxicity when venlafaxine given with .MAOIs (venlafaxineshould not be started until 2 weeks afterstopping MAOIs, avoid MAOIs for 1 week afterstopping venlafaxine); after stopping SSRI-relatedantidepressants do not start .moclobemide for atleast 1 week. Antimalarials: avoidance of antidepressants advised bymanufacturer of .artemether/lumefantrine. Antipsychotics: venlafaxine increases plasma concentrationof .clozapine and haloperidolAtomoxetine: possible increased risk of convulsionswhen antidepressants given with atomoxetine. Dopaminergics: caution with venlafaxine advised bymanufacturer of entacapone; increased risk ofhypertension and CNS excitation when venlafaxinegiven with .selegiline (selegiline should not bestarted until 1 week after stopping venlafaxine, avoidvenlafaxine for 2 weeks after stopping selegiline)5HT 1 Agonists: possible increased serotonergic effectswhen venlafaxine given with 5HT 1 agonistsLithium: possible increased serotonergic effects whenvenlafaxine given with lithiumVerapamil see Calcium-channel BlockersVigabatrin. 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: vigabatrin reduces plasma concentrationof phenytoin