Ventolin Diskus - GlaxoSmithKline

DRUG INTERACTIONSDrug-Drug InteractionsTable 2-Established or Potential Drug-Drug InteractionsProper name Ref Effect Clinical commentMonoamineoxidase inhibitors ortricyclicantidepressants.Other inhaledsympathomimeticbronchodilators orepinephrine.Beta-blockersDiureticsDigoxinCSCSCSCSCSMay potentiate action ofsalbutamol on cardiovascularsystem.May lead to deleteriouscardiovascular effects.May effectively antagonise theaction of salbutamol.May lead to ECG changesand/or hypokalemia, althoughthe clinical significance ofthese effects is not known.May lead to decrease in serumdigoxin levels. The clinicalsignificance of these findingsfor patients with obstructiveairways disease who arereceiving salbutamol sulphateand digoxin on a chronic basisis unclear.Legend: C = Case Study; CT = Clinical Trial; T = TheoreticalSalbutamol should be administered withextreme caution to patients being treatedwith monoamine oxidase inhibitors ortricyclic antidepressants.Other inhaled sympathomimeticbronchodilators or epinephrine shouldnot be used concomitantly withsalbutamol sulphate. If additionaladrenergic drugs are to be administeredby any route to the patient using inhaledsalbutamol sulphate, the adrenergicdrugs should be used with caution.Such concomitant use must beindividualized and not given on a routinebasis. If regular coadministration isrequired then alternative therapy must beconsidered.Beta-adrenergic blocking drugs,especially the non-cardioselective ones,such as propranolol, should not usuallybe prescribed together.The ECG changes and/or hypokalemiathat may result from the administrationof non-potassium sparing diuretics (suchas loop or thiazide diuretics) can beacutely worsened by beta-agonists,especially when the recommended doseof the beta-agonist is exceeded. Cautionis advised in the coadministration ofbeta-agonists with non-potassiumsparing diuretics.Mean decreases of 16-22% in serumdigoxin levels were demonstrated aftersingle dose intravenous and oraladministration of salbutamol,respectively, to normal volunteers whohad received digoxin for 10 days. Itwould be prudent to carefully evaluateserum digoxin levels in patients who arecurrently receiving digoxin andsalbutamol sulphate.October 03, 2007Page 9 of 23