AIM:Toevaluatethelong-termresponsetothefixedcombinationofdorzolamide/timololinpatientswithprimaryopenangleglaucoma(POAG)andtheadditionofotherintraocularpressure(IOP)loweringmedicationssuchasprostaglandinanalogsandbrimonidine.METHODS:Aretrospective,non-randomized,anddescriptiveclinicalstudywasperformedwith182eyesdiagnosedwithPOAG.Patientswerepidedintothreegroups:agroupwithfixedcombinationofdorzolamide/timololonly,asecondgroupwithprostaglandinanalogsplusfixedcombinationofdorzolamide/timolol,andathirdgroupwiththeadditionofbrimonidinetothesamefixedcombination.IOPdataweregatheredretrospectivelyandthedifferencesbetweengroupswerecalculated.RESULTS:IOPwasreducedsatisfactorilyinallthreegroups;however,aprogressiveIOPreductionwasnotedinthegroupwiththefixedcombinationplusprostaglandinanalogs.Inthisgroup,aprogressive,significantandmorehomogeneousresponseofthereductionwasnotedincomparisonwiththeothergroups.CONCLUSION:IOPreductionwasefficaciousinallthreegroups.TheadditionofprostaglandinanalogsshowedprogressiveIOPreduction,progressiveresponseandabsenceoflong-termdrift.Brimonidinedidnotshowasignificantadditiveeffect.