ABSTRACT: Background:In April 2017 the Mexican Asthma Guidelines (GUIMA) were published. Before the launch, physicians' knowledge was explored related to key issues of the guideline. Methods:A SurveyMonkey® survey was sent out to board-certified physicians of 5 medical specialties treating asthma. Replies were analyzed per specialty against the GUIMA evidence-based recommendations. We present the treatment part here. Results:A total of 364 allergists (ALLERG), 161 pulmonologists (PULM), 34 ENTs, 239 pediatricians (PED) and 62 general practitioners (GPs) replied to the survey and 247-83-14-135-37 respectively finished it. Spirometry is not routinely indicated when asthma is very probable by ALLERG 54%, PULM 47%, ENT 39%, PED 65%, GP 64%. A fictitious case proposed to the physicians with intermittent asthma was erroneously treated with ICS by ALLERG 9%, PULM 11%, ENT 28%, PED 10%, GP 11%. The mild persistent case received mistakenly ICS-LABA by ALLERG 25%, PULM 26%, ENT 33%, PED 27%, GP 23%. The first-line option for moderate persistent asthma was ICS(median dose) instead of ICS(low)+LABA for ALLERG 29%, PULM 25%, ENT 17%, PED 27%, GP 23% and in severe asthma maintenance treatment PULM20%, ALLERG-ENT-PED-GP 22-34% failed to indicate LABA. Concerning the guidelines' recommendation to use one inhaler for maintenance & rescue in moderate-to-severe asthma, PULM45%, ALLERG-ENT-PED-GP 56-80% (p < 0.00001), erroneously indicated ICS-salmeterol could be used, instead of ICS-formoterol. Oral ?2 or theophylline are no longer recommended, but PULM 37% and ALLERG-ENT-PED-GP 42-62% (p < 0.01) still indicate their use. In severe asthma 61-73% of physicians consider adding LTRA to the treatment; only PULM38%, OTHERS12-25% consider adding tiotropium (p < 0.001) and 3-17% consider adding omalizumab, both guideline recommended add-ons. As for asthma in pregnancy, most surveyed are not aware budesonide is the 1st line option ICS. Finally, 81-97% of the group-members recognized allergen immunotherapy, as a viable add-on, in line with GINA/GEMA/GUIMA recommendations. Conclusions:An online survey could detect knowledge-gaps related to asthma treatment. Interestingly, surveyed physicians tended to over-treat the milder asthma cases, thus clearly leaving room for cost-savings. Caution should be taken in the promotion of the SMART (single-maintenance-and-reliever-treatment) approach, which can only be done with ICS-formoterol. Many physicians opt for other combinations not apt for this approach. Among all surveyed specialties there is ample room for improvement in mild and severe asthma management.