In Mexico, no effort has been made to estimate a nationwide prevalence rate
of asthma. However, in the last 10 years several local studies have been c
arried out that analyze the same age cohort that have similar methodologica
l features, enabling us to have a reference from which to look at childhood
asthma prevalence in Mexico. Applying statistical analysis to all the surv
eys, we obtained a prevalence rate of childhood asthma of 11.85% with a con
fidence interval of 11.32% and 12.38%. We have data that let us know that t
he prevalence of asthma in Mexico is increasing as in other countries. The
comportment of asthma medication is changing very slowly, at least in the c
ommercial market.