In children suffering from asthma, there is an increased prevalence of GERD. Omeprazole in sufficient doses was found to improve the control of asthma.

A prospective study was carried to explore efficacy of gastroesophageal reflux disease (GERD) therapy in mitigating asthma in poorly controlled asthmatic children. 

The study recruited 102 asthmatic children (age 4 to 16 years). Utilizing pH monitoring, the presence of acid reflux was checked. In total, 59 (57.8%) participants had acid reflux. GERD subjects were randomized to either the omeprazole group that received omeprazole for 6 months or the control group that did not receive any treatment.

The score of children asthma control test after six months was the study's endpoint. With the help of pH monitoring, the acid suppression was checked at the end of therapy. Following therapy, children having persistent acid reflux were given high doses of proton-pump inhibitors (PPI) and therefore were again reassessed six months later.

GERD was considerably more common in boys. Administration of omeprazole in sufficient doses was found to improve the management of asthma in five children out of six (84.8 vs 11.5). Three factors such as male gender, normal birth weight, and a positive prick-test were statistically linked with asthma control improvement after PPI treatment.

In the multivariate assessment, these factors were not satisfactorily precise or were not confirmed. The probability of a causal relationship between asthma and acid reflux, troublesome to highlight with pH monitoring, was found to be poor. 

Omeprazole effectively controls asthma in asthmatic children having GERD, thus, indicating the possible advantage of an efficient GERD therapy in improving asthma control.