Use of Antifoam Agents in Indigestion: Scientific Evidence

Antifoam agents, such as simethicone, are commonly used in the management of symptoms associated with indigestion, particularly those related to excessive gas, bloating, and discomfort. The mechanism by which these agents work is physical rather than chemical: antifoam agents reduce the surface tension of gas bubbles in the gastrointestinal tract, causing them to coalesce and be expelled more easily, either by belching or passing flatus.

There is moderate scientific evidence supporting their efficacy, particularly for functional dyspepsia and conditions where gas entrapment is a prominent symptom. Clinical trials and systematic reviews have shown that simethicone can modestly reduce symptoms such as bloating and abdominal discomfort in some patients. However, evidence for their overall benefit in "indigestion" (which is a broad, non-specific term) is mixed. While some patients report symptomatic relief, large-scale meta-analyses suggest that the therapeutic benefit may be limited, and improvement may not be significantly greater than placebo in all cases.

In summary, antifoam agents are justified for use in indigestion when gas symptoms predominate, and their mechanism of action is well understood. However, the overall evidence base is moderate (rated 3/5), reflecting variability in clinical outcomes and the non-specific nature of indigestion as a diagnosis.