Pressure-equalizing earplugs (like EarPlanes) are effective for many travelers, though their primary function is to slow down the rate of pressure change rather than eliminate it. They contain a tiny ceramic filter that acts as a "buffer," allowing the air pressure in the ear canal to adjust more gradually during the rapid ascent and descent of a flight. Scientific studies, including those on PubMed, show mixed results; while they significantly reduce the sharp "stabbing" pain associated with barotrauma, they do not always prevent the sensation of "clogged" ears entirely. For the best results, they must be inserted before the cabin door closes and kept in until the plane has reached cruising altitude, then reinserted 30–45 minutes before landing. They are particularly useful for children or those flying with a mild cold, as they give the Eustachian tubes more time to react. However, they should be used alongside other techniques like yawning, swallowing, or chewing gum.