A reflux suppressant is any one of a number of drugs used to combat oesophageal reflux.
[1][2] Commonly, following ingestion a 'raft' of alginic acid is created, floating on the stomach contents by carbon dioxide released by the drug.
This forms a mechanical barrier to further reflux.
Some preparations also contain antacids to protect the oesophagus.
[3] Reflux can also be coincidentally reduced by the motility stimulants and antidopaminergics.