While antacids and antiallergic drugs interfere with the function of histamines,why do these not interfere with the function of each other?

(N/A) Specific drugs bind to specific receptors. Antacids (such as cimetidine) are designed to bind to histamine receptors in the stomach wall to prevent acid secretion,while antiallergic drugs (such as brompheniramine) bind to different histamine receptors involved in allergic reactions. Because these drugs target different types of receptors,they do not interfere with each other's functions.