Explanation: Brand names are proper nouns. For example imagine a counter with Allegra, Advil, and Tums; and then someone tells you to "go take that medicine on the counter". You would most likely be confused as to which one they're referring to. However, if someone was to instead say "go take that Advil on the counter", you would most likely be less confused as to which one they're referring to.
See how by saying "Advil" instead of "medicine" it makes the sentence and what the person's referring to clearer and more specific. That's what proper nouns do.
Brand names being proper nouns is what stops people from taking Tums when they really needed an Advil.
