# How does cough medicine work?

**URL:** <https://boards.straightdope.com/t/how-does-cough-medicine-work/188060>\
**Category:** Factual Questions\
**Created:** [July 12, 2003, 11:02pm UTC](https://boards.straightdope.com/t/how-does-cough-medicine-work/188060 "2003-07-12T23:02:47Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![ricksummon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ricksummon/32/3333_2.png) [@ricksummon](https://boards.straightdope.com/u/ricksummon)\
**Post date:** [July 12, 2003, 11:02pm UTC](https://boards.straightdope.com/t/how-does-cough-medicine-work/188060/1 "2003-07-12T23:02:47Z")

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Every kind of over-the-counter cough medicine has the same active ingredient: Dextromethorphan HBr (5-15 mg/dose). Why do people cough when they get a cold, and what does this drug do to stop it?

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**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\
**Post date:** [July 12, 2003, 11:39pm UTC](https://boards.straightdope.com/t/how-does-cough-medicine-work/188060/2 "2003-07-12T23:39:28Z")

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There is some question as to how effective OTC cough medicines really are:

[http://content.health.msn.com/content/article/18/1689\_51929.htm](http://content.health.msn.com/content/article/18/1689_51929.htm)

Although, there is always the placebo effect, which should never be underestimated.