Why Do Some Drugs Make Your Pupils Wider?

How do your pupils work and why do some substances make them dilate?

Written by: Jill Teige
Hosted by: Hank Green

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Sources:
https://www.ncbi.nlm.nih.gov/pubmedhe...
http://bjo.bmj.com/content/bjophthalm...
http://eyewiki.aao.org/Pharmacologic_...
https://www.scientificamerican.com/ar...
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https://www.healthline.com/health/ant...
http://www.pamf.org/asthma/medication...
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https://www.ncbi.nlm.nih.gov/pubmedhe...
http://scienceline.ucsb.edu/getkey.ph...
https://www.ncbi.nlm.nih.gov/pmc/arti...
https://books.google.com/books?id=mDL...
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http://www.jefferson.edu/university/j...
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https://commons.wikimedia.org/wiki/Fi...
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https://www.flickr.com/photos/medical...