phe·​no·​bar·​bi·​tal | \ ˌfē-nō-ˈbär-bə-ˌtȯl How to pronounce phenobarbital (audio) \

Definition of phenobarbital

: a crystalline barbiturate C12H12N2O3 used as a hypnotic, sedative, and anticonvulsant

Examples of phenobarbital in a Sentence

Recent Examples on the Web Mandell’s 5-year-old Labradoodle, Frankie Feldman, was diagnosed with the disorder last year and put on phenobarbital and Keppra by his vet. Susan Spillman, Los Angeles Times, "Why some pet owners are turning to CBD to treat their ailing animals," 4 Oct. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'phenobarbital.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of phenobarbital

1919, in the meaning defined above

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The first known use of phenobarbital was in 1919

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Cite this Entry

“Phenobarbital.” The Dictionary, Merriam-Webster Inc., Accessed 23 January 2020.

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phe·​no·​bar·​bi·​tal | \ ˌfē-nō-ˈbär-bə-ˌtȯl, -tȧl How to pronounce phenobarbital (audio) \

Medical Definition of phenobarbital

: a crystalline barbiturate C12H12N2O3 that is used orally or is administered by injection in the form of its sodium salt C12H11N2NaO3 as a hypnotic and sedative — see luminal

Comments on phenobarbital

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out of the ordinary or unreasonable

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