Diphenhydramine hydrochloride (dye fen hye' dra meen), trade name Benadryl as produced by McNeil-PPC a division of Johnson & Johnson, or Dimedrol outside the U.S. & Canada. Unisom and Nytol as sleeping pills) is an over-the-counter (OTC) antihistamine, antiemetic, sedative, and hypnotic. It may also be used for the treatment of extrapyramidal side effects of typical antipsychotics, such as the tremors that haloperidol can cause. It is a member of the ethanolamine class of antihistaminergic agents.
Diphenhydramine is also an anticholinergic and was discovered during the search for synthetic alternatives to scopolamine which would be easier to work with.[citation needed]
Diphenhydramine was one of the first known antihistamines, invented in 1943 by Dr. George Rieveschl, a former professor at the University of Cincinnati.It became the first FDA-approved prescription antihistamine in 1946.
The brand Benadryl is currently trademarked in the United States by Pfizer; however, many drug store chains and retail outlets manufacture less-costly generic versions under their own store brands.
Side effects
Like many other first-generation antihistamines, diphenhydramine is a potent anticholinergic agent. This leads to profound drowsiness as a very common side-effect, along with the possibilities of motor impairment (ataxia), dry mouth and throat, flushed skin, rapid or irregular heartbeat (tachycardia), blurred vision at nearpoint owing to lack of accommodation (cycloplegia), abnormal sensitivity to bright light (photophobia), pupil dilation (mydriasis), urinary retention (ischuria), constipation, difficulty concentrating, short-term memory loss, visual disturbances, hallucinations, irritability, itchy skin, confusion, erectile dysfunction, and delirium. Some side effects such as twitching may be delayed until the drowsiness begins to cease and the person is in more of an awakening mode. Diphenhydramine also has local anesthetic properties, and has been used for patients allergic to common local anesthetics like lidocaine.
Severe, prolonged twitching and muscle spasm have also been experienced.
The most common cardiac dysrhythmias associated with diphenhydramine overdose are sinus bradycardia, elongated S-T segment interval, and premature ventricular contraction.
Diphenhydramine is similar in its effects to dimenhydrinate (Dramamine), its 8-chlorotheophylline salt, although the latter is approximately 60% the potency in terms of required dosage and is slightly less sedating.
Some patients have an allergic reaction to diphenhydramine in the form of hives.
Since 2002 the US FDA requires special labeling: avoid using multiple products including diphenhydramine, or using topical forms to treat poison ivy urushiol-induced contact dermatitis.
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Small interfering RNA (siRNA), sometimes known as short interfering RNA or silencing RNA, is a class of 20-25 nucleotide-long double-stranded RNA molecules that play a variety of roles in biology. Most notably, siRNA is involved in the RNA interference (RNAi) pathway, where it interferes with the expression of a specific gene. In addition to their role in the RNAi pathway, siRNAs also act in RNAi-related pathways, e.g., as an antiviral mechanism or in shaping the chromatin structure of a genome; the complexity of these pathways is only now being elucidated.
siRNAs were first discovered by David Baulcombe's group in Norwich, England, as part of post-transcriptional gene silencing (PTGS) in plants. The group published their findings in Science in a paper titled "A species of small antisense RNA in posttranscriptional gene silencing in plants".Shortly thereafter, in 2001, synthetic siRNAs were shown to be able to induce RNAi in mammalian cells by Thomas Tuschl and colleagues in a paper published in Nature. This discovery led to a surge in interest in harnessing RNAi for biomedical research and drug development.
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"Seeing pink elephants" is a euphemism for drunken hallucination, caused by alcoholic hallucinosis or delirium tremens. The first recorded use of the term is by Jack London in 1913, who describes one sort of alcoholic in the autobiographical John Barleycorn as "the man whom we all know, stupid, unimaginative, whose brain is bitten numbly by numb maggots; who walks generously with wide-spread, tentative legs, falls frequently in the gutter, and who sees, in the extremity of his ecstasy, blue mice and pink elephants. He is the type that gives rise to the jokes in the funny papers." London may have derived his metaphor from the 1890s saying "being followed by pink giraffes".
A reference to pink elephants occurs in the 1941 Disney animated classicDumbo. Dumbo, having taken a drink of water from a bucket spiked with moonshine, begins to hallucinate singing and dancing "Pink Elephants on Parade".
The association between pink elephants and alcohol is reflected in the name of various alcoholic drinks. The "Pink Elephant" cocktail, made with vodka, grenadine, galliano and orange juice, is referenced in the chorus of the Madonna song 'Dear Jessie', which starts with the phrase "Pink elephants and lemonade". The Strong Bad Email episode nightlife features the fictitious "Pink Elephant Pants" drink.The Huyghe Brewery in Melle, Belgium features a pink elephant on the label of its Delirium Tremens beer and as a mouse cursor on its website.
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Kryptonite is a mineral from the Superman mythos, originating in the Superman radio show series.
The material is usually shown as having been created from the remains of Superman's native planet of Krypton, and generally has detrimental effects on Superman and other Kryptonians. The name "Kryptonite" covers a variety of forms of the substance, but usually refers to the most common "green" form.
The word Kryptonite is also used in modern speech as a synonym for Achilles' heel, the one weakness of an otherwise invulnerable hero.
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