Out-of-control libido or drug habit? Take Nervine. Nervous, excitable, wakeful, or restless? Take Nervine. Over-the-counter Nervine wasn't a wonder drug, just a cocktail of the oldest class of sedatives - inorganic bromides.
Nervine contained the most commonly used bromides - sodium bromide (NaBr), potassium bromide (KBr), and ammonium bromide (NH4Br). These particular bromides were once so popular that only aspirin sold better. The use of bromides to treat "nerves" was so prevalent that 'bromide' entered the lexicon of common speech. Instead of "calm down", people were instructed to "take a bromide". Instead of calling someone a 'bore', the term 'bromide' was a used to denote "a commonplace or tiresome person".
Bromides may owe their sedative effect to a family connection. The element bromine is in the same chemical family as the element chlorine – the halogens. Being a chemical family, chlorine and bromine have similar properties. Both form single, negatively charged ions (monovalent anions) via oxidation-reduction reactions - chloride (Cl-) and bromide (Br-).
Chloride is found in nearly all of our cells, having its own set cell membrane-crossing highways (chlorine channel). The regulated flow of chloride (as hydrated chloride) across neuron membranes is key to communication between neurons. Being family and all, bromide (as hydrated bromide) can travel along chloride's highways. But hydrated bromide is a teeny bit smaller than hydrated chloride, allowing hydrated bromide to get into cells faster than hydrated chloride. A flood of anions, such as bromide or chloride, into a neuron makes it more negative than it would be at rest, a state called 'hyperpolarization'. It's hard for other neutrons to stimulate - talk to - hyperpolarized neurons. Less neuron stimulation can translate to a feeling of calm.
A temporary calm that came with a price beyond the one listed on the price tag. Turns out, the level of bromide needed to sedate was pretty close to bromine's toxicity level. Plus, people were using products like Nervine a too regularly to "settle their nerves". When bromides were the most popular, bromine toxicity ("bromism") cases were at a high.
The classic symptoms of bromism include alteration in central nervous system functioning with headache, irritability, fatigue, slurred speech, ataxia, emotional instability, tremor and hallucinations all being reported.
[Horowitz, B. (1997)]
There were even reports of bromide-induced coma, dubbed 'The Bromide Sleep'. Taking advantage of the swapability of chloride and bromide, bromism was often treated by loading a person with saline (sodium chloride solution).
Bromism, along with the development of safer sedatives, lead to the disappearance of Nervine and similar products from American shelves by 1975.
Image 1 is from Retronaut.
Image 2 is from Britannica Blog
Image 3 is from Polite Dissent
Image 4 is a screen capture of Eli Lilly & Company's 1920 Handbook of pharmacy and therapeutics
Note 1: The depressant ethanol pre-dates bromides, but ethanol wasn't designed to be a sedative.
Note 2: Bromides were also commonly used to treat epilepsy and a great deal of what is known about bromide's biochemistry is due to epilepsy research.
Note 3: The action of neurons and the various parts of neurons was simplified.
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