The FDA warned consumers not to use zinc-based cold remedies in 2009.

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Until 2000 or so, most cold remedies contained phenylpropanolamine as the decongestant.

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The nasal drainage associated with colds can hasten dehydration, and some over-the-counter cold remedies containing antihistamines (many cough syrups, for instance) can dry you out further, Dr. Rosenbaum points out.

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Some cold and cough remedies include banned stimulants such as ephedrin and pseudo-ephedrin.

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In Mrs Beeton's Book of Home Management, a best-seller for decades after it was first published in 1861, there is a chapter on first aid and home remedies - including a hot toddy cold treatment.

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Add in the various over-the-counter remedies for flatulence, constipation, diarrhoea, hay fever and the common cold, and the average American might seem to be a pill-popping hypochondriac.

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