Once upon a time, before the end of the last century, Americans could buy cough medicines that worked. Codeine-containing syrups were widely available without prescription. Physicians also recommended terpin hydrate, an expectorant, from the late 1800s until the early 1990s.
Codeine is now much harder to find over the counter, although some states allow people to buy low-dose cough syrups. The purchase requires the extra security step of signing for the syrup, presumably to discourage abuse.
Terpin hydrate was removed from the market because the FDA had not received enough data to support its effectiveness. (A high-ranking FDA official admitted to us off the record that he had personally used it and found it helpful.)
As a result, we entered the 21st century with dextromethorphan as the primary ingredient in OTC cough remedies. It is the DM in Robitussin DM and other popular brands.
Now, though, the effectiveness of dextromethorphan is being questioned. The American College of Chest Physicians has issued new guidelines on the diagnosis and management of cough.
According to Richard Irwin, M.D., the head of the committee, “There is no clinical evidence that over-the-counter cough expectorants or suppressants actually relieve cough.��?
This shouldn’t come as a big surprise. In 2004, a study showed that neither dextromethorphan nor diphenhydramine (the antihistamine in Benadryl) worked better than placebo for kids’ coughs (Pediatrics, July 2004). Ian Paul, M.D., assistant professor of pediatrics at Penn State Hershey Medical Center, headed the study up. He told us, “One of the conclusions you could come to from the results of our study is that these medicines don’t work [for kids].��?
What makes DM more troubling is its potential for abuse. Some teenagers take high doses and may experience irregular heart rhythms, high blood pressure, confusion, hallucinations or seizures.
What can you do for a stubborn cough, then? If it is just a temporary symptom due to a cold, doctors mostly recommend “tincture of time.��? In other words, it will go away on its own.
That’s not entirely satisfying if someone in the household is hacking away and keeping the whole family awake. We’d like to suggest a different tincture of thyme—a nice warm cup of thyme tea, made with a half-teaspoon of thyme leaves per cup of water. A tea made from grated fresh ginger root can also be helpful. Either may be sweetened to taste, and both contain compounds that help suppress cough.
Another approach is to apply Vicks VapoRub to the soles of the feet. Socks will protect the sheets. We can’t explain how it works, but many readers vouch for it as a nighttime cough suppressant.
If your doctor will prescribe a codeine-containing cough medicine (Cheracol Cough syrup, Guiatuss AC syrup, Romilar AC liquid or Tussi-Organidin NR), you’ll get relief from a hard-to-control cough and it may help you fall asleep.
Another surprising option might be dark chocolate. Scientists at the National Heart and Lung Institute in London have found that theobromine, a compound in chocolate, is more effective than codeine for suppressing a cough. Someday it may show up in a good-tasting, effective cough medicine.

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