The common cold causes a sore throat, headache, sneezing, a runny nose or nasal congestion,
and coughing which usually starts a few days after the other symptoms, but often develops
into the worst symptom and can linger for a few weeks.
Bronchitis causes chest congestion, shortness of breath, wheezing, and once again, a lingering
Both are viral infections so antibiotics don’t work, but the symptoms can be rough, so, what’s
the best medication for treating a cough due to the cold or bronchitis?
Unfortunately, many over-the-counter cough remedies haven’t been recently tested and
when they have been, many are found to be ineffective.
Also, simply taking something for a cough can make a person feel better, so there’s
also a placebo effect at work.
In general, there are three ways to study how well a cough medication works.
The first way is a survey that simply asks people if a medication helped them recover
from their cough.
The second way is called the challenge method because healthy people are challenged with
citric acid or capsaicin—the molecules that make hot peppers hot—both of which can induce
Then the medication is given to see if it reduces the coughing.
The third way, cough counting, involves a person with a cough wearing a recording device
that counts the number of coughs they have before and after they take a medication.
This last way is considered the best (yes, really) by regulatory agencies like the Food
and Drug Administration, but the results don’t always correlate with results from surveys
and challenge studies.
So, with this in mind, a recent review in the British Medical Journal took a look at
the effect of various over-the-counter cough medications by looking at all three types
Now, the availability for each medication varies by country.
For example, codeine is only available with a prescription and Levodropropizine is not
readily available in the United States.
That said, codeine doesn’t appear to stop coughing by any method of measurement, and
while Levodropropizine appears to decrease coughing in subjective and challenge tests,
those results aren’t supported by cough counting studies.
Another interesting medication is menthol, which is thought to reduce cough by being
a mild anesthetic.
It’s included in a lot of different cough relief formulation, and works in cough challenge
tests, but not in subjective or cough count tests.
In fact, of everything studied there was only one medication that was effective in studies
using cough counting, cough challenges, and surveys: that medication is Dextromethorphan.
Dextromethorphan is believed to help stop the cough reflex in the brain.
It is a widely sold anti-cough medication and is found in formulations like Vicks DayQuil
Cough and Robitussin.
While dextromethorphan has been shown to work better than placebo in a number of adult studies
there are a lack of large studies in children, so it is not clear if this this medication
works for them.
That said, it is included in a number of formulations designed for children.
As for recommendations to decrease a cough due to the cold or bronchitis the BMJ review
suggested this strategy.
First, take agents that are designed to soothe the throat like cough drops or adding honey
This can help with temporary cough relief, and is a relatively safe place to start.
Next for isolated coughs, a daily dose of 30-60 mg of dextromethorphan is recommended
Finally, coughing due to colds or bronchitis usually resolves in a few weeks, so if it
doesn’t get better it’s important to seek out a healthcare professional.