Can a placebo reduce the urge to cough?

The desire to cough after inhaling the spicy substance in chili peppers can be soothed by a placebo, suggesting that coughing can be controlled by more sophisticated thought centers in the brain, according to a small new study.

Stuart Mazzone, of the University of Queensland in Australia, and colleagues found that, on average, people given a placebo had 45 percent less of an urge to cough when inhaling capsaicin than they did when they did not receive placebo.

“It’s as if the brain has some occasion to control when to cough or not,” said Omer Van den Bergh, a professor at the University of Leuven in Belgium, who was not involved in this study.

Ronald Eccles, the director of the Common Cold Centre at Cardiff University in the U.K., said that the study supports earlier work that placebos work just about as well to reduce coughing as anti-cough medicines.

“I think the key point is that if patients believe in a cough treatment then it does work for them,” Eccles told Reuters Health by email.


An emerging idea among cough researchers is that coughing is not only a simple reflex, but is regulated by other areas of the brain that can be influenced by expectations that a substance can soothe the cough.

Mazzone’s group sought to understand whether a placebo could also influence the urge to cough, which is the perception of irritation in the airways that precedes coughing.

Most natural remedies for persistent cough

Remedy No. 1. Learn how to cough only through the nose (i.e., with your mouth closed all the time). It will help you to reduce irritation of airways and bronchospasm, and increase oxygen levels in body cells and the brain.

Remedy No. 2. After you have mastered Remedy No. 1 (it may take 1-2 days), learn how to cough with the mouth and nose closed. You simply need to keep the mouth closed and the nose pinched. This will further increase your body and brain oxygenation.

These 2 easiest remedies are often sufficient to stop or reduce bouts of persistent coughing and gradually to recover. However, you can subdue coughing even faster if you use the most potent anti-coughing breathing exercise called “reduced breathing”.

Remedy No. 3. Sit down in a comfortable position, preferably at an ordinary table on a straight chair. While having the bout of coughing, try your best to relax and at the end of your usual exhalation, pinch your nose and hold your breath (the mouth should be closed all the time) until you experience moderate discomfort.

If you cannot hold your breath due to severe coughing, pinch your nose and keep mouth closed while coughing without any air exchange. Why? Your goal is to increase the CO2 content in your airways so that you calm down the cough receptor-cells that become irritated due to several mechanical and biochemical factors during acute coughing bouts. These nerve cells stimulate the breathing centre in the brain both to initiate and to continue coughing.

After the breath hold, when you get a moderate or distinctive desire to take a breath, take only a small (or short) inhalation (one small sniff) and do it only through your nose. After this small inhalation, focus on relaxing all body muscles again, especially in the upper chest and shoulders in order to exhale slowly. If coughing is present, your goal is to limit your air or gas exchange to very small amounts. Ideally, the exhalation must be natural and unforced. Then take another (smaller) inhalation and again completely relax to exhale.

The researchers asked 21 people to participate in a study in which they inhaled capsaicin, a component of chili peppers that makes people cough.

After finding how much capsaicin each person needed to inhale to get the urge to cough, the researchers made the participants believe they would be getting lidocaine - a local anesthetic that make the chemical less irritating - or a placebo as treatment.

In realty, however, all participants inhaled only inert gases that wouldn’t impact their urge to cough.

After inhaling the inert gases, the participants inhaled full doses of capsaicin and asked whether they thought the “treatment” helped suppress their urge to cough.

In the first instance when the people were given the placebo, nine of them reported that they had less of an urge to cough than a group who were knowingly given a full-dose of capsaicin without any “medicine.”

How to Stop Coughing at Night
How to stop coughing even at night? Persistent coughing at night or daytime is the most common symptom among asthmatics. Over a quarter of million of asthmatics became symptom-free naturally and stopped persistent coughing at night using one breathing technique. The name of the technique is the Buteyko Emergency Procedure to stop bouts of persistent coughing naturally and fall asleep quickly.

The Buteyko breathing method has been used by more than 100 MDs in the USSR and Russia for over 40 years. These doctors taught this exercise to their patients with asthma, COPD, bronchitis, emphysema, cystic fibrosis, and other conditions. It also solves the problem how to stop coughing at night. It works fine for dry cough at night, excessive or severe cough, nagging bouts of coughing, and in other situations. Can’t stop persistent coughing during the day? Try this method too.

Coughing means breathing about 3-5 times more air than the medical norm. This activity is called “hyperventilation”. Overbreathing reduces oxygen levels in the brain, heart, and all other vital organs (see links with medical studies below). This is the main reason why coughing promotes chronic diseases, like asthma, COPD, cancer, diabetes, heart diseases, and many others.

On average, the participants had a 45 percent reduction in the urge to cough - from about a four on a 10-point scale to roughly a two.

“I was a little surprised by the magnitude of the response. It was very large,” Mazzone told Reuters Health.


Small studies have suggested that many other conditions respond to placebos, from depression to urinary problems to pain.

A recent study found that in some people, for example, depression responds well to placebo - sometimes just as much as to talk therapy or antidepressant medications (see Reuters Health report of December 21, 2011).

Mazzone said the placebo response in cough appears to be even greater than in other health conditions.

A placebo’s effect on pain, for instance, typically only reduces pain sensations by about 25 to 30 percent, compared to the 45 percent he saw in his study, Mazzone told Reuters Health.

“It’s difficult to know why that is” that cough responds so well to placebo,” he added, speculating that the cough reflex is less hard-wired than the pain reflex, because the latter is “so critical for survival.”

SOURCE: CHEST, online May 31, 2012.


The effect of placebo conditioning on capsaicin-evoked urge-to-cough

Participants reported a significant decrease in mean urge-to-cough ratings to capsaicin challenge following placebo compared to no-treatment (p

<0.001), with a peak decrease of 45 percent. The placebo inhaler alone had no effect on urge-to-cough subjective ratings when participants were aware that it contained no active medication.

Conclusions These data confirm that the urge-to-cough is susceptible to placebo inhibition. This provides further evidence that higher brain networks are involved in the processing of respiratory sensations related to airway irritation.

  Jennifer Leech,
  Stuart B. Mazzone and
  Michael J. Farrell

Provided by ArmMed Media