A sweet remedy that’s worth coughing up for?

Experts says we need to get rid of the myth there are different kinds of cough

FOR such a common problem, treating a cough appears to be incredibly complicated. There are dry coughs and wet ones, tickly coughs and chesty ones and dozens of different elixirs and syrups designed to relieve all of them at different times of the day.

 

A recent survey confirmed seven out of 10 of us who buy cough medicines will choose remedies for a specific type of cough – and almost a third of us who use them have at least three different products in our medicine cabinets.

But cough expert Professor Alyn Morice says we are wasting our money. “We need to get rid of this ridiculous idea of different types of cough. It’s a myth.”

It goes back to the times of myth and legend. The ancient Greeks believed all illness stemmed from an imbalance of four humours: black bile, yellow bile, phlegm and blood.

Bile soon took a back seat but bloodletting was a commonplace medical procedure up to the late 1800s and the prevalence of TB, which produces large quantities of mucus, meant phlegm was still considered important well into the 1900s.

 

However Professor Morice, who is head of cardiovascular and respiratory studies at the University of Hull and York Medical School, says although science has moved on, treatments for common coughs have not and most are still shaped by this approach.

“From a marketing point of view it’s a sound strategy,” he says. "But from a scientific view it is outdated. There is absolutely no doubt scientifically that it is hypersensitivity of the upper respiratory nerves that creates the urge to cough.”

Most common coughs are triggered by viral infections such as colds and flu. Adults can expect to catch between two and four colds a year, while children can get eight or more.

Coughs usually develop within 48 hours of cold symptoms. Our cough reflex is designed to clear any obstruction from the airways, but Professor Morice says: “The virus hijacks this defence mechanism and deliberately makes nerves in the upper respiratory tract hypersensitive in order to spread itself around.

“Common coughs may present with different symptoms but they are all driven by the same underlying mechanism – this heightened cough reflex sensitivity.”

 

Almost a third of us have at least three different products for coughs in our medicine cabinets

 

Honey and lemon are more effective than a placebo and a number of ingredients of OTC cough medicines

There is no good evidence for or against the effectiveness of OTC medicines in acute cough

Professor Alyn Morice, University of Hull and York Medical School

 

So what is the best way to get a cough under control? A Cochrane review of over-thecounter (OTC) cough medicines, which analysed the results of 29 trials involving 4,835 people, found: “There is no good evidence for or against the effectiveness of OTC medicines in acute cough.”

However, the authors did add that more research was needed because flaws and weaknesses in many of the studies meant the results of this review “have to be interpreted with caution”.

Professor Morice argues there is clear evidence syrups such as honey and lemon are more effective than a placebo and a number of ingredients of OTC cough medicines, such as antihistamines, expectorants and cough-relieving diphenhydramine have also been shown to relieve symptoms – although he believes it is purely because they also help damp down cough reflex hypersensitivity.

And now a study co-ordinated by scientists at King’s College London has confirmed that Unicough, the first new cough medicine to be licensed in 30 years, is clinically proven to reduce the frequency of coughing and reduce sleep disruption due to a cough.

The ROCOCO study, the largest real-world study of an OTC cough medicine in Europe, involved 163 patients recruited from 18 pharmacies and five GP practices and compared Unicough to a standard linctus.

 

It found that Unicough “significantly” reduced cough frequency and sleep disruption after two days of treatment and twice as many patients taking it stopped treatment early because their cough had cleared up.

The medicine, which can only be bought in pharmacies, contains diphenhydramine and ammonium chloride, ingredients used in a number of different cough medicines that have been proven to relieve symptoms, as well as levomenthol, a decongestant with a mild anaesthetic and cooling effect.

But it also has a touch of Mary Poppins-style magic, because a spoonful of chocolate not only makes this new medicine go down, it also plays a major role in soothing the jangled nerves which trigger coughs.

Cocoa is known to contain a compound called theobromine which helps to suppress coughs and perhaps more importantly, it makes it stickier and more viscose than standard cough medicines and this acts as what doctors call a “demulcent” and forms a soothing coating which calms and protects sensitised nerve endings.

However Professor Morice says there may be other benefits. “We don’t understand all the receptors involved in a mechanism like a cough but I am absolutely convinced there is a chocolate receptor and the cocoa is going to have some additional effect.”