Unicough: Sadly not as good as unicorns.

Another day and another new cough medicine has mysteriously appeared on pharmacy shelves.  It’s called Unicough® (Infirst), and it claims to work by:

addressing the hypersensitivity of the cough reflex, which makes it suitable for dry, tickly and chesty coughs
— http://www.chemistanddruggist.co.uk/news/new-cough-syrup-pharmacy-only#sthash.toAK6A2l.dpuf (subscription required)
source: http://www.infirst.co.uk/were-working-on/unicough

source: http://www.infirst.co.uk/were-working-on/unicough

Riiiight. Regular readers will by now know that most cough medicines are absolute nonsense, with little to no evidence of effectiveness. I’m particularly suspicious of products (like this one and Bronchostop, for example), which claim to be able to work on any type of cough. Chesty and dry coughs happen through different mechanisms, so a product that claims to treat all types seems more likely to not work for any. An exception to this would be a simple demulcent like simple linctus, which acts just by coating the throat for a little while. 

Am I right to be suspicious about this product? Well dear friends, lets take a deep, objective breath and dive into the evidence, hoping beyond hope that maybe this time… this time… it might not be a nonsense product. 

Is it actually a medicine? Or is it just pretending? 

Unlike most new over the counter products which all turn out to be medical devices masquerading as real medicines, this product is actually, genuinely a Real Life Medicine. It even has a Real Life License, for the symptomatic relief of common coughs associated with upper respiratory tract congestion. What larks! What a time to be alive!

This means that the manufacturer will have proven three broad things in order to receive the license: safety, efficacy, and quality. We’re not out of the woods yet, by any means, but this is probably the most promising start to an OTC medicines review I’ve done so far.

It contains diphenhydramine 14 mg (an antihistamine, which as a side effect will make you sleepy), ammonium chloride 135 mg (irritates the airways, therefore is supposed to loosen up any mucus and help you cough it up- aka an expectorant), and levomenthol 1.1mg (minty, therefore feels a bit soothing and cooling). Despite Infirst’s hopes that Unicough will “reshape the approach to acute common coughs”, there are no exciting or revolutionary technologies here. All of these drugs are old as the hills, and very similar products (Benylin Chesty Cough Original) have been widely available for pretty much forever.  

Furthermore, it is a totally irrational combination of drugs. You’ve got an antihistamine, which acts to dry up secretions, nestling up alongside an expectorant, which is supposed to promote loosening up secretions. Those two actions work against each other and cancel each other out, rendering the whole thing pretty darn pointless. 

If it's licensed, that means that there is evidence that it works though, right?

Ummm… no. It seems that it’s managed to get its license on the basis of being exactly the same (save for flavouring) as another product called Histalix®. That product got its license in 1999, seemingly on the basis of thin air. It’s safe to say that back then licensing for OTC products was rather less rigorous than these days, and “but it’s been around for a while now” used to be a legitimate reason to grant a license. Now, I can’t find the information that the manufacturers of Histalix® presented at the time, but I’m guessing it’s probably not a whole suite of robust, well designed trials.

An article about the product in Chemist+Druggist magazine gave some vague details about a trial:

A randomised study of 163 patients co-ordinated by King’s College Hospital, London, found that the cocoa-based formulation was more effective at reducing the frequency of coughs and the disrupted sleep caused by coughs than simple linctus, Infirst Healthcare said
— http://www.chemistanddruggist.co.uk/news/new-cough-syrup-pharmacy-only#sthash.toAK6A2l.dpuf

This trial, however, doesn’t appear to be published anywhere. I contacted the manufacturers asking for more information about it and was, perhaps predictably, met with silence. Without knowing how the trial was designed, and what the results were, we will have to just discount it; it’s the medical equivalent of being told that no, this Rolex watch someone wants to sell you for £20 is definitely not a fake, honest guvnor. It’s worth noting too that the comparator they used, simple linctus, is no better than placebo itself. 

Searches of the medical literature found a great deal of nothing, either. I searched for both Unicough® and Histalix® too, as well as the combination of ingredients, to no avail. Yes, it might help you get to sleep at night thanks to the antihistamine side effects, but I wish they would be honest about that in their marketing. You’ll sleep because you’ve been knocked out by drugs, not because its made any difference to your cough. 

Is it safe? 

On the whole, there probably aren't any major safety concerns here. Drowsiness is going to be the main problem with it, and as with all things that can cause drowsiness there is a possibility of dependence. Other effects could be dry mouth and urinary retention. It can interact with a few different medicines. Of course there is always the potential issue of self-treatment of a persistent cough, and masking of symptoms that could suggest a more malignant cause. 

The practicalities

Any product which causes drowsiness is going to be severely limited in its usefulness through the day. If you drive, work, or even just don’t want to be asleep all day, then you’re going to have to avoid this product, or you might even end up having to buy two lots of pointless medicines; one for day and this one for night. Additionally, antihistamine-induced sleep can often leave you feeling still quite drowsy the next morning, and some people can even feel quite hungover. It’s not going to be ideal if you have to be up early for work, or if you drive early in the morning.

The unique selling point of this product is the taste. It's cocoa-based, which I'm sure is pleasant, but it aint going to make a blind bit of difference to your cough. I even wonder whether a pleasant taste might have a detrimental effect on any placebo effect: if it doesn't taste like medicine, then you might get less of a response. 

Is the cost reasonable?

Whoah, £8.85 for 150 mL? Give over! There is absolutely, categorically no way that this product is worth that amount. 

TL:DR! Is it worth a punt? 

Nope. There’s no evidence it works, and the combination of ingredients in it makes no sense. Save your money and invest in some cheap simple linctus or glycerine, honey and lemon to soothe your throat instead. The best cure for a post-infective cough is time. Look after yourself, rest, drink plenty, and eat well. If your cough doesn’t go away after about three weeks, get yourself checked over. I know that coughs can be awful, annoying, embarrassing, and exhausting, but –and I’m sorry to have to tell you this- nothing will get rid of it instantaneously, or even any quicker than using nothing at all, so you might as well save your pennies. 

A Mahoosive Thank You

Last month, in a drunken moment of possible madness, I decided to set up a Patreon page. I did so hoping that even setting the page up might work as a driver to overcome the writer's block that has been cursing me for too long. I set the target amount as a dollar, and limited paid posts to these OTC product reviews, because I think there is a real gap in the market for them, and ultimately they will hopefully help people save money. 

To my utter astonishment, four kindly patrons stepped up and made pledges. I doff my cap to you and can't thank you enough. 

Shaun Sellars
Alex Brown
Jack Wright
Bevin Flynn

If you enjoy these sorts of posts, find them useful, and have more money than sense, then I'll just leave this here

Literature Search terms:

Embase: unicough (freetext, ti.ab) Histalix (freetext, ti.ab) *Diphenhydramine AND *Menthol AND *Ammonium chloride

References: http://www.infirst.co.uk/were-working-on/unicough https://www.medicines.org.uk/emc/medicine/31365 https://www.medicines.org.uk/emc/medicine/11171 http://www.mhra.gov.uk/home/groups/par/documents/websiteresources/con553668.pdf http://www.mhra.gov.uk/home/groups/spcpil/documents/spcpil/con1445576593772.pdf