Various healthy natural products for immunity boosting and cold remedies on white background.
Research report
3 May 2017

Cold & flu remedies: What works and what doesn’t

We've looked at the evidence behind more than 50 products.

Member comments

Get access to comment

Francois D.
16 Aug 2019
How about Zinc Lozenges?

I saw mush news and research about the effectiveness of zinc lozenges while living in the US. It seems that these somehow limit the virus' ability to multiply - thereby shortening the cold. I was very surprised to see that these products are not on the shelves at pharmacies - curious why not, as in my experience they really seemed to work.

Consumer staff
19 Aug 2019
Re: How about Zinc Lozenges?

Hi Francois,

Thanks for the question. While some studies found zinc could have promise, unfortunately, there isn’t a reliable answer on this one - yet. The Cochrane Collaboration, which systemically reviews all the available medical research, is currently analysing the evidence for zinc’s effect on the common cold. We’re keeping an eye on this review and hope to include the results once they’re available. Sorry not to be more help!


Olivia - Consumer NZ writer

Sarah L.
13 Jun 2017
Vicks inhalers

Hi great article thank you just wondering about the benefits of the vicks chest rubs and Inhaler sticks? We're they not included in any tests? Thanks. Sarah

Previous member
13 Jun 2017
Re: Vicks inhalers

Hi Sarah,

We primarily looked at cold and flu medications, those with approved drugs that are absorbed by the body for symptom relief. Therefore, we didn’t look at inhalants, and the Cochrane Collaboration hasn’t reviewed the subject. However, there are a few studies out there (such as this one: that have found cold sufferers using the chest rubs feel their nose has cleared and/or can sleep better.

One interesting study (that has been subject to some debate) is this one: It found that the feeling of relief from inhaling the vapours may just be a subjective experience — in reality the rub may make your body produce more mucus. However, it’s important not to read too much into one study. A key thing to remember is that (unlike the inhaler sticks designed for the nose) Vicks advises you to only use the rub on your chest and throat, not under your nose. I hope that’s helped!

Kind regards,
Olivia – Consumer NZ staff member

Christina R.
22 May 2017
Any addictive cough medicine ingredients?

I have read about people overseas becoming addicted to cough medicines. Are any sold in NZ that contain addictive ingredients?

Previous member
22 May 2017
Re: Any addictive cough medicine ingredients?

Hi Christina,

It’s possible that the substance you read about was codeine, which can be addictive. Codeine is added to some cold and flu products in New Zealand, typically the pills you buy over the counter. However, Medsafe is currently considering whether to put further restrictions on the sale of codeine. Overseas, the cough medication dextromethorphan (which you’ll find in dry cough syrups in NZ) has been known to be abused, but scientists aren’t yet sure if it is a physically addictive substance.

Kind regards,
Olivia - Consumer NZ staff

Jan M.
17 May 2017
great article

thanks for this - a great article and really good to have confirmation about effective remedies.

Lewis B.
15 May 2017

Ginger has also been used to treat the common cold in China for thousands of years. No studies on this?

Previous member
18 May 2017
Re: Ginger

Hi Lewis,

Thanks for your question. The gold-standard clinical trials we’ve seen for ginger as a natural remedy tend to focus on nausea. Ginger didn’t really pop up in our research on the common cold, except being mentioned as a Chinese remedy. The Cochrane Collaboration hasn’t looked into this area, as they have for Echinacea and garlic for the common cold, for example. It may be an area that researchers haven’t thought to invest the money for a robust trial yet.

Olivia - Consumer NZ staff

Previous member
14 May 2017
UK Research

After searching for a cure for the common cold for many years the Cold Research Centre based at Salisbury in England was only able to come up with the suggestion that taking extra vitamin C and zinc might shorten the duration of the cold.

Alan F.
14 May 2017
Good Article

Couldn't agree more with the article findings, phenylephrine is useless, a complete waste of money.
I head straight to the doc for a prescription of sudomyl.

13 May 2017
I agree with this article

Octrivin is brilliant. I just use the junior one... does the job well. And in only one nostril...(too much information??) ... I find extends how long I can use it.

Previous member
13 May 2017

A friend of mine, who is a retired doctor told me a few years ago that zinc is the only thing with proven impact. Did you look at this?

David H.
13 May 2017
+1 for Zinc

I'm pretty sceptical about most supplements but zinc really does seem to lessen the length and severity of any colds I catch. The virus always used to end up in my lungs, much to the 'delight' of those who had to put up with my coughing, but ever since taking zinc at the first sign of a cold, it hasn't been a problem. I still get the cold but it never lasts as long as it used to. New Scientist also ran a comparative article ( which said there was some evidence for the efficacy of zinc supplements.

Previous member
15 May 2017
Re: Zinc?

Hi Lesley,

There has been a bit of uncertainty over the science on zinc for the common cold. We rely on the experts at the Cochrane Collaboration and their assessment of the scientific trials of natural remedies. A few years ago, Cochrane released a review of the research for zinc and did conclude the mineral was effective at helping people fight off a cold.

However, last year (after a number of errors in the review were pointed out) Cochrane withdrew this review. Because of this complex situation, we decided not to comment on zinc in the article, but will update it the next time Cochrane re-reviews the trials. We didn’t want to guess for ourselves what this withdrawal meant (you can read more here: It may be that the next review comes to an entirely different conclusion or that it simply finds that zinc is effective, but the experts aren’t as confident in that conclusion as they were previously. I hope that has helped to answer your question.

Olivia - Consumer NZ staff

Steven P.
08 May 2017
Pseudoephedrine was a very effective decongestant - lets have it back again

Whilst the P drug is a serious problem, surely pseudoephedrine can be made into a tablet that remains effective yet is extremely difficult to extract and make P from?

Then we could go back to having an effective cold symptom reliever. I used to simply take paracetamol and sudomyl 60mg tablets. When a cold was heavy I could 3 tablets a day (morning/lunch/night) and as you "dried up" and the cold became less you could drop that 2 tablets morning/night and then 1 tablet at night and finally none.

You could buy 60 x sudomyl tablets for ~$10 and it was HIGHLY effective.

The modern cold remedies are just rubbish. This consumer article reinforces for me what I already believed.

I hope there is a way that pseudoephedrine can be delivered that will make it very difficult to extract. The first drug company that can come up with a good format will make a fortune - an effective cold symptom reliever back on the market.

You can still get sudomyl 60mg tablets from the doctor, but, you get the Spanish inquisition and they will only supply very small quantities (10 tablets) at a time.

The few have wrecked it for the many!

13 May 2017
best way to prevent extraction

Agreed. Looking at P usage worldwide, it's problematic in deprived communities. In order to have effective cold medications again, voters need to seek policy that reduces social inequity

Jo R.
26 Aug 2020
Discontinued too

The alternative Sudomyl you mention has now been discontinued too. So far the only working alternative found is kiwi made Rocket Fuel by SavvyTouch. Does not fix sinus like sudomyl but it helps to relieve, which is more that a lot do and it its natural

H W.
04 May 2017
Kaloba works..medically proven

You missed Kaloba. Clinically tested in medical is a natural antiviral with proven efficacy and now registered as a medicine in some countries. Safe for kids. My family have used it for years

Previous member
08 May 2017
Re: Kaloba works..medically proven

Hi there,

Thanks for your comment. The 50 products we looked at were based off common cold & flu ingredients sold in supermarkets and pharmacies (the ones consumers were most likely to buy) and Kaloba didn’t pop up.

While Cochrane have looked at it, most of the scientific evidence it examined concerned chest and sinus infections, rather than the common cold:

Olivia – Consumer NZ staff

Andrew Crosby
04 May 2017
Spoilt by idiots

10 years ago we had an effective decongestant​, sadly some idiots decided it was just the thing to get high on, could we try to get it back some how? A national purchase register sounds to me like a great idea...

Paul W
07 May 2017
May as well take sugar pills

I agree. Now days you pay about $18 for what basically amounts to sugar pills. No use whats so ever. Thanx to the current Government on banning the stuff that worked

04 May 2017
Fair Trading Act?

Have you referred your findings to MBIE? Isn't this similar to the Nurofen claims?

Previous member
04 May 2017
Re: Fair Trading Act?

Hi Simon,

While the Fair Trading Act protects consumers from misleading claims, there’s also protections in the Medicines Act specifically prohibiting misleading claims on medicines. Because of this, we think Medsafe, who is responsible for enforcing this legislation, is the appropriate agency to investigate. We’re keen to see how they respond to the request we’ve made for them to review both the marketing and benefit-risk ratio of these products.

Olivia - Consumer NZ staff