Disclaimer: None of the information in this article constitutes medical advice, and is just the opinion of the writer(s) and published for informational purposes only. We recommend that patients follow their doctor’s guidance in regard to over-the-counter (OTC) medication.
NyQuil is one of the most popular OTC cold and flu treatments. It’s sold under the Vicks brand, and comes in a variety of formulations and flavors.
Many consumers turn to Vicks for their symptom treatment because it’s available in most pharmacies and convenience stores across the U.S., but are its ingredients actually proven to work? And are there any harmful inactive ingredients?
These are the questions we’ll seek to answer in this article.
NyQuil Relief Liquid Active Ingredient Review
One of the most popular NyQuil products is their liquid formulation, called “Alcohol-Free NyQuil Cold & Flu Nighttime Relief Liquid.”
This product contains three active ingredients. The first is acetaminophen, which is a well-studied analgesic (pain relief) ingredient. This is also the main active ingredient in Tylenol, as we discussed in our recent review of how long does it take Tylenol to work.
Acetaminophen is proven to be effective for pain relief. A clinical trial compared the effects of this ingredient to a placebo for postoperative pain. The group taking acetaminophen experienced significant pain relief, with only 18.54% of this group experiencing moderate-to-severe pain.
In comparison, 56.78% of the group taking a placebo pill experienced moderate-to-severe pain.
The second active ingredient is chlorpheniramine maleate, which is an antihistamine. This class of drugs is typically used in allergy medication, because it reduces runny nose and sneezing, which are also common during a cold or flu.
Not only is this ingredient an effective symptom reliever for the reasons described above, but research shows it’s also an effective antiviral. The linked research study, published in the Frontiers in Microbiology journal, found that chlorpheniramine maleate inhibited a number of viruses, which makes it an excellent choice for this formulation.
The final active ingredient in NyQuil Relief Liquid is dextromethorphan hbr, which is used as a cough suppressant. This ingredient is proven effective for that outcome, and was actually approved by the Food and Drug Administration (FDA) in the U.S. for its use as a cough suppressant.
The FDA reviews a number of research trials on the safety and efficacy of an ingredient prior to approval, so we will conclude this is an effective choice.
NyQuil Relief Liquid is well-formulated for efficacy. All three of its active ingredients have significant research backing, and this product should reduce pain, relieve itchy and runny nose, and reduce coughing on average.
NyQuil Relief Liquid Inactive Ingredient Review
NyQuil Relief Liquid contains a number of questionable additive ingredients that we don’t believe are the best choices from a health perspective. This is common in commercial OTC products.
This product contains three separate sweetening agents: high fructose corn syrup, acesulfame potassium and saccharin sodium.
As documented in medical research, high fructose corn syrup may increase the risk of obesity. It has very low nutritional value, and is a cheap industrial byproduct used to sweeten packaged goods. We recommend avoiding it entirely in food or medicine if possible.
Acesulfame potassium is associated with both negative changes to gut function and negative changes to brain function in some research trials, as we documented in our Prime drink review (another commercial product containing this sweetener).
NyQuil Relief Liquid also contains the artificial food dye FD&C Red No. 40. A clinical trial published in 2012 found that this ingredient was contaminated with carcinogens (cancer-causing chemicals), and the researchers suggested that all artificial food dyes be removed from the food supply for safety concerns.
The final inactive ingredient we want to highlight is citric acid, which is a flavor enhancer that can be derived from citrus fruit like lemons, but is typically derived from mold. A medical review found that around 99% of the world’s production of this ingredient came from a specific type of mold and that this ingredient may cause whole-body inflammation in some cases.
We don’t believe it’s logical that a product intended to improve consumers’ health while sick contains so many questionable additives. Of course the product contains very small amounts of these inactive ingredients, and we’re not suggesting that NyQuil is likely to be harmful short-term. We just don’t believe it makes sense to take a product containing artificial sweeteners, and artificial food dye when you’re trying to get healthier, especially when there exist cold and flu products on the market without these additives.
NyQuil LiquiCaps Active Ingredient Review
Another one of NyQuil’s most popular products is their “LiquiCaps” for cold and flu, which actually have a slightly different formulation so we felt it would be valuable to review this product as well. The full product title is “NyQuil Cold & Flu Nighttime Relief LiquiCaps.”
Two of the active ingredients in this product are also in the liquid we previously reviewed (acetaminophen and dextromethorphan hbr), so we can conclude these are effective.
The unique active ingredient in this formulation is doxylamine succinate, which is an antihistamine. A clinical trial found that this drug reduced symptoms of runny nose and sneezing, so we’ll conclude that it’s an effective ingredient choice for a cold and flu product.
As with the previous product, we believe that NyQuil LiquiCaps are likely to be effective for their stated health goal of reducing symptoms of cold and flu. This isn’t surprising given that Vicks is one of the largest medicine manufacturers and has been in business for over 100 years. They have many scientists on their team that can formulate effective medications.
NyQuil LiquiCaps Inactive Ingredient Review
As with the previous product, there are a number of inactive ingredients that we disagree with from a health perspective in the LiquiCaps.
This product contains two artificial food dyes (D&C Yellow No.10 and FD&C Blue No. 1), which makes it worse in our opinion than the previous product which only contained one.
The LiquiCaps also contain titanium dioxide, which is banned in the European Union (E.U.) for use as a food additive due to toxicity concerns. The E.U. has much better consumer protection laws than the U.S. The researchers quoted in the linked press releases stated that they could not establish any safe intake level of this ingredient.
This product contains no artificial sweeteners.
We would still not recommend this product due to the inactive ingredients, but we believe it’s a healthier choice than NyQuil Relief Liquid due to the lack of sweetening agents.
We would recommend Maty’s Cough Syrup over NyQuil for a natural reduction of cold and flu symptoms. We have no commercial affiliation with this brand.
Maty’s cough syrup is sweetened with organic honey which is a much better option than artificial sweeteners. Not only does it taste good, but honey is proven in medical research to have significant antimicrobial effects. This makes it a perfect choice for a cough syrup.
This product also contains zinc, which is a mineral that can be effective short-term against infection. A medical study concluded that zinc was effective for the common cold, reducing symptoms significantly within 24 hours.
The final ingredient in Maty’s cough syrup we want to highlight is clove, which is a botanical ingredient you may recognize from your spice rack. This plant has research backing which suggests it may be effective for treating respiratory ailments and viruses.
We’re not suggesting this product is more effective than NyQuil. In regard to symptom relief alone, we believe both NyQuil products are more likely to be effective given that they contain well-studied pharmaceutical ingredients.
We just consider Maty’s Cough Syrup as a healthier option for consumers wanting to avoid the additive ingredients in NyQuil that we’ve highlighted in this review.