This Is What Popular Cold Medicines Actually Do Inside Your Body

what is in cold medicine


Sooner or later, we all fall victim to a seasonal cold. And when our symptoms get rough, we often feel the need to reach beyond homeopathic remedies for the high-octane stuff. Yep, we’re talking those over-the-counter medications packed with mysterious pharmaceuticals we know next to nothing about. But if we’re going to pump our bodies with chemicals, it might not be a bad idea to learn about exactly what they’re doing once we down them. Below are some of the most commonly consumed OTC cold meds and what they actually do once they’re inside your cold-riddled body.

Tylenol Cold + Head Congestion Severe

This popular pick from Tylenol is a combination medication that aims to provide relief from multiple symptoms. It contains acetaminophen, a common pain reliever and fever reducer that’s fine in small doses but can lead to fatal liver problems if consumed chronically and in high quantities. (Don’t consume alcohol when using this medication.) It also uses guaifenesin for its expectorant properties, which is the component that helps to loosen mucus sitting in your nose, sinuses, throat and lungs and makes it easier to clear it from your system. There are a handful of common side effects that can come with taking guaifenesin, from drowsiness to stomach pain, so be aware before you pop this pill. Finally, this Tylenol product includes phenylephrine hydrochloride for its nasal decongestant benefits. It also comes with its fair share of potential side effects like dizziness and an accelerated heartbeat, so be on the lookout for an adverse reaction there, too.

Theraflu Multi-Symptom Severe Cold

This powder you pour into hot water to create a medicinal tea, so to speak, is very similar in composition to the Tylenol option above. It contains a hefty dose of acetaminophen for fever reduction and pain relief (significantly more than Tylenol, actually), so be mindful of your liver here, and it uses phenylephrine hydrochloride to help decongest your nasal passages. Its primary difference is the inclusion of dextromethorphan hydrobromide, which acts as both an antihistamine and cough suppressant in this little cocktail. It’s a standard cough medicine but does come with its list of common side effects, including blurred vision and dry mouth. Additionally, it’s worth noting that this powder contains aspartame, a synthetic sweetener, to flavor the drink. On the plus side, Theraflu includes a little potassium and sodium in its recipe, both of which are important electrolytes that your body needs as you hydrate and recover from a cold.

what is in cold medicine

Unsplash/Rex Pickar

Robitussin Cough + Chest Congestion DM

Ah, that tasty cough syrup of your childhood you miss so much! Just like Theraflu, Robitussin’s primary cough-suppressing ingredient is dextromethorphan hydrobromide, and it contains the same dose as well. It also uses guaifenesin for its mucus-clearing benefits like Tylenol, but it has twice the quantity per dose, so the likelihood that you’d experience side effects more strongly is high.

Mucinex DM

Mucinex is all about getting rid of your phlegmy symptoms after the feverish part of your cold has passed. It contains triple the amount of guaifenesin as the Tylenol pick above, so its expectorant power is top on this list. Just be aware that your side effects could be more severe because of this mega dose. It also uses the same amount of dextromethorphan hydrobromide as Theraflu and Robitussin, matching their cough suppressant benefits (and side effect potential).

Vicks NyQuil Nighttime Relief

Last but not least, we have the knockout medicine on the list. Vicks contains the same amount of acetaminophen as the Tylenol option on this list so, seriously, always be mindful of how long you’re taking cold medicines because your liver really doesn’t like them. It also has dextromethorphan hydrobromide to suppress an uncomfortable cough — just a little less than Theraflu, Robitussin and Mucinex. Then it introduces a new medicine to our list, doxylamine succinate, which is a powerful antihistamine, AKA the reason Vicks sends you to dreamland so quickly. (For a little frame of reference, Unisom SleepTabs use doxylamine succinate as the primary active ingredient to help people sleep easier at night.) Most of its side effects relate to drowsiness and dizziness, but if you reach full-on hallucinations, tell your doctor ASAP.

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