What Happens To Your Body When You Take Cough Medicine Every Day

A minor cold usually doesn't require a trip to the doctor (pandemic conditions being a notable exception). Common cold symptoms such as headache, sore throat, and coughing tend to be at least fairly well tolerated by most. Besides, plenty of medications available over the counter (OTC) are effective at addressing common cold symptoms such as nasal congestion, sore throat, and coughing. Some are even effective at addressing more than one at a time. Perhaps surprisingly, that includes OTC cough medicine, which, you may not have realized, can soothe throat irritation by reducing coughing — as well as vice versa, per Duke Health. 

On the other hand, any of these home remedies for sore throat could work that same sore throat magic — while also having the advantage of not posing the drawbacks that go along with taking cough medicine. The first is that taking cough medicine requires having it in the house, which may not be a good idea if you have children or teens living with you. It may also be inadvisable to keep cough medicine around if you or someone else in your household has issues with addiction. You see, the second drawback is that cough medicine can potentially become addictive, especially among young people, according to SingleCare. And a daily cough medicine habit will not do your body any favors. But before we get into that, there's the threshold question of whether, given that risk, you should even take cough medicine in the first place.

One hundred years ago, if you had a cough, you could have found scientifically proven relief in the form of "Heroin," via Yale School of Medicine. Manufactured by Bayer, Heroin contained diacetylmorphine — a derivative of morphine, which, being an opiate, depresses the nervous system, including the brain's "coughing center," per ScienceDirect. Effective as it was, chemical dependency became a problem. In 1924, FDA approval was rescinded.

Codeine stepped in as the cough-suppressing opioid of choice — until scientists figured out how to synthesize dextromethorphan (DXM), a cough suppressing agent that is "chemically related to" opioids without actually being an opioid, according to the U.S. Department of Justice. Over the decades, DXM came to be the most widely used medicinal cough suppressing agent in the U.S. Nevertheless, its effectiveness is frequently debated by experts (via WebMD). Moreover, some question the wisdom of ever suppressing a cough, given that coughing is one of the body's defenses against congestion and infection. 

If upon weighing the potential benefits versus risks, you decide to take cough medicine, the Mayo Clinic recommends following the label directions to a T, including not taking more than is directed, and not taking it for any longer than the label recommends. Cough medicine should never be given to children under the age of two, according to Poison. Cough medicine may also not be safe for people with certain conditions. Nor for people taking certain medications, urges WebMD.

Cough medicines tend to be marketed either as suppressants or expectorants (which loosen respiratory secretions, making it easier to cough them up), according to Dr. Kimberly Brown, Memphis, Tennessee emergency medical doctor (via Single Care). Some are both, per WebMD. Suppressants often have DXM as their active ingredient, whereas expectorants often have guaifenesin (via SingleCare). When taken as directed, both are considered safe but are associated with common side effects. The ones that overlap among the two drugs include dizziness, drowsiness, nausea, vomiting, and stomach pain, according to MedlinePlus and RXList. 

In addition, even when taken according to directions, DXM may cause lightheadedness, nervousness, and restlessness, while guaifenesin may cause headache, rash, and decreased uric acid levels. Having a decreased uric acid level is not, in and of itself, problematic (via SelfDecode Labs). However, because it can be a symptom of several serious conditions, including multiple sclerosis, Huntington's, Parkinson's, and Alzheimer's, it could complicate the results of a urinalysis, whether routine or diagnostic. 

Generally speaking, most of these side effects don't generally rise to the level of serious medical concern. A bigger issue presents if and when cough medicine use becomes a daily thing. Side effects that seem mild on a one-off basis can have a more disruptive effect when experienced daily. Moreover, both DXM and guaifenesin come with the risk of overdose, increased tolerance, and physical dependence (per Single Care). Daily use increases that risk, per FH Rehab.

Not everyone experiences side effects when taking cough medicine. Moreover, some who experience side effects may nevertheless continue to take it, particularly because taking cough medicine has come to be associated with producing a "high," according to SingleCare. The fact is that when taken at dosages higher than recommended by a doctor, pharmacist, or by the label, cough medicines that have DXM as an active ingredient can produce feelings of euphoria, which are commonly associated with being "high," according to Medical News Today. And taking DXM-containing cough medicine in higher-than-recommended doses can lead to overdose. 

Fortunately, deaths directly from DXM overdose are rare, according to the U.S. Department of Justice. However, occasional abuse of DXM has been known to escalate into regular abuse of DXM, and regular abuse of DXM can lead to physical dependence and related addiction, according to a 2013 publication in the University at Buffalo's Clinical and Research Institute on Addictions. In such case, withdrawal symptoms may present upon discontinuing use. These could include restlessness, insomnia, body aches, and gastrointestinal distress (per Withdrawal).

Because taking too much guaifenesin is unlikely to cause toxicity, per New Zealand Consumer Medicine Information, and because guaifenesin is not associated with a significant risk of addiction, according to Memphis, Tennessee emergency medical doctor, Kimberly Brown (via SingleCare), the above doesn't apply to expectorant cough medicines that contain no DXM.

Taking cough medicine that contains DXM — the most common ingredient in cough medicines sold as cough suppressants — can lead not only to physical dependence and related addiction, but also to the phenomenon known as "escalating tolerance," according to a 2013 publication in the University at Buffalo's Clinical and Research Institute on Addictions. The term "escalating tolerance" in connection with any substance refers to a gradual lack of sensitivity to the substance, as a result of which the dosage must be increased of the desired effects are to be achieved, according to a 2007 review published in the journal Pharmacology. 

While death occurring directly from DXM overdose is rare, escalation in DXM dosage is associated with a number of serious side effects, including confusion, paranoia, agitation, inappropriate affect, hot flashes, high blood pressure, and involuntary eye movement, according to the U.S. Drug Enforcement Agency (per Medical News Today). 

At higher doses, DXM can cause seizures, increased heart rate, difficulty breathing, and kidney failure. The risk of death from DXM overdose increases when mixed with alcohol — a dangerous practice that has become increasingly common among teens, according to American Addiction Centers (AAC). Lifestyle changes that may signal DXM abuse, also according to AAC, include changes in eating and sleeping habits, loss of interest in things that once mattered to an individual, including hobbies, friendships, and hygiene. 

According to American Addiction Centers (AAC), most people who abuse DXM-containing cough medicines are teenagers. The reason is that these medicines are known to produce a high, especially when mixed with alcohol; plus, they're cheap and easy to obtain, which can make daily cough medicine use seem sustainable to a teen, at least at the outset before tolerance escalates and symptoms of abuse become outwardly evident. If dosage escalates in parallel with tolerance, however, then feelings of euphoria can give way to more serious and worrisome psychotropic effects, according to Pharmacy Times. These include "delusions, hallucinations, and paranoia," according to the authors of a 2017 case study published in the Psychopharmacology Bulletin. 

"DXM, which is safe and effective as a cough suppressant and expectorant when used at recommended doses (typically 15 to 30 milligrams), can lead to serious side effects when abused," according to the National Institute on Drug Abuse (NIDA). At doses of 200 to 1500 milligrams, DXM has been known to produce psychotropic effects similar to those produced by dissociative drugs such as PCP and ketamine. Dissociative drugs don't cause hallucinations, per se, but rather distorted perceptions of sight and sound and feelings of detachment from both one's surroundings and oneself, according to the NYC Health Department. In addition, a 2006 case study published in the journal, Addiction Biology, suggests that the adverse psychotropic effects of DXM abuse may rise to the level of psychosis.

Since daily use of DXM-containing cough medicine may be associated with serious psychotropic effects such as hallucinations, delusions, paranoia, and even psychosis, per NIDA, and a 2006 case study published in Addiction Biology, the question arises whether such use may also be associated with damage to the brain. Experts seem to be somewhat divided. 

Research on rats suggests that chronic exposure to DXM during adolescence can cause cognitive impairment, including memory issues, per AAC. On the other hand, rats may respond differently to DXM than humans. Accordingly, in the absence of a randomized controlled scientific study addressing the relationship between DXM use and brain damage in humans, it can't be said that those who take cough medicine daily are increasing their risk of such damage. Moreover, a 2007 study published in NeuroToxicology specifically found that DXM use in rats — even at high levels — does not cause long-term damage to brain cells and tissue. 

While acknowledging that DXM abuse has not been proven to cause brain damage in humans, Maryland House Detox does point out other dissociative drugs such as PCP have been associated with neurotoxicity (i.e., brain damage). In any case, a 2016 study published in Drug and Alcohol Dependence indicates that at high dosages (in excess of 10-30 times the recommended therapeutic dose), DXM can produce immediate "impairments in attention, working memory, episodic memory, and metacognition."

If your cough medicine of choice is a guaifenesin-based expectorant, then you (probably) have nothing to be concerned about as far as drug interactions go, according to the Prescriber's Digital Reference, although only your own healthcare provider can really offer that level of assurance. If you're taking a DXM-based cough suppressant, however, your risk of a drug interaction is markedly higher. According to Drugs.com, at least 320 medications may interact with cough medicines containing DXM. Of these, 72 are characterized as major risks, 246 as moderate, and two as minor. Moreover, if you're taking cough medicine every day, then every single day presents another opportunity for a drug interaction.

Drugs that pose what Drugs.com calls a "major" risk when taken with DXM include the anti-depressants, Cymbalta and Lexapro, as well as the anti-nausea drug, Zofran (via the Mayo Clinic). When taken with DXM, all of these may lead to the development a condition known as "serotonin syndrome." Serotonin syndrome refers to excessive serotonin in the body, which can cause symptoms ranging from shivering and stomach upset to muscle rigidity, seizures, and even death if left untreated. 

The stimulant, Adderall may also cause serotonin syndrome. "At higher doses, Adderall can produce euphoric effects and release high levels of serotonin into the system. When they are abused, drugs that affect serotonin levels put people at risk of experiencing dangerous side effects" (via The Recovery Village). Other drugs that pose a moderate risk of interaction with DXM include Xanax and Benadryl. Symptoms include dizziness, drowsiness, and difficulty concentrating. Here's how to quell coughing without cough syrup.

Another risk of taking cough medicine every day arises if your particular cough medicine happens to contain active ingredients in addition to DXM and guaifenesin. According to The Recovery Village, "many over-the-counter (OTC) cough syrup formulations include other active ingredients that can have profoundly negative health consequences when misused." Some may be life-threatening. One example is acetaminophen, which is the active ingredient in Tylenol. Acetaminophen is sometimes included in cough medicine formulations, particularly when marketed as multi-symptom cold medications. It's best to check for the presence of acetaminophen on the label of any cough medicine you're thinking of taking, certainly before taking it every day. Chronic acetaminophen use can cause liver failure, according to the Mayo Clinic — so too can one excessively large dose.

Another active ingredient that may be found in multi-symptom cold formulations is the decongestant, phenylephrine, which is the active ingredient in Sudafed. Per WebMD, phenylephrine is meant only for temporary use. Accordingly, if phenylephrine is included as part of whatever cough medicine you may be taking regularly, then you're putting yourself at risk. The risk increases as escalating tolerance may lead to taking higher dosages. Symptoms of phenylephrine overdose can include dizziness, nausea, impaired breathing, increased heart rate, and even hallucinations and seizures. Chronic use of phenylephrine may also cause high blood pressure (via Pharmacy Times). These same risks would appear to apply to formulations containing pseudoephedrine and other decongestants.

If your cough medicine comes in the form of multi-symptom cold relief, there's a decent chance it also contains a decongestant. According to Pharmacy Times, decongestants can cause blood pressure to increase. The way this works is that decongestants temporarily narrow the blood vessels, according to the Mayo Clinic. While this may provide relief vis a vis swollen nasal membranes, it can also impair optimal blood circulation throughout the body — not unlike the way plaque buildup in the arteries can do so. In either case, blood pressure may increase. 

Fortunately, in the case of taking a decongestant, the issue tends to be self-limiting — i.e., as soon as you stop taking the decongestant, your blood pressure should return to normal. However, if you're taking cough medicine daily, and it's part of a formulation that contains a decongestant, then you may be experiencing high blood pressure on a daily basis. High blood pressure forces the heart to work harder to circulate blood. Over time, this can damage the heart and increase the risk of heart attack and heart failure (via the Mayo Clinic). It also can increase the risk of stroke, as well as hasten dementia-related cognitive impairment. 

Worse still, decongestants can interfere with prescription blood pressure medication, according to Pharmacy Times. Accordingly, if you intend to take cough medicine on a daily basis, it's best to avoid those containing decongestants.

Taking cough medicine every day may also interfere with your healthcare. To the extent your cough medicine effectively suppresses your cough, for example, you may be less inclined to bring your cough to your doctor's attention, at least until tolerance escalates, at which point symptoms return. Meanwhile, if your coughing is caused by an underlying condition (e.g., infection, GERD, COPD, vasculitis, lung cancer, according to the Mayo Clinic), then your daily cough medicine usage may be delaying you getting the care you require. 

Conversely, some of the adverse effects associated with cough medicine abuse/overuse may be identical to symptoms of serious illness. For example, chronic use of cough medicines containing guaifenesin can cause uric acid levels to decrease. Because decreased uric acid levels may be symptomatic of serious illness, including Huntington's, Alzheimer's, and multiple sclerosis (via SelfDecode Labs), your cough medicine usage may lead to unwarranted alarm — not to mention, fruitless and expensive medical testing. 

Likewise, some of the adverse effects associated with daily use of DXM-containing cough medicine are associated with other serious health conditions, which can lead to needless scrambling and time wasted by healthcare providers. For example, a 2011 case study published in Pediatric Emergency Care describes the lengthy wild goose chase that resulted when a teen suffering from DXM abuse presented in the ER with seizures — before proposing a recommendation be made that emergency medicine professionals consider DXM abuse as a possible cause of seizures in young patients.