Overdosing on Cold and Flu Medications

Intentional and Unintentional

Over-the-counter (OTC) cough and cold medicines are widely available, low-cost, and can help relieve some symptoms of upper respiratory infections and the flu. While they have some benefits, these medications carry a risk of overdosing.

Overdosing of OTC cold and flu remedies is often accidental—due to errors like misreading product labels or dosing. Sometimes, these medications are also intentionally abused.

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How an Accidental Overdose Happens

Overconsumption of drugs found in cold and flu remedies, such as acetaminophen, non-steroidal anti-inflammatories, dextromethorphan, pseudoephedrine, and antihistamines, pose health risks. Using these medications with alcohol can also lead to overdosing.

There are several reasons that accidental overdoses can happen with these medications.

Overdosing on OTC cold and flu medications can happen when someone ignores dosing recommendations and takes whatever dose they deem necessary. Some people may take larger or more frequent doses in an effort to overcome illness faster.

And people may misread a product label or measure the dose incorrectly due to simple human error.

Taking different OTC cold and flu remedies can cause an overdose if they contain some of the same ingredients. For example, if you were to take a multi-symptom medication like NyQuil along with Tylenol (or Tylenol Extra Strength) for fever and pain, you could overdose on acetaminophen, which is in both products.

Taking too much acetaminophen can potentially cause liver damage. This risk is even higher with alcohol. According to research published in the Journal of Clinical and Translational Hepatology, acetaminophen overdose accounts for more than 50% of overdose-related acute liver failures in the United States.

Ways to avoid these mistakes include:

  • Read the product labels
  • Avoiding co-administration of remedies with the same ingredients
  • Limit yourself to the recommended dose
  • Don't drink alcohol when you've been taking cold and flu medications

Cold/Flu Medicines and Kids

A 2015 report in the journal Pediatrics in Review concluded that OTC preparations are no more effective in treating cough and cold symptoms compared to placebo and that the products have not been proven to be safe and effective in young children.

The U.S. Food and Drug Administration (FDA) asserts that most children will recover from cold and flu on their own without the need for medicine and advises against the use of these medications in children under four years old unless a doctor specifically tells you to do so.

Signs of Accidental Overdose

Though you may never anticipate a cold and flu medication overdose, they can easily happen. It's important to recognize the signs of overdose.

Symptoms of a potential overdose of OTC cold and flu medication include:

  • Excessive tiredness or lethargy
  • Extreme dizziness or drowsiness
  • Sudden anxiety or jitteriness
  • Confusion
  • Abdominal pain
  • Labored or shallow breathing
  • Loss of appetite
  • Nausea or vomiting
  • Rapid heart rate
  • Blurred vision
  • Dilated pupils
  • Dark-colored urine
  • Unresponsivenessness

Call Poison Control at 1-800-222-1222 and seek emergency care if you think you've given yourself or your child too much cold and flu medication.

Medication Abuse

In the past, codeine and alcohol contained in many OTC cough syrups were abused.

As a public health safety measure, alcohol is not a component of most OTC remedies, while codeine has been classified controlled substance. Products containing 90 mg or more of codeine, like Tylenol 3, are Schedule III controlled substances.

Some people abuse OTC cold, cough, and flu remedies containing dextromethorphan (DMX). These products are readily available throughout the United States in syrup, tablet, and powder form.

The abuse of DMX is most common among 8th to 12th graders. When swallowed or snorted in excess, DMX can cause hallucinogenic effects similar to the anesthetic drug ketamine or the street drug phencyclidine (also known as PCP or "angel dust.") Depending on how much is taken, the effects can last for as long as six hours or even more.

The overuse of DMX is associated with an array of side effects, including:

  • A feeling of floating
  • Confusion and disorientation
  • Impaired judgment
  • Blurred vision
  • Loss of coordination
  • Slurred speech
  • Dizziness
  • Excessive sweating
  • Hyperactivity
  • Hallucinations
  • Rapid or pounding heartbeats
  • A drop in body temperature
  • Hot flashes
  • Diarrhea
  • Abdominal pain
  • Nausea and vomiting
  • Unconsciousness

An overdose of DMX can lead to more serious symptoms, including seizures, cerebral hemorrhage (bleeding in the brain), permanent brain damage, and even death.

Repeated abuse of DXM at high doses can also cause a condition known as chemical psychosis in which a person loses touch with reality. Referred to by some as "poor man's psychosis," the DMX-induced disorder (characterized by paranoia, delusions, hallucinations, and disassociation) has been known to lead to impulsive and even violent acts, including assault and self-harm.

Signs of Cold/Flu Medication Abuse

Since DMX abuse is largely hidden, it is important to recognize the signs of overdose.

If you suspect that someone has overdosed on DMX, call 911 if there are any of the following symptoms:

  • Extreme disorientation or drowsiness
  • Blueish lips, fingernails, or skin
  • Vomiting
  • Seizures
  • Very slow or very rapid heartbeats
  • Slow, shallow, or labored breathing
  • Unconsciousness
  • No breathing

Until help arrives, call Poison Control 1-800-222-1222 for instructions on what to do.

A Word From Verywell

To prevent abuse in your family, educate your kids about the dangers of DMX, monitor their activities, keep track of all cold and flu medications in the home, and avoid stockpiling medications containing DMX. And if you're self-treating a cold, be sure to carefully read and follow product instructions and only treat the symptoms you have.

Frequently Asked Questions

  • How much NyQuil can cause an overdose?

    For NyQuil Cold and Flu Nighttime Relief, do not take more than four doses in 24 hours. See the directions on the box for the correct dosage for adults and children.

  • What should you do if you overdose on cold and flu medicine?

    In cases of overdose, get emergency medical help or call Poison Control at 1-800-222-1222. It's important to get immediate medical care, even if you don't notice any symptoms yet.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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  2. Yoon E, Babar A, Choudhary M, Kutner M, Pyrsopoulos N. Acetaminophen-induced hepatotoxicity: A comprehensive updateJ Clin Transl Hepatol. 2016;4(2):131-42. doi:10.14218/JCTH.2015.00052

  3. Lowry JA, Leeder JS. Over-the-counter medications: Update on cough and cold preparations. Pediatr Rev. 2015;36(7):286-97. doi:10.1542/pir.36-7-286

  4. U.S. Food and Drug Administration. When to give kids medicine for coughs and colds.

  5. U.S. Drug Enforcement Agency Diversion Control Division. Title 21 United States Code (USC) Controlled Substances Act: Section 812 Schedule of controlled substances.

  6. Antoniou T, Juurlink DN. Dextromethorphan abuseCMAJ. 2014;186(16):E631. doi:10.1503/cmaj.131676

  7. Martinak B, Bolis RA, Black JR, Fargason RE, Birur B. Dextromethorphan in cough syrup: The poor man's psychosisPsychopharmacol Bull. 2017;47(4):59-63.

  8. U. S. National Library of Medicine. DailyMed. Vicks NyQuil Cold and Flu Nighttime Relief.

By Kristina Duda, RN
Kristina Duda, BSN, RN, CPN, has been working in healthcare since 2002. She specializes in pediatrics and disease and infection prevention.