DXM Side Effects: Is It Safe During Pregnancy And Dangers of Overdose

Last Updated: July 5, 2021

Reviewed by Michael Espelin APRN

Dextromethorphan (DXM) falls under the drug class antitussives and its main use is a cough suppressant. This drug is a cold medicine, useful for the treatment of colds and flu. Although this medicine is safe and effective to use by adults at a therapeutic dose, there is still a risk for overdose, and pregnant women should consult a doctor first before taking it. In the United States, those individuals of ages 12 to 20 years old get a higher rate (8 per 100,000) of emergency room visits compared to the other age groups. In this article, information about the DXM side effects, the safety of DXM while pregnant, dangers of overdose to the health, and the treatment choices for patients such as medical therapy and rehabilitation will be provided.

The Most Common DXM Side Effects

In 2018, the number of users of Dextromethorphan in the United States is estimated to be around 320,000. Dextromethorphan is used as a cough suppressant and the effects of its use last for 5 to 6 hours. During this time, it is possible for common side effects to occur. Although this drug can be bought over-the-counter, it is important for every patient to know the following common short-term DXM side effects such as restlessness and irritability. Additionally, DXM side effects affect not only the mind but also the physical health of a patient. So, even when patients use this drug properly, some common physical short-term side effects may occur such as fatigue.

The exact type of adverse reaction depends on the dose. Dextromethorphan may show some common, psychological long-term side effects to the health such as psychosis and physical long-term DXM side effects such as decreased sexual functioning and immobilization. Even though some of the side effects are considered common, it is always advisable for every patient to share their experiences with a doctor as this is a way to improve and care for the health of the patient. Unwanted DXM side effects may be experienced especially when the drug is misused and sometimes, these can last for the rest of a patient’s life which can be dangerous.

Person having flu, fever and headache on sofa couch.

DXM Short-Term Effects

Depending on the dose, this drug may produce common short-term and long-term DXM effects. The most immediate short-term DXM effects of this drug when a patient have used a low to moderate dose are:

  • dilated pupils
  • constipation
  • sleepiness (or even lethargy)
  • slurred speech
  • other alcohol-like symptoms
  • Numbness
  • Changes in sensory perceptions
  • Hallucination

Dextromethorphan is a safe and effective cough suppressant and cold medicine and when it is used properly at a low dose, only common DXM effects may be seen. However, at high doses, it can produce dangerous DXM effects such as seizures and muscle contractions. If a patient is experiencing these effects, it is important to reach out to a doctor and seek medical help even if these side effects are considered short-term.

DXM Long-Term Effects

Dextromethorphan is one of the dissociative drugs. These drugs produce a sense of floating and dissociation from reality. Dissociative drugs work by disrupting the actions of the brain chemical glutamate (which plays a role in cognition) at certain types of receptors throughout the brain. DXM long-term effects cause an order of magnitude more negative reactions. The study on cognitive deterioration from long-term abuse warns that prolonged consumption of this cough and cold syrup drug affects all aspects of cognitive functioning and may cause the next DXM long-term effects:

  • short and long-term memory
  • problem-solving skills
  • reaction time
  • feeling “keyed up” or tense
  • depression
  • emotional instability (which is so prominent sometimes, that long-term abuse is mistakenly diagnosed as Bipolar Disorder)

These symptoms are linked with DXM brain damage. Persistent delusional disorder is one of the worst DXM long-term effects; in these cases, hallucinations and delusions of persecution can be expected. Although this drug works on the brain, it also produces physical DXM long-term effects especially at high doses such as physical distress, including dangerous health changes like blood pressure.

Rare Side Effects Of DXM

Most adverse drug reactions are dose-dependent; otherwise, they are allergic or idiosyncratic. The incidence of severe or fatal adverse DXM drug reactions is very low. However, Rare or Uncommon Side Effects of This Drug That Are Dangerous to the Health May Be the Following:

  • Coma
  • Hyperthermia
  • High blood pressure

Since high blood pressure is mentioned above, individuals with other health conditions such cardiac problems should keep this in mind before deciding to use the drug. According to a report, 5 individuals have died after using Dextromethorphan which was bought over the Internet.

Factors That Impact the Side Effect Emergence

Aside from taking alcohol or smoking while taking a certain medication, many factors play a crucial role in the appearance of the DXM side effects. The Factors That Cause the Emergence of Side Effects:

  • Age – extreme ages (young and old patients) are the most vulnerable side effects compared to other age groups. This means that more side effects can be seen when a patient taking this drug is under these extreme ages.
  • Gender – a patient’s characteristics including race is also a factor. For example, a male and female have different enzyme capabilities.
  • Multiple drugs – patients who take multiple drugs are prone to drug interactions which may cause additional side effects.
  • History of adverse drug reaction – those with allergy to certain drugs may experience worse side effects.
  • Dosage – consumption of large doses may possibly bring more adverse effects and dangers to the health.
  • Pregnancy – psychological changes occur during pregnancy and this may affect how the body reacts to the drug.

Indeed, different factors affect how a drug gives out its side effects. Because of this, serious attention to these factors will help a patient avoid such worse reactions. Additionally, consider reaching out to a doctor to get medical help to avoid the occurrence of side effects.

Depressed girl holds DXM meds.

The Safety Of DXM During Pregnancy

When it comes to DXM and pregnancy, there are no reports or information on the harmful effect on a parent or a baby when taking antitussives like DXM while pregnant. So, even though Dextromethorphan is considered a pregnancy category C drug, the lack of controlled data in human pregnancy makes it even harder to keep track of results in changes experienced when taking the drug. So, if patients are wondering if this drug is safe for pregnancy, they might be right as it will produce minimal or no Dextromethorphan allergy.

The health of a baby is very important during pregnancy. Recent studies also have indicated that pregnant women do not have to worry about taking DXM while pregnant. According to the research done by the National Center for Biotechnology Information (NCBI) on the safety of this drug during pregnancy, they were able to ascertain the outcome in about 184 women. The study recorded live births, unpremeditated abortions, diagnostic abortion, and stillbirth. Most of the women used pure Dextromethorphan during the first trimester of their pregnancy. The results of this research failed to show that the use of Dextromethorphan during pregnancy increases and affects the rates of major malformations above the known baseline rate of 1-3%.

Using Dextromethorphan While Breastfeeding

Based on its low molecular weight, Dextromethorphan passes into breast milk almost anytime. If it is administered during pregnancy, it may be passed on to the baby. But, neither the absorption of Dextromethorphan in milk nor its effects on breastfed infants have been studied thoroughly. According to a study, it is unlikely that a usual dose of breast milk would cause adverse DXM effects or harm to the health of the nursing infant, especially to a baby above two months of age. Some DXM-containing products include alcohol. If one needs to use Dextromethorphan while breastfeeding, better to select a product that does not have any form of alcohol. Contact the personal healthcare provider for any questions about the safety of this drug while nursing.

DXM Overdose And the Dangers of DXM Misuse

Although Dextromethorphan is considered a safe drug, taking an excessive amount can lead to overdose which is dangerous to one’s health. According to the patent of the product, the maximum dosage as an antitussive is 120mg. However, how much Dextromethorphan is needed to overdose might be affected by a person’s metabolism. Furthermore, the presentation might vary in how much suspension or many tablets are taken. Nevertheless, the amount for Dextromethorphan polistirex overdose and Dextromethorphan HBr overdose is similar, as generally, the metabolism of the drug is not significantly different. In 2007, there is a prevalence in the use of Dextromethorphan in the United States, and these people who abuse the medication are teens. For this reason, the Washington State Department of Health implements a policy that teens cannot buy this drug without their parents.

Signs And Symptoms Of DXM Overdose

DXM overdose symptoms can go from mild to severe. The symptoms can vary depending on the amount of medication taken as well. The intensity also changes depending on the individual metabolism and mixing with other substances.

The Most Common Signs of Overdose on Dextromethorphan:

  • nausea
  • vomiting
  • palpitations
  • muscle twitches
  • pupillary dilation
  • stomach spasms
  • dizziness
  • extreme changes in blood pressure
  • seizures

Taking too much Dextromethorphan is easily preventable. If a medical professional recommended Dextromethorphan, following the instructions is the first step in achieving this. In the case of an emergency when the extreme amount of Dextromethorphan taken is an alarm, and heading to a rehab facility can be vital. To prevent such incidents among adolescents, parents, and teachers should conduct informative conversations. It is also advisable for parents to make a policy inside their household about drug abuse. Anyone showing DXM overdose symptoms requires medical attention. DXM overdose treatment might vary depending on the protocol followed by each hospital. Only medical professionals know how to treat DXM overdose properly.

DXM Tolerance And the Risk of Overdose

Dextromethorphan tolerance ensues when a person happens to take the drug constantly for a long time. Medication interacts with the brain chemistry, and in time, it can get used to the DXM effects. While OTC Dextromethorphan cough drops are generally safe, any other Dextromethorphan products may lead to DXM tolerance, overdose, and other serious complications to the health of the patient. Tolerance to Dextromethorphan occurs when a person experiences a reduced reaction to a drug. This results in users needing to administer higher doses of Dextromethorphan to achieve the desired DXM effects.

Unlike addiction, Dextromethorphan tolerance is not considered a disease. Users who can’t stop taking Dextromethorphan despite experiencing its negative consequences have an addiction. Knowing how long it takes to build up a tolerance to Dextromethorphan can help an individual avoid getting used to the drug. However, the DXM tolerance timeline may differ from one person to another.

Several Factors May Affect How Fast One Can Build a Tolerance to Dextromethorphan:

  • The age and weight of the patient. While Dextromethorphan LD50 has been established, genetics will still play a huge role
  • The drug form used. For example, how much Dextromethorphan is in Delsym can greatly affect metabolism and the development of tolerance. This specific form contains polistirex as its active ingredient, which is time-released. Its effect can last for up to 12 hours, making it more potent when used recreationally
  • The period of consumption
  • User’s expectations for the drug
  • The environment where the individual consumes the drug
  • The overall level of tolerance to other drugs
  • Potential drug interactions

While individual factors may still play a role in how long for DXM tolerance to go down, it generally takes about 3 to 7 days for the tolerance to be reduced by 50%. It can be back at baseline within a week or two, provided that there is a complete DXM tolerance break or no further consumption. According to the American Association of Poison Control Center, due to misuse of Dextromethorphan by teenagers in 2003, the United States Department of Justice has started to make a policy about the marketing of Dextromethorphan.

A doctor gives prescription to a patient.

DXM Tolerance Symptoms

According to a study, a patient who is a long-term user of this drug is at risk of developing DXM tolerance. Tolerance may occur when a person is abusing the drug or when consuming an escalated dose of Dextromethorphan. One reason why people are possibly ingesting an increasing amount of the dose is that they are not getting the desired effects. However, doing this will only lead to tolerance.

These Characteristics Can Indicate That a Person Has Developed Tolerance to This Medication:

  • The person needs to increase the dosage every time
  • The effects of Dextromethorphan wear off rapidly
  • Dextromethorphan craving is evident in between doses
  • Some signs of withdrawal appear once the drug effect fades away

Instead of conducting a Dextromethorphan reverse tolerance, most people tend to increase their intake until their body starts craving for more. Approximately 33-50% of people who experiment with Dextromethorphan develop tolerance and go on to abuse it regularly. The tolerance which is caused by the Dextromethorphan class of drug may be turned into an addiction. It will require immediate medical intervention and treatment from experts in drug rehab facilities. Proper substance abuse treatment options will help people address the problems that drive their behaviors, rectify these issues, learn coping skills, and develop a long-term plan for sobriety

The Therapy and Rehabilitation for DXM Side Effects

Dextromethorphan is a cough suppressant that is safe and effective to use according to the National Drug Intelligence Center. Also, this drug can be considered as a cold medicine. Like any other drugs, Dextromethorphan has common short-term and long-term side effects and these are affected by many factors. Aside from DXM brain damage, side effects can also be seen physically and this is a reason why it is important to reach out to a doctor whenever a patient is experiencing them, especially the rare ones. When it comes to DXM and pregnancy, this drug is safe to use. However, a pregnant or breastfeeding mom should consult a medical professional first before taking this drug for additional purposes. Even if this drug is safe to use, there is a possibility for an overdose to occur. Since Dextromethorphan is an OTC drug, it is recommended for pharmacies to consider making a policy when selling this medication and one way is by verifying the age of the buyer.

When it comes to the treatment, the side effects of medication can be treated with a plethora of substance abuse treatment options. Cognitive Behavioral Therapy might help individuals with Dextromethorphan depression. Furthermore, a patient may go into a rehabilitation facility or center to treat chronic cases of Dextromethorphan abuse. A combination of psychotherapy and institutionalization is advised for individuals that exhibit extreme symptoms of addiction.

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Published on: August 6th, 2019

Updated on: July 5th, 2021

About Author

Peter J. Grinspoon, MD

Dr. Peter Grinspoon is an experienced physician with long-term clinical practice experience. As a former analgesic addict, Dr. Grinspoon knows precisely how important it is to provide patients with effective treatment and support. Medical writing for him is the way to communicate with people and inform them about their health.

Medically Reviewed by

Michael Espelin APRN

8 years of nursing experience in wide variety of behavioral and addition settings that include adult inpatient and outpatient mental health services with substance use disorders, and geriatric long-term care and hospice care.  He has a particular interest in psychopharmacology, nutritional psychiatry, and alternative treatment options involving particular vitamins, dietary supplements, and administering auricular acupuncture.