What is Dextromethorphan Toxicity?
Dextromethorphan is an active ingredient found in many cough and cold medicines you can buy without a prescription. It’s used to suppress coughs and comes in various forms like oral strips, lozenges, and liquid capsules. Often it’s combined with other ingredients like guaifenesin, acetaminophen, and pseudoephedrine. On the flip side, dextromethorphan is also commonly misused for the ‘high’, hallucinations, and out-of-body experiences it can cause. It’s known by various street names like “Triple C,” “Dex,” “Orange Crush,” “Red Devils,” and “Poor Man’s PCP.”
The harmful effects of dextromethorphan overdose can range widely, impacting the heart, brain, metabolism, and muscles, based on the amount taken. Therefore, emergency healthcare providers should be well-versed in identifying and managing dextromethorphan toxicity. Some of the potential complications of misuse include high blood pressure, seizures, rapid heart rate, psychosis, and a harmful muscle condition called rhabdomyolysis.
What Causes Dextromethorphan Toxicity?
Using dextromethorphan incorrectly or taking too much can lead to dextromethorphan toxicity.
Risk Factors and Frequency for Dextromethorphan Toxicity
Dextromethorphan, a medication used in many cough and cold remedies, got FDA approval in 1958. Not long after, people began to misuse it for recreational purposes. In response, drug companies created liquid versions, so a person would have to consume a large amount to feel any effects on the central nervous system. Still, misuse did not decrease. In the U.S., dextromethorphan abuse causes around 6,000 emergency department visits each year. Half of these are patients aged between 12 and 20.
Dextromethorphan is often mixed with other drugs like antihistamines, pseudoephedrine, and acetaminophen in many cold and cough medications. When taken in excess, the combination can cause harmful side effects. Ethanol, or alcohol, is also commonly used with it. Some people try to extract the dextromethorphan from these mixtures using a one or two phase acid extraction method, which involves household items like ammonia, lighter fluid, and lemon juice.
Signs and Symptoms of Dextromethorphan Toxicity
Using too much dextromethorphan, a common ingredient in cough syrups, can lead to a wide variety of side effects. These can be as mild as feeling restless or as severe as experiencing psychotic episodes, seizures, or even falling into a coma. Sometimes, people under the influence of this substance might not be able to clearly express what’s happening due to changes in their mental state. This is where information from friends, family, or emergency responders becomes important. Knowing the street names used for dextromethorphan can also be very helpful.
The potential side effects include:
- General symptoms: high body temperature, sweating, altered mental state (which can vary from mild restlessness to a coma)
- HEENT symptoms: dilated pupils, involuntary eye movement
- Heart-related symptoms: fast heartbeat, high blood pressure
- Respiratory symptoms: slowed breathing
- Neurological symptoms: restlessness, confusion, hallucinations, lack of coordination, muscle stiffness, seizures, coma
It’s also important to check for signs of physical injury, as someone under the influence of dextromethorphan may have fallen or hurt themselves due to an altered mental state.
Testing for Dextromethorphan Toxicity
If you’re feeling unwell and your doctor suspects that it may be due to an overdose of dextromethorphan – an active ingredient commonly found in cough syrups and cold medications – you may need to undergo various tests. These can include:
- Dextromethorphan level: This test measures the amount of dextromethorphan in your body, but it might not be available at many hospitals.
- Fingerstick blood glucose: This quick finger prick test measures your blood sugar levels, which is useful for anyone experiencing confusion or altered mental clarity.
- Complete blood count: This test looks at the cells in your blood. An increased number of white blood cells could be a sign of an infection or other medical condition.
- Basic metabolic panel: This series of tests checks your body’s chemical balance and metabolism – particularly your kidney function. This is important because dextromethorphan primarily gets expelled from your body via your kidneys.
- Liver function tests: These tests measure various proteins and enzymes in your liver. Acetaminophen, which is often combined with dextromethorphan in many medications, has the potential to harm your liver.
- Creatine kinase: This test measures the level of the enzyme creatine kinase in your blood, to check for a condition called rhabdomyolysis (the breakdown of muscle tissue).
- Acetaminophen level: This checks the amount of acetaminophen in your body. Like dextromethorphan, acetaminophen is often combined in many medications.
- Salicylate level: This can be valuable to check in patients experiencing acid-base imbalance in the blood or confusion.
Additionally, an ethanol level test can help detect alcohol in your bloodstream, which can be useful if your mental clarity is altered, and especially if you might have been taking dextromethorphan with alcohol.
Your doctor might also request an EKG (a test that measures heart activity) to check for rapid heart rate. If there are concerns about possible injury or inhalation of food or fluid into the lungs due to dextromethorphan toxicity, imaging studies might be recommended.
A urine drug screen can help identify if any other potentially harmful substances have been consumed along with dextromethorphan.
Treatment Options for Dextromethorphan Toxicity
For patients with dextromethorphan toxicity, the main form of treatment is supportive care. This involves ensuring a good flow of air and blood in the body, closely monitoring heart activity, and potentially using a ventilator to assist with breathing, if needed. Expert advice from a medical toxicologist is also important in these situations.
Some patients might become agitated or display violent behaviour due to the toxicity. To control these effects, medication and physical restraints may be used, and placing the patient in a calm environment (like a quiet, dimly lit room) can also help. The medication of choice for calming or sedating patients is usually benzodiazepines, specifically lorazepam, which can be given via an injection into a muscle or a vein.
If the patient ingested dextromethorphan, activated charcoal is usually most effective in tackling this if given within an hour of ingestion. It can be administered by mouth or a nose-to-stomach tube. However, induced vomiting or stomach pumping are not recommended.
Naloxone, a medicine used to counteract opioid overdose, can help treat breathing and central nervous system issues due to dextromethorphan toxicity. If the patient becomes hyperthermic (overheated), the medical team may use active cooling measures such as cool intravenous fluids.
It’s crucial to remember that dextromethorphan is usually combined with acetaminophen, decongestants, and antihistamines in many cough and cold medicines, so checking and treating for toxicity from these substances should also be considered.
Patients with dextromethorphan toxicity can typically be sent home if they’ve been symptom-free for six hours after ingesting the substance, are not at risk of self-harm, and show no signs of acetaminophen toxicity. Those who remain symptomatic or experience complications such as overheating, serotonin syndrome, extreme high blood pressure, or muscle breakdown should be admitted to the intensive care unit (ICU). Suicidal patients should also receive a psychiatric consultation.
What else can Dextromethorphan Toxicity be?
When a doctor wants to determine what is causing someone’s symptoms, they might consider the following possible conditions:
- Being intoxicated from alcohol
- Being intoxicated from drugs, like amphetamines or cocaine
- Poisoning from anticholinergic substances or diphenhydramine
- Bipolar disorder or schizophrenia
- Brain tumors
- Withdrawal symptoms from alcohol, known as delirium tremens
- Encephalitis, which is inflammation of the brain
- Hyperthyroidism, which means an overactive thyroid
- Low blood sugar, also known as hypoglycemia
- Low sodium in the blood, also known as hyponatremia
- Low oxygen levels in the body, called hypoxia
- Toxicity from substances like LSD (Lysergic acid diethylamide) or MDMA
- Conditions like malignant hyperthermia or neuroleptic malignant syndrome
- Serotonin syndrome, a potentially life-threatening condition
- Poisoning from too much aspirin (salicylate)
- Poisoning from toxic alcohols
- Injuries, either self-inflicted or accidental
- Brain infections like meningitis or encephalitis
- Sepsis, a life-threatening infection
- Excessive ingestion of certain antidepressants, known as SSRI toxicity
It is important for the healthcare provider to carefully consider these possibilities and perform the necessary tests to make an accurate diagnosis.
What to expect with Dextromethorphan Toxicity
Dextromethorphan toxicity, or poisoning, usually requires supportive care for effective treatment. This means ensuring key essentials like the patient’s airway, breathing, circulation, and monitoring of vital signs, including heart function. In some serious cases, a patient may need to be put on a ventilator, which involves a process called intubation to protect the patient’s airway.
Possible Complications When Diagnosed with Dextromethorphan Toxicity
Possible adverse reactions or health risks can include:
- Seizures
- Emergency increases in blood pressure
- Coma
- Serotonin syndrome (a group of symptoms caused by high levels of the chemical serotonin in the brain)
- Rhabdomyolysis (a condition that can cause kidney damage due to the breakdown of muscle tissue)
- Psychosis (loss of contact with reality)
- Breathing depression or stoppage
Preventing Dextromethorphan Toxicity
It’s crucial that all patients are informed about the potential risks associated with a medication called dextromethorphan. Additionally, parents should be advised to keep this medicine stored in a place where children cannot easily access it to ensure their safety.
