A 24-year-old man presented come the emergency room with altered sensorium. He was awake, alert, and also oriented to person and place only, v erratic, dissociative behavior, consisting of hallucinations. He had actually been given naloxone in the field, which had resulted in mild improvement.

You are watching: Will dextromethorphan make you fail a drug test

On physics examination, the patient remained in hypertensive urgency, with a blood pressure of 209/118 mm Hg. His mood to be euphoric and also hyperalert, through inappropriate laughing. He was hallucinating. He to be agitated and also diaphoretic. His pupils to be dilated and also equally reactive, with vertical and also horizontal nystagmus. Mucous membranes were dry. His Glasgow Coma scale score was 14 of 15. No focal length neurologic deficits were appreciated. Cardiac examination revealed just sinus tachycardia, through the beats every minute in the 120s._________________________________________________________________________________________________________________________________________________________Related ContentThe Potential effect of Marijuana and Tobacco on Warfarin Metabolism and also INRMarijuana use Can readjust Brain"s physics Structure________________________________________________________________________________________________________________________________________________________

Results of laboratory studies verified hypokalemia (2.5 mEq/L potassium), acute renal insufficiency (creatinine clearance, 1.8 mg/dL; baseline, 1.0 mg/dL), and also elevated creatine kinase (2400 U/L).

Computed tomography scan that the head revealed no acute findings. Electrocardiography revealed sinus tachycardia. Chest radiography revealed no acute pulmonary findings. Results of a urine toxicology display were hopeful for phencyclidine (PCP) and also marijuana.

He received a presumptive diagnosis that PCP intoxication and also was managed with intravenous fluids, benzodiazepines, electrolyte replacement, antihypertensives, and soft restraints as needed.

See more: Where Is The Buccinator Muscle Located, Buccinator Muscle

Overnight, his condition improved. His electrolyte level normalized, and his renal function returned to baseline. His mentation cleared, and also when he was interviewed the following morning, he denied the usage of PCP yet admitting come taking around 10 pills of a Coricidin HBP product (containing dextromethorphan) the night prior to to “get high.”



Dextromethorphan is one over-the-counter (OTC) cough suppressant that is typically used as a entertain drug amongst young adults. The is one isomer that codeine and shares a similar chemical structure to PCP (Figure).1 Its active metabolite is dextrorphan, an N-methyl-d-aspartate (NMDA) receptor antagonist, i m sorry in cases of intoxication leader to a unique combination of hallucinations, out-of-body sensations, dissociation, and inhibition the adrenergic reuptake. This in turn leads come tachycardia, hypertension, and diaphoresis.1

In addition to dextromethorphan, OTC cough formulations commonly contain various other agents such together the antihistamine chlorpheniramine. Coingestion of dextromethorphan and also antihistamines leads to attributes of anticholinergic poisoning, such as tachycardia, hypertension, hyperthermia, flushing, warm and also dry skin, and agitated delirium.2 Hyperthermia, agitation, seizures, and also muscle rigidity may cause rhabdomyolysis and also renal failure.2 Serotonin syndrome have the right to complicate the presentation.2

Approximately 1 million united state young adult misuse OTC cough and also cold drugs containing dextromethorphan every year.3 The brands Coricidin, Nyquil, and Robitussin account for nearly 66% of such situations of misuse.3 Furthermore, young adults frequently simultaneously use marijuana with dextromethorphan-containing products.4

Testing because that dextromethorphan gulp down is difficult, because rapid to pee drug display screens do no detect it; thus, the diagnosis typically is based upon the patient’s history and clinical findings.5 Moreover, dextromethorphan can reason a false positive result for PCP on fast urine medicine screens,1,6 due to the fact that dextromethorphan and also PCP space both NMDA receptor antagonists, are dopamine agonists, and inhibit serotonin reuptake, and also because the screening test for PCP provides an antibody through a structure comparable to dextromethorphan.1,7

Tulisa LaRocca, MD, is one affiliated assistant professor of medication at the university of Miami Miller institution of Medicine, Palm Beach regional Campus, in Atlantis, Florida.