Triple C’s is a street name for Coricidin HBP Cough & Cold, an over-the-counter cold medication that is widely misused for its dissociative, hallucinogenic effects. The name comes from the three C’s in “Coricidin Cough and Cold.” Each tablet contains 30 mg of dextromethorphan (a cough suppressant known as DXM) and 4 mg of chlorpheniramine (an antihistamine). While both ingredients are safe at recommended doses, taking large quantities produces a high that users compare to ketamine or PCP, and the combination creates overlapping toxicities that make Triple C’s one of the more dangerous forms of DXM abuse.
Why This Specific Product Gets Misused
Coricidin HBP is formulated for people with high blood pressure. Unlike most cold medicines, it contains no decongestant, which means no pseudoephedrine or phenylephrine. That makes it a safer cold remedy for its intended audience, but it also means each tablet is a compact, easy-to-swallow dose of DXM without the nausea-inducing syrups or bitter liquids found in other cough products. The small red tablets are easy to carry and consume in large numbers, which is a big part of why they became a go-to for recreational abuse, particularly among teenagers.
What DXM Does at High Doses
At the recommended dose of 10 to 30 mg every few hours (no more than 120 mg per day), DXM simply suppresses your cough reflex. At recreational doses ranging from 300 to over 1,500 mg, it blocks a type of brain receptor involved in perception, memory, and consciousness. The result is a dissociative state: a feeling of detachment from your body and surroundings, distorted senses, and hallucinations.
Users describe the effects in four escalating stages, sometimes called “plateaus,” based on how much DXM is consumed relative to body weight:
- Plateau 1 (roughly 100 to 200 mg, or 4 to 6 tablets): Restlessness and mild euphoria, similar to a stimulant buzz.
- Plateau 2 (200 to 500 mg, or 7 to 18 tablets): Exaggerated sounds and visuals, closed-eye hallucinations, loss of balance.
- Plateau 3 (500 to 1,000 mg, or 18 to 33 tablets): Significant visual and auditory disturbances, altered consciousness, mania, panic, and partial dissociation from reality.
- Plateau 4 (over 1,000 mg, or more than 33 tablets): Full hallucinations, delusions, complete dissociation, and loss of motor control.
Effects typically begin within an hour of ingestion. DXM also interferes with the brain’s handling of serotonin and adrenaline, which can spike blood pressure, cause heavy sweating, and raise body temperature.
The Added Danger of Chlorpheniramine
This is what makes Triple C’s particularly risky compared to other forms of DXM abuse. Every tablet also delivers 4 mg of chlorpheniramine, a first-generation antihistamine. Someone swallowing 15 to 30 tablets to reach a DXM high is simultaneously taking 60 to 120 mg of chlorpheniramine, far beyond the safe range.
At those levels, chlorpheniramine causes a condition called anticholinergic toxicity. The classic signs are sometimes described with a medical mnemonic: flushed skin, inability to sweat, dangerously high body temperature, blurred vision, hallucinations and delirium, and inability to urinate. These symptoms layer on top of DXM’s own dissociative effects, creating a confusing and dangerous situation where the person may not recognize how much trouble their body is in.
Anticholinergic toxicity can also affect the heart. It may cause a rapid heartbeat, abnormal heart rhythms, and changes in blood pressure. Seizures can occur within one to two hours of ingestion. In severe cases, muscle breakdown (rhabdomyolysis), respiratory failure, and coma are possible. The combination of two drugs both capable of producing hallucinations, seizures, and cardiovascular stress is what makes Triple C overdoses especially unpredictable.
Serotonin Syndrome Risk
DXM increases serotonin activity in the brain, which creates a specific and serious risk for anyone taking antidepressants or certain other medications. When serotonin levels climb too high, the result is serotonin syndrome: a potentially life-threatening condition marked by agitation, rapid heart rate, high blood pressure, muscle rigidity, and dangerously elevated body temperature.
The list of medications that can interact with DXM to trigger this reaction is long. It includes SSRIs (common antidepressants like sertraline and fluoxetine), tricyclic antidepressants, MAO inhibitors, certain pain medications, anti-nausea drugs, migraine medications, and even some herbal supplements. A person taking any of these who then consumes a large amount of Triple C’s faces a compounded risk that neither drug would produce alone.
Signs of an Overdose
A Triple C overdose is a medical emergency. Because both active ingredients affect the brain and cardiovascular system, the warning signs can escalate quickly. Key symptoms include slow or shallow breathing, bluish fingernails or lips, seizures, a pounding or unusually fast heartbeat, muscle twitching, vomiting, and loss of consciousness. Body temperature may spike because both drugs impair the body’s ability to cool itself. Blurred or double vision, extreme drowsiness, and an unsteady or stumbling walk are also common.
Young people may not recognize these symptoms as dangerous, especially when the hallucinations and confusion from the drugs make it hard to assess what’s happening. Bystanders who see someone unresponsive, breathing irregularly, or seizing after taking Triple C’s should treat it as a poisoning emergency.
Long-Term Effects of Repeated Use
Chronic DXM abuse has been linked to lasting cognitive decline. Case reports document deterioration in memory, attention, and mental processing speed in people who used DXM heavily over extended periods. The combination with repeated chlorpheniramine exposure, which is itself sedating and neurotoxic at high doses, likely worsens the picture, though large-scale studies on Triple C’s specifically are limited.
Repeated anticholinergic exposure is also associated with increased risk of dementia in older populations, raising concerns about what sustained high-dose use during adolescence, when the brain is still developing, might mean over a lifetime. The cardiovascular strain from repeated overdoses, including irregular heart rhythms and blood pressure swings, adds another layer of cumulative risk.