Over-the-counter cough and cold preparations: Approach to pediatric poisoning

INTRODUCTION — Orally administered over-the-counter (OTC) cough and cold medications contain a variety of active ingredients including acetaminophen, antihistamines, dextromethorphan, decongestants (eg, alpha adrenergic agonists such as phenylephrine or pseudoephedrine), and ethanol. These medications frequently cause significant toxicity in children younger than six years of age.

Topical agents, such as imidazoline ophthalmic and nasal drops (eg, tetrahydrozoline or oxymetazoline), and camphor containing products are also frequently used to control cough and cold symptoms and can have major toxicity.

The approach to pediatric poisoning from OTC cough and cold medication in children will be reviewed here. The toxicity to children posed by individual ingredients (eg, acetaminophen, dextromethorphan, imidazolines, or camphor) and the use of cough and cold medications in children are discussed separately:

●(See "Clinical manifestations and diagnosis of acetaminophen (paracetamol) poisoning in children and adolescents" and "Acetaminophen (paracetamol) poisoning: Management in adults and children".)

●(See "Anticholinergic poisoning".)

●(See "Dextromethorphan misuse and poisoning: Clinical features and diagnosis" and "Dextromethorphan poisoning: Management" and "Opioid intoxication in children and adolescents".)

●(See "Ethanol intoxication in children: Epidemiology, estimation of toxicity, and toxic effects" and "Ethanol intoxication in children: Clinical features, evaluation, and management".)

●(See "Clonidine, xylazine, and related imidazoline poisoning".)

●(See "Phenylephrine and related decongestants: Pediatric poisoning".)

●(See "The common cold in children: Management and prevention", section on 'Over-the-counter medications'.)

EPIDEMIOLOGY — OTC cough and cold medicines are among the most commonly used medications. Several agencies, including the United States Food and Drug Administration (FDA), the Medicine and Healthcare Products Regulatory Agency (MHRA) of the United Kingdom and Health Canada, and the American Academy of Pediatrics recommend against the use of these products in children, although age limits vary [1-3]. Prior to voluntary withdrawals of infant cold medicines, approximately 10 percent of children living in the United States had used a cough and cold medication in any given week [4]. OTC cough and cold medications are also widely used for pediatric upper respiratory infections throughout the world despite lack of proven efficacy [5]. (See "The common cold in children: Management and prevention", section on 'Over-the-counter medications'.)

There are approximately 30,000 pediatric (<20 years) exposures to cold and cold preparations reported to United States regional poison centers annually, with about 55 percent of these occurring in children less than six years of age [6]. Approximately 25 percent of these ingestions cause moderate or major effects; fatalities in infants and children have been reported but are rare, occurring in <1 percent of exploratory ingestions, and, in infants, have only been described after exposures to supratherapeutic doses [1,7-10]. Children under 2 years of age accounted for 70 to 74 percent of deaths in several studies, with child maltreatment an important concern; thus, consultation with social work is strongly advised in these cases [8,11]. In addition, cough and cold medications that contain dextromethorphan are commonly used recreationally by youth and adults. (See "Dextromethorphan misuse and poisoning: Clinical features and diagnosis", section on 'Epidemiology'.)

FORMULATIONS — OTC formulations for the treatment of cough and cold symptoms may be intended for oral or topical use. The exact constituents vary significantly between manufacturers, with hundreds of products widely available worldwide.

Oral agents — OTC cough and cold preparations for oral administration include liquid and solid formulations (eg, pills, tablets, or capsules). Active ingredients, doses, and duration of action vary depending upon the manufacturer (table 1) and commonly consist of one or more of the following agents [12]:

●Antihistamines (eg, chlorpheniramine, brompheniramine, doxylamine, or diphenhydramine)

●Alpha₁ adrenergic decongestants (eg, phenylephrine, pseudoephedrine, or, outside of the United States, phenylpropanolamine)

●Antipyretic and analgesics (eg, acetaminophen or ibuprofen)

●Cough suppressant (typically dextromethorphan)

●Expectorant (eg, guaifenesin)

●Ethanol (adult formulations)

Topical agents — OTC topical formulations typically consist of single agents that vary according to indication as follows:

●Nose drops for congestion – Imidazolines (eg, oxymetazoline, tetrahydrozoline, or naphazoline) or alpha₁ adrenergic agents (eg, phenylephrine)

●Eye drops for redness – Imidazolines (eg, oxymetazoline, tetrahydrozoline or naphazoline)

●Skin rubs and aerosols for cough – Camphor

Rationale for avoidance in children — In randomized trials, systematic reviews, and meta-analyses, orally administered OTC medications have not been proven to work any better than placebo in children and may have serious side effects (table 2). Avoidance of OTC cough and cold medications in children is based upon the following evidence:

●OTC cough and cold medications have been associated with fatal overdose in children younger than two years of age.

●OTC medications have the potential for enhanced toxicity in young children because metabolism, clearance, and drug effects may vary according to age.

●Safe dosing recommendations have not been established for children.

Thus, OTC medications are not recommended for the common cold in children younger than 6 years of age and many experts suggest not using them for children 6 to 12 years of age. (See "The common cold in children: Management and prevention", section on 'Over-the-counter medications'.)

APPROACH — The approach to ingestion of over the counter cough and cold medications depends upon the presence of symptoms, the ingredients of the formulation, and the dose ingested.

Asymptomatic — Many young children with exploratory ingestions of OTC cough and cold medications are asymptomatic at presentation. Proper assessment and management requires the following actions:

●Identify the exact preparation and ingredients of the ingested medication – Even though the patient is asymptomatic, serious overdose with potential toxicity may still occur, especially following ingestions of camphor, tetrahydrozoline and other imidazolines, acetaminophen, dextromethorphan, or sustained release products (table 1). If possible, the clinician should obtain the container with the listed ingredients rather than relying upon the reported brand name because many different cough and cold preparations have very similar names.

If the container cannot be obtained, consultation with a regional poison control center may be helpful to determine the range of possible toxicity based upon the brand name. (See 'Regional poison control centers' below.)

●Determine the ingested dose, need for measurement of an acetaminophen level, and observation – For formulations containing acetaminophen, referral to an emergency department and determination of serum acetaminophen concentration at least four hours after ingestion are indicated for the following patients:

•Larger ingestions in asymptomatic children:

-Acute ingestion >200 mg/kg

-Chronic ingestion ≥200 mg/kg of acetaminophen over a single 24-hour period, >150 mg/kg/day over 48 hours, or >100 mg/kg/day over 72 hours

•Acute or chronic acetaminophen ingestions of an unknown amount

•Unknown cough and cold preparation ingested

•Ingestions with suicidal intent

If obtained, the level should be plotted on the nomogram (figure 1). Depending upon other ingredients and whether they are extended release, several hours of observation with frequent assessment of vital signs after ingestion may be needed to identify delayed toxicity. (See "Clinical manifestations and diagnosis of acetaminophen (paracetamol) poisoning in children and adolescents", section on 'Acute overdoses' and "Clinical manifestations and diagnosis of acetaminophen (paracetamol) poisoning in children and adolescents", section on 'Repeated supratherapeutic ingestion'.)

Most ingestions that are less than the total daily dose of the preparation will not result in toxicity. Frequently, regional poison control centers recommend observing children with these low dose exposures at home. Acute ingestions of acetaminophen of <200 mg/kg in children do not need serum acetaminophen levels and can be observed at home if nontoxic amounts of other ingredients in the cough and cold preparation were ingested.

●Provide activated charcoal in selected patients – For asymptomatic children who have ingested a potentially toxic dose of OTC cough and cold preparations, other than products that contain camphor or imidazolines (eg, tetrahydrozoline), and who present within one hour of ingestion, we recommend a single dose of activated charcoal (AC). The greatest benefit occurs if AC is given within one hour. Administration of AC more than one hour after ingestion in asymptomatic children may also be appropriate if a toxic dose of acetaminophen has been taken. (See "Acetaminophen (paracetamol) poisoning: Management in adults and children", section on 'Gastrointestinal decontamination'.)

Because camphor and imidazolines are rapidly absorbed and have the potential for causing sudden altered mental status (camphor and imidazolines) and seizures (camphor) soon after ingestion, AC administration after isolated camphor or imidazoline exposures is contraindicated [13]. If other agents that bind AC have been ingested, then consultation with a regional poison control center is advised to determine if the benefit of AC administration outweighs the risks. (See "Camphor poisoning in children", section on 'Decontamination' and 'Additional resources' below.)

The recommendation of AC administration following overdose of oral OTC cough and cold medicine preparations derives from indirect evidence of benefit in volunteers, animal studies, and evidence of benefit following ingestions of other medications. Because of adverse effects, such as vomiting and dehydration, the combination of a cathartic (eg, sorbitol) and AC should be used sparingly, if at all, and only a single dose of a cathartic should be given to any patient. (See "Gastrointestinal decontamination of the poisoned patient", section on 'Evidence of efficacy and adverse effects' and "Gastrointestinal decontamination of the poisoned patient", section on 'Cathartics'.)

Symptomatic — The clinician should make every effort to identify the exact formulation and the amount ingested, preferably by obtaining the container with the listed ingredients. Consultation with a regional poison control center is encouraged for all symptomatic overdoses. (See 'Regional poison control centers' below.)

Children and adolescents with symptomatic ingestions of orally administered OTC cough and cold preparations frequently have altered mental status (lethargy, coma, or agitation) and depending upon the ingredients ingested, may develop respiratory depression, severe hypertension, or seizures.

Initial management consists of timely supportive care as follows:

●Initiate continuous cardiorespiratory and pulse oximetry monitoring

●Provide oxygen and support the airway and breathing as needed (see "Pediatric advanced life support (PALS)", section on 'Respiratory distress and failure')

●Measure a rapid blood glucose in patients with altered mental status or seizures and treat hypoglycemia as needed (table 3)

●Obtain intravenous access and blood for a serum acetaminophen level and other studies based upon likely ingestants (see 'Toxicity by ingredient' below)

●Obtain a 12-lead electrocardiogram to identify arrhythmias and signs of drug effect (eg, prolonged QRS or QTc intervals after ingestion of diphenhydramine) (see 'Antihistamines' below)

●Treat severe agitation and elevated blood pressure with intravenous benzodiazepines (eg, lorazepam)

●Treat elevated blood pressure (figure 2A-B and table 4 and table 5) complicated by seizures, pulmonary edema, myocardial ischemia, or vision changes with phentolamine (0.1 mg/kg, maximum dose 5 mg) or a direct-acting antihypertensive agent (eg, sodium nitroprusside) (see "Phenylephrine and related decongestants: Pediatric poisoning", section on 'Hypertensive emergency')

●Manage toxin-induced seizures as shown in the table (table 6)

●For patients with respiratory depression and coma, provide a trial of naloxone in patients, especially in young children who have ingested dextromethorphan or imidazolines (eg, tetrahydrozoline) (see "Opioid intoxication in children and adolescents", section on 'Naloxone' and "Clonidine, xylazine, and related imidazoline poisoning", section on 'Coma with respiratory depression')

●Additional management, including gastrointestinal decontamination, is determined by the specific agents ingested (see 'Toxicity by ingredient' below)

In some patients, poisoning from OTC cough and cold preparations can have a mixed presentation. As an example, toxicity from a formulation that contains antihistamines and decongestants may present with lethargy, bradycardia, and hypertension [14].

Disposition — The clinician can discharge asymptomatic patients who ingested an OTC cough and cold preparation if the following conditions are met:

●Asymptomatic at four to six hours after exposure and a sustained release product has not been ingested

●No evidence of suicidal intent

●A nontoxic acetaminophen level obtained at least four hours after acute ingestion in the following circumstances:

•Ingested dose >200 mg/kg

•Unknown amount of acetaminophen consumed

•Unknown cough and cold preparation ingested

Patients with chronic supratherapeutic dosing of acetaminophen over more than 24 hours warrant additional evaluation as discussed separately. (See "Clinical manifestations and diagnosis of acetaminophen (paracetamol) poisoning in children and adolescents", section on 'Repeated supratherapeutic ingestion'.)

Asymptomatic patients who are suicidal require psychiatric evaluation prior to discharge and should also be carefully evaluated for co-ingestions, including the measurement of an acetaminophen level.

Asymptomatic patients who ingested sustained release alpha₁ adrenergic decongestants (phenylephrine, pseudoephedrine, or phenylpropanolamine [not available in the United States]) warrant observation and frequent measurement of blood pressure for six hours to monitor for delayed hypertension. (See "Phenylephrine and related decongestants: Pediatric poisoning", section on 'Asymptomatic'.)

Persistently symptomatic patients warrant hospital admission.

Intensive care admission is appropriate for patients with the following toxicity:

●Complicated courses marked by severe hypertension, seizures, apnea, or coma

●Central anticholinergic syndrome

●Serotonin syndrome

TOXICITY BY INGREDIENT

Acetaminophen — Many combination OTC cough and cold medications contain acetaminophen and the possibility of significant acetaminophen poisoning caused by acute or repeated supratherapeutic ingestions of these formulations should not be overlooked. Rapid identification of acute acetaminophen overdose is essential because the antidote, acetylcysteine, is most effective when given within eight to 10 hours of an acute acetaminophen ingestion. (See "Acetaminophen (paracetamol) poisoning: Management in adults and children", section on 'Acetylcysteine administration and monitoring'.)

The diagnostic approach to acetaminophen poisoning varies by the type of exposure:

●Acute – Most patients with serious acetaminophen exposure from an acute OTC cough and cold preparation overdose will be symptomatic from other ingredients (eg, antihistamines, decongestants, or dextromethorphan) (table 1). In these patients, a serum acetaminophen concentration should be measured between 4 and 24 hours after an acute overdose and plotted on the acetaminophen nomogram to determine the need for antidotal therapy with acetylcysteine (figure 1). Gastrointestinal decontamination with activated charcoal may be beneficial for several hours after acetaminophen ingestion in selected patients. The diagnosis and treatment of acute acetaminophen poisoning in children is discussed in more detail separately. (See "Clinical manifestations and diagnosis of acetaminophen (paracetamol) poisoning in children and adolescents", section on 'Acetaminophen concentration' and "Acetaminophen (paracetamol) poisoning: Management in adults and children", section on 'Patient with reliable history and acute ingestion'.)

●Chronic – Diagnosis of chronic acetaminophen intoxication (repeated excessive dosing) from multiple supratherapeutic doses of an OTC cough and cold medication is often difficult and requires the combination of astute history-taking and recognition of typical clinical and laboratory abnormalities. Clinicians must specifically ask about the dose and frequency of administration since patients and caregivers may not include OTC cough and cold medications when asked about potentially toxic drugs. Signs and symptoms are insidious in onset, often nonspecific, and easily confused with alternative diagnoses (eg, viral syndrome for which the preparation is being given). Serum concentrations of acetaminophen in this setting do not correlate with toxicity but help to identify exposure. Supportive laboratory findings include elevation of serum liver enzymes (eg, alanine and aspartate aminotransferase) and total serum bilirubin and a prolonged prothrombin time. Recognition and treatment of chronic acetaminophen overdose in children is discussed in greater detail separately. (See "Clinical manifestations and diagnosis of acetaminophen (paracetamol) poisoning in children and adolescents", section on 'Acetaminophen concentration' and "Acetaminophen (paracetamol) poisoning: Management in adults and children", section on 'Inappropriate therapeutic dosing'.)

Antihistamines — The common antihistamines found in OTC cough and cold formulations have traditionally included first-generation antihistamines such as chlorpheniramine, brompheniramine, doxylamine, and diphenhydramine [14,15]. At lower doses, these agents can cause sedation and mild lethargy through effects on the H₁ histamine receptors.

More recently, second-generation antihistamines such as loratadine, cetirizine, and fexofenadine have become common ingredients in cough syrups. Most children remain asymptomatic, even after large overdoses (over 60 times the maximum recommended therapeutic dose) [16]. Among symptomatic patients, minor drowsiness or restlessness without major toxicity is typical.

With higher doses of first-generation antihistamines, anticholinergic poisoning may occur with typical findings associated with the anticholinergic toxidrome as follows (see "Anticholinergic poisoning", section on 'Clinical features of overdose'):

●Flushed and dry skin

●Hyperthermia

●Dilated pupils and blurry vision

●Agitation, tremor, picking movements, delirium, hallucinations, coma, and, especially in children, seizures

●Urinary retention and absent bowel sounds

A rapid overview of clinical assessment and management of central anticholinergic syndrome is provided in the table (table 7) and discussed separately. (See "Anticholinergic poisoning", section on 'Management'.)

While both peripheral and central symptoms are usually present, anticholinergic toxicity can also present with isolated CNS symptoms of delirium, hallucinations, and agitation. A commonly used mnemonic for anticholinergic toxicity is "hot as a hare, blind as a bat, dry as a bone, red as a beet, and mad as a hatter."

Agitation and delirium caused by anticholinergic poisoning is initially treated with benzodiazepines (lorazepam 0.1 mg/kg; maximum dose: 2 mg). Some experts recommend that patients with anticholinergic poisoning manifesting both peripheral signs (eg, flushing, dry skin, and hyperthermia) and central effects (agitated delirium, seizures) receive physostigmine. However, this recommendation is controversial and consultation with a medical toxicologist or regional poison center is encouraged before physostigmine is given. (See "Anticholinergic poisoning" and 'Additional resources' below.)

In addition to anticholinergic effects, diphenhydramine overdose has rarely been associated with prolongation of the QRS and corrected QT intervals and tachyarrhythmias (eg, supraventricular and ventricular tachycardia) [17,18]. Thus, a 12 lead EKG is warranted to identify such changes when diphenhydramine is ingested. Management of toxin-induced QRS and QTc prolongation are discussed separately. (See "Tricyclic antidepressant poisoning", section on 'Sodium bicarbonate for cardiac toxicity' and "First-generation (typical) antipsychotic medication poisoning", section on 'QT interval prolongation'.)

Dextromethorphan — Dextromethorphan (d-3-methoxy-N-methylmorphinan, DXM) is an OTC cough suppressant that is commonly diverted for illicit recreational use. It shares pharmacological similarities with ketamine and phencyclidine (PCP). Rarely, DXM poisoning is associated with profound coma and, in young children, respiratory depression that is responsive to naloxone.

Following acute overdose dextromethorphan produces several characteristic physical findings that may be variably present depending upon the dose ingested as follows (see "Dextromethorphan misuse and poisoning: Clinical features and diagnosis", section on 'Toxic dose' and "Dextromethorphan misuse and poisoning: Clinical features and diagnosis", section on 'Clinical features'):

●Neurobehavioral changes that include euphoria, hallucinations, inappropriate laughing, psychosis with dissociative features, agitation, and coma

●Tachycardia

●Dilated pupils

●Nystagmus

●Diaphoresis (in the absence of anticholinergic co-ingestion)

●"Zombie-like" ataxic gait

Agitation in association with severe dextromethorphan intoxication may also result in hyperthermia and metabolic acidosis with potential for rhabdomyolysis.

In addition, dextromethorphan may precipitate the serotonin syndrome (altered mental status, seizures, autonomic instability, and/or muscular hypertonicity) in overdose and when combined with monoamine oxidase inhibitors, serotonin specific reuptake inhibitors, linezolid, meperidine, tramadol, and other serotonergic agents. Serotonin syndrome is a life-threatening condition. Recognition, differential diagnosis, and treatment are provided in the rapid overview (table 8) and discussed in detail separately. (See "Serotonin syndrome (serotonin toxicity)", section on 'Clinical features' and "Serotonin syndrome (serotonin toxicity)", section on 'Management'.)

The management of dextromethorphan poisoning is discussed in greater detail separately. (See "Dextromethorphan poisoning: Management".)

Ethanol — Although most pediatric cough and cold formulations do not contain ethanol, it is a frequent additive to adult OTC cough and cold preparations. Given the concentration of ethanol in most preparations, significant inebriation is unlikely in older patients, but infants and younger children are at risk for hypoglycemia. (See "Ethanol intoxication in children: Epidemiology, estimation of toxicity, and toxic effects", section on 'Toxic dose' and "Ethanol intoxication in children: Epidemiology, estimation of toxicity, and toxic effects", section on 'Ethanol-induced hypoglycemia'.)

A rapid overview of clinical assessment and emergent management of ethanol overdose is provided in the table (table 9) and discussed separately. (See "Ethanol intoxication in children: Clinical features, evaluation, and management", section on 'Management'.)

Phenylephrine and similar decongestants — Phenylephrine, pseudoephedrine, and phenylpropanolamine (not available in the United States) are substituted phenethylamines and structurally similar to amphetamine and methamphetamine.

Overdose of decongestants typically produces sympathomimetic findings as follows (see "Phenylephrine and related decongestants: Pediatric poisoning", section on 'Clinical features and diagnosis'):

●Hypertension, which may be severe and associated with seizures, altered mental status, heart failure, or kidney damage

●Tachycardia or reflex bradycardia

●Mydriasis

●Diaphoresis

●Agitation

Reflex bradycardia is more likely to occur following exposure to selective alpha₁ adrenergic agonists (eg, phenylephrine or phenylpropanolamine).

Serious complications can occur after decongestant overdose including seizures, rhabdomyolysis, cardiac dysrhythmias, myocardial infarction, cerebral vascular accident, bowel infarction, and death. The risk of complications is largely determined by the severity of hypertension.

The management of phenylephrine overdose is discussed in detail separately. (See "Phenylephrine and related decongestants: Pediatric poisoning", section on 'Management'.)

Tetrahydrozoline and similar imidazolines — A rapid overview provides the approach to recognition and treatment of imidazoline poisoning (table 10). Naloxone has successfully reversed toxicity in case reports of tetrahydrozoline overdose. (See "Clonidine, xylazine, and related imidazoline poisoning", section on 'Coma with respiratory depression'.)

Imidazolines (eg, oxymetazoline, tetrahydrozoline, and naphazoline) are alpha₂ adrenergic agonists that are structurally similar to clonidine and are available in topical nasal decongestants and eye drops. Their therapeutic action is through local vasoconstriction in the nasal passages or the eyes via alpha₂ adrenergic activation.

While systemic toxicity is uncommon after topical application, these agents can produce significant toxicity if taken orally. Clinical findings include lethargy, coma, apnea, bradycardia, hypotension, and hypothermia similar to clonidine ingestion. (See "Clonidine, xylazine, and related imidazoline poisoning".)

Camphor — Camphor, a terpenoid hydrocarbon, is marketed for topical use for cough and nasal decongestion and formulations may combine it with menthol (eg, Vick's vaporub).

Key findings of camphor poisoning include:

●History of oral ingestion or topical exposure to a camphor-containing product

●Seizures which may be the first sign of exposure

●Strong medicinal smell on the breath or if a topical exposure, on the skin

●Oropharyngeal irritation such as burning or stinging

●Nausea, vomiting, and abdominal pain

●Other central nervous system effects, including agitation, confusion, myoclonus, hyperreflexia, lethargy, and/or coma

History of camphor exposure is particularly important because many caregivers may be unaware of the dangers of camphor and not mention its use when seeking medical care.

The management of camphor poisoning in children is discussed in detail separately. (See "Camphor poisoning in children", section on 'Management'.)

PREVENTION — The general prevention of pediatric poisoning is discussed separately. (See "Prevention of poisoning in children".)

Based upon poison control center reports, voluntary withdrawal of cough and cold formulations for children in the United States in 2007 was initially associated with a 33 percent decrease in unintentional exposures to these medications in children younger than 12 years of age and more than a 50 percent decline in ingestions among infants younger than two years of age [19]. However, poisoning from OTC cough and cold medicine remains a persistent problem. Proposed contributing factors include parental misunderstanding of labeling as well as caregivers who are unaware of or are disregarding US Food and Drug Administration (FDA) recommendations [20-22].

Thus, education of caregivers regarding the proper treatment of the common cold in children and reinforcing the avoidance of OTC cough and cold medications in children are additional primary prevention strategies that clinicians may incorporate into their practice. (See "The common cold in children: Management and prevention", section on 'Caregiver education'.)

ADDITIONAL RESOURCES

Regional poison control centers — Regional poison control centers in the United States are available at all times for consultation on patients with known or suspected poisoning, and who may be critically ill, require admission, or have clinical pictures that are unclear (1-800-222-1222). In addition, some hospitals have medical toxicologists available for bedside consultation. Whenever available, these are invaluable resources to help in the diagnosis and management of ingestions or overdoses. Contact information for poison centers around the world is provided separately. (See "Society guideline links: Regional poison control centers".)

Society guideline links — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: General measures for acute poisoning treatment" and "Society guideline links: Treatment of acute poisoning caused by specific agents other than drugs of abuse" and "Society guideline links: Poisoning prevention".)

SUMMARY AND RECOMMENDATIONS

●Formulations – Over-the-counter (OTC) cough and cold preparations for oral administration include liquid and solid formulations (eg, pills, tablets, or capsules). Active ingredients, doses, and duration of action vary depending upon the manufacturer (table 1 and table 2) and frequently include (see 'Formulations' above):

•Acetaminophen

•Antihistamines

•Alpha₁ adrenergic decongestants

•Dextromethorphan

•Ethanol (adult formulations)

OTC topical formulations include (see 'Formulations' above):

•Imidazolines (tetrahydrozoline)

•Phenylephrine

•Camphor

●Approach – The clinician should make every effort to identify the exact formulation and the amount ingested, preferably by obtaining the container with the listed ingredients. Consultation with a regional poison control center is encouraged for all symptomatic overdoses. (See 'Approach' above and 'Additional resources' above.)

●Determine need to measure an acetaminophen concentration – Children who have acutely ingested an OTC cough and cold preparation that contains acetaminophen should have a serum level obtained at least four hours after ingestion and plotted on the nomogram (figure 1) in the following circumstances (see 'Asymptomatic' above):

•Unknown cough and cold preparation ingested

•Patients with suicidal intent

•Acute acetaminophen ingestion >200 mg/kg

•Chronic acetaminophen ingestion ≥200 mg/kg over a single 24-hour period, >150 mg/kg/day over 48 hours, or >100 mg/kg/day over 72 hours

•Acute or chronic acetaminophen ingestion of an unknown amount

●Gastrointestinal decontamination – In an asymptomatic child who has ingested a potentially toxic dose of OTC cough and cold preparations, other than products that contain camphor or imidazolines (eg, tetrahydrozoline), and who presents within one hour of ingestion, we recommend a single dose of activated charcoal (AC) (Grade 1B). The greatest benefit occurs if AC is given within one hour. Administration of AC more than one hour after ingestion in an asymptomatic child may also be appropriate if a toxic dose of acetaminophen has been taken. (See 'Asymptomatic' above.)

Because camphor and imidazolines are rapidly absorbed and have the potential for causing sudden altered mental status (camphor and imidazolines) and seizures (camphor) soon after ingestion, AC administration after isolated camphor or imidazoline exposures is contraindicated.

●Symptomatic patient after ingestion – Children and adolescents with symptomatic ingestions of orally administered OTC cough and cold preparations frequently have altered mental status (lethargy, coma, or agitation) and, depending upon the ingredients ingested, may develop respiratory depression, severe hypertension, or seizures. (See 'Symptomatic' above.)

●Management – Initial management consists of timely supportive care. Additional management, including gastrointestinal decontamination, is determined by the specific agents ingested (see 'Symptomatic' above and 'Toxicity by ingredient' above):

•High doses of antihistamines with anticholinergic syndrome (table 7)

•Dextromethorphan-precipitated serotonin syndrome (table 8)

•Ethanol (table 9)

•Imidazolines (table 10)

●Disposition – The clinician can discharge asymptomatic patients who acutely ingested an OTC cough and cold preparation if the following conditions are met (see 'Disposition' above):

•Asymptomatic at four to six hours after exposure and a sustained release product has not been ingested

•No evidence of suicidal intent

•When indicated, a nontoxic acetaminophen level obtained at least four hours after acute ingestion for preparations containing acetaminophen and when ingredients are unknown

Asymptomatic patients who are suicidal require psychiatric evaluation prior to discharge and should also be carefully evaluated for co-ingestions, including the measurement of an acetaminophen level.