- Side Effects
- Drug Interactions
- Pregnancy & Breastfeeding
- What Else to Know
Generic Name: acetaminophen/doxylamine/dextromethorphan/phenylephrine
Brand Names: Alka-Seltzer Plus Night Cold Formula, Tylenol Cold Multi-Symptom Nighttime Liquid, Alka-Seltzer Plus Night Severe Cold, Cough and Flu, Alka-Seltzer Plus Night Sinus Congestion, Allergy and Cough
Drug Class: Cough/Cold, Non-narcotic Combos; Analgesic/Antihistamine/Antitussive/Decongestant Combos
What is acetaminophen, doxylamine, dextromethorphan, and phenylephrine, and what is it used for?
Acetaminophen/doxylamine/dextromethorphan/phenylephrine is a combination medication used for the temporary relief of common cold and flu symptoms, including fever, headache, body aches, cough, sore throat, runny nose, sneezing, and nasal and sinus congestion. Four drugs are combined in specific dosages in the formulation and the combo drug is available over the counter (OTC). Each medication works in a different way and together they provide more effective relief than any of them as a single agent.
- Acetaminophen is an analgesic and antipyretic drug used to relieve pain and fever. Acetaminophen relieves pain by blocking pain impulse generation and inhibiting the synthesis of prostaglandin in the central nervous system (CNS). Prostaglandin is a natural substance in the body that initiates inflammation. Acetaminophen reduces fever by acting on the hypothalamus region of the brain which regulates temperature.
- Doxylamine is an antihistamine that works by blocking the activity of histamine, a natural compound in the body that causes allergy symptoms. Doxylamine binds non-selectively to all H1 receptors, including in the central and peripheral nervous systems, uterus, gastrointestinal tract, large blood vessels and bronchial muscles. Doxylamine produces sedation, reduces nausea and vomiting, and relieves upper respiratory tract allergy symptoms.
- Dextromethorphan suppresses cough by reducing the sensitivity of cough receptors in the brain region that stimulate the cough reflex and preventing the transmission of cough impulses.
- Phenylephrine belongs to a class of medications known as alpha1 agonists. Phenylephrine stimulates alpha1 adrenergic receptors, protein molecules located in smooth muscle tissues around blood vessels, making the muscles contract. This constricts the blood vessels in the nasal and sinus passages, reducing congestion.
- Do not use in patients with known hypersensitivity to acetaminophen, doxylamine, dextromethorphan, phenylephrine or any other component of the formulation.
- Do not use acetaminophen/doxylamine/dextromethorphan/phenylephrine in patients with any of the following conditions:
- Severe impairment of liver function
- Narrow-angle glaucoma, a condition with high intraocular pressure that damages the optic nerve
- Prostate enlargement and urinary obstruction
- Bladder neck obstruction
- Stenosing peptic ulcer
- G6PD enzyme deficiency, a genetic disorder
- Do not use acetaminophen/doxylamine/dextromethorphan/phenylephrine in children below 12 years of age or for pediatric sedation.
- Do not use concurrently with any other drug containing acetaminophen.
- Do not use concurrently or within 14 days after treatment with monoamine oxidase inhibitor (MAOI) type of antidepressant medications.
- Dextromethorphan may slow the respiratory rate, use with caution.
- Doxylamine may cause drowsiness and impair mental and physical abilities. Caution patients appropriately.
- Use acetaminophen/doxylamine/dextromethorphan/phenylephrine with caution in patients with:
- Cardiovascular diseases including hypertension and ischemic heart disease
- Diabetes mellitus
- Respiratory disease
- Thyroid dysfunction
- Use with caution in patients with alcoholic liver disease. Drinking 3 or more alcoholic drinks a day can increase the risk of liver damage. Advise patients to avoid drinking or limit to less than 3 drinks a day.
- Use with caution in elderly or debilitated patients.
- There have been rare reports of life-threatening skin reactions including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and acute generalized exanthematous pustulosis (AGEP) with symptoms such as blisters, rash and redness. Discontinue the drug if such symptoms develop.
What are the side effects of acetaminophen, doxylamine, dextromethorphan, and phenylephrine?
Common side effects of acetaminophen/doxylamine/dextromethorphan/phenylephrine include:
- Constriction of peripheral and abdominal blood vessels
- High blood pressure (hypertension)
- Reflex increase in heart rate (reflex tachycardia)
- Gastrointestinal disturbances
- Dry nose, mouth and throat
- Thickening of the mucus in nose and throat
- Increase in bilirubin and alkaline phosphatase
- Blood disorders including:
- Low red blood cell count (anemia)
- Low count of neutrophil immune cells (neutropenia)
- Low count of leukocyte immune cells (leukopenia)
- Low count of all types of blood cells (pancytopenia)
- Skin rash
Call your doctor immediately if you experience any of the following symptoms or serious side effects while using this drug:
- Serious heart symptoms include fast or pounding heartbeats, fluttering in your chest, shortness of breath, and sudden dizziness;
- Severe headache, confusion, slurred speech, severe weakness, vomiting, loss of coordination, feeling unsteady;
- Severe nervous system reaction with very stiff muscles, high fever, sweating, confusion, fast or uneven heartbeats, tremors, and feeling like you might pass out; or
- Serious eye symptoms include blurred vision, tunnel vision, eye pain or swelling, or seeing halos around lights.
This is not a complete list of all side effects or adverse reactions that may occur from the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may also report side effects or health problems to the FDA at 1-800-FDA-1088.
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What are the dosages of acetaminophen, doxylamine, dextromethorphan, and phenylephrine?
- 325 mg/6.25 mg/10 mg/5 mg
Adult and pediatric:
Congestion, Rhinorrhea, Cough, Sore Throat, Headache, Fever, Minor Aches and Pains
Children below 12 years
- Ask a pediatrician
Children 12 years and above and adults
- 2 caps orally once every 4 hours as needed; not to exceed 12 caps/day
- Overdose of acetaminophen/doxylamine/dextromethorphan/phenylephrine can cause kidney and liver damage with symptoms that include nausea, vomiting, loss of appetite, sweating, abdominal pain, extreme tiredness, yellowing eyes and skin, dark urine, agitation, confusion, irregular heart rhythm, low blood pressure, high temperature, absence of sweating, urinary retention, seizure, muscle breakdown (rhabdomyolysis), respiratory failure and coma.
- Overdose may be treated with symptomatic and supportive care, including administration of activated charcoal to eliminate undigested drug if it is within one hour of ingestion, and N-acetylcysteine, antidote to acetaminophen.
What drugs interact with acetaminophen, doxylamine, dextromethorphan, and phenylephrine?
Inform your doctor of all medications you are currently taking, who can advise you on any possible drug interactions. Never begin taking, suddenly discontinue, or change the dosage of any medication without your doctor’s recommendation.
- Severe interactions of acetaminophen/doxylamine/dextromethorphan/phenylephrine include:
- iobenguane I 123
- selegiline transdermal
- Acetaminophen/doxylamine/dextromethorphan/phenylephrine has serious interactions with at least 37 different drugs. Acetaminophen/doxylamine/dextromethorphan/phenylephrine has moderate interactions with at least 270 different drugs.
- Acetaminophen/doxylamine/dextromethorphan/phenylephrine has mild interactions with at least 62 different drugs.
The drug interactions listed above are not all of the possible interactions or adverse effects. For more information on drug interactions, visit the RxList Drug Interaction Checker.
It is important to always tell your doctor, pharmacist, or health care provider of all prescription and over-the-counter medications you use, as well as the dosage for each, and keep a list of the information. Check with your doctor or health care provider if you have any questions about the medication.
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Pregnancy and breastfeeding
- Acetaminophen/doxylamine/dextromethorphan/phenylephrine should be used by pregnant women only if clearly needed. The lowest effective dose for the shortest possible time is recommended.
- Acetaminophen/doxylamine/dextromethorphan/phenylephrine is present in breastmilk, use with caution if you are a nursing mother.
- If you are pregnant or breastfeeding, do not take any OTC drug, including acetaminophen/doxylamine/dextromethorphan/phenylephrine, without first checking with your healthcare provider.
What else should I know about acetaminophen, doxylamine, dextromethorphan, and phenylephrine?
- Take acetaminophen/doxylamine/dextromethorphan/phenylephrine exactly as prescribed or as per label instructions if taking OTC medication.
- Do not take higher or more frequent doses, do not exceed daily recommended dosage and do not take for prolonged periods.
- Avoid overdose by checking product labels carefully. Acetaminophen is found in many dosage forms and many combination products.
- Discontinue immediately if you develop hypersensitivity reactions or severe skin reactions.
- Discontinue use and consult with your healthcare provider if:
- Symptoms do not get better within 7 days or are accompanied by fever
- Fever gets worse or lasts longer than 3 days
- You experience any new symptoms, dizziness, nervousness or sleeplessness.
- You have redness or swelling
- Sore throat is severe, lasts longer than two days, or is accompanied by fever, rash, headaches, nausea or vomiting
- Do not take acetaminophen/doxylamine/dextromethorphan/phenylephrine if you have chronic cough associated with smoking, asthma, or emphysema, or if it occurs with heavy phlegm or mucus, unless directed by your physician.
- Avoid or limit intake of alcohol while on treatment.
- Doxylamine in the combination drug can make you drowsy. Avoid hazardous tasks such as driving and operating heavy machinery while under treatment.
- Store safely out of reach of children.
- In case of overdose, seek immediate medical help or contact Poison Control.
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Acetaminophen/doxylamine/dextromethorphan/phenylephrine is a combination medication used for the temporary relief of common cold and flu symptoms, including fever, headache, body aches, cough, sore throat, runny nose, sneezing, and nasal and sinus congestion. Common side effects of acetaminophen, doxylamine, dextromethorphan, and phenylephrine include dizziness, drowsiness, headache, tremor, excitability, restlessness, constriction of peripheral and abdominal blood vessels, high blood pressure (hypertension), reflex increase in heart rate (reflex tachycardia), gastrointestinal disturbances, and others. Consult your doctor if pregnant or breastfeeding.
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The common cold (viral upper respiratory tract infection) is a contagious illness that may be caused by various viruses. Symptoms include a stuffy nose, headache, cough, sore throat, and maybe a fever. Antibiotics have no effect upon the common cold, and there is no evidence that zinc and vitamin C are effective treatments.
Cold and Cough Medicine for Infants and Children
The safety of giving infants and children over-the-counter (OTC) cold and cough medicine is important for caregivers to understand. While there is no "gold standard" recommendation for giving infants and children OTC cold and cough medicine for fever, aches, cough, and runny nose, a few standards have been recommended.
Can You Take Tylenol Cold and Flu While Breastfeeding?
Tylenol is a well-known brand of acetaminophen and it is safe and effective for fever and pain.A void combined products like Tylenol Cold and Flu while you are breastfeeding.
Adenovirus 14 (Killer Cold Virus)
Adenovirus infection, particularly Ad14, or the "killer cold virus" has been on the increase in the past two years. Symptoms range from those experienced with colds, sore throat, bronchitis, pneumonia, diarrhea, pinkeye, fever, bladder infection, and neurological conditions. Diagnosis and treatment options need to be discussed with your physician.
How Do You Get Rid of a Cold Overnight?
Cold symptoms are part of your body’s healing processes. Most of the time, it does not require any help. However, you can get rid of a cold faster, even overnight, by resting, drinking hot fluids, blowing your nose, gargling with salt water, taking a hot shower, using a humidifier and taking OTC pain relievers and decongestants.
How Long Is a Cold or Flu Contagious?
Viruses cause the common cold and the flu. Early symptoms and signs for a cold and the flu are similar, however, flu symptoms are typically more severe than cold symptoms. Cold and flu viruses are transmitted typically via coughing or sneezing.
Common Cold: Early Signs and 4 Stages
The common cold or viral rhinitis is an upper respiratory infection caused by several types of viruses. It is one of the most common infectious diseases affecting humans. A common cold may typically follow a certain pattern of progression that has four different stages.
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Before treating a cold, the flu, or allergies with over-the-counter (OTC) medications, it's important to know what's causing the symptoms, which symptoms one wishes to relieve, and the active ingredients in the OTC product. Taking products that only contain the medications needed for relieving your symptoms prevents ingestion of unnecessary medications and reduces the chances of side effects.
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When you're feeling sick, it can be difficult to distinguish the symptoms of a COVID-19 infection from the symptoms of the common cold or the flu (influenza). While fever is common with the flu and COVID-19, sneezing is typically only associated with colds. Though sore throats are typical with colds, they are uncommon with COVID-19 infections and the flu.
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Though the common cold and flu share many signs and symptoms, they are caused by different viruses. Signs and symptoms include sneezing, sore throat, runny nose, fatigue, and cough. Treatment options for the cold and flu are similar and focus on reducing symptoms. Doctors may prescribe antivirals/neuraminidase inhibitors for the flu.
Is It a Cold or a Sinus Infection?
A sinus infection, also known as sinusitis or rhinosinusitis, is a condition in which the delicate membranes that line the sinuses may get swollen and become red. A cold or common cold is a viral infection. It affects the upper respiratory system, which includes the nose, mouth, throat, and lungs.
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