Westussin DM
Westussin DM is a brand that contains a combination of three medications: dexchlorpheniramine (an antihistamine), dextromethorphan (a cough suppressant), and phenylephrine (a decongestant). It's taken by adults and children to treat allergy and common cold symptoms, like cough, stuffy nose, and watery eyes. Westussin DM is available as an over-the-counter (OTC) liquid solution. The dosage depends on your age, but it's taken by mouth typically every 4 hours as needed. Possible side effects include sleepiness or dizziness.
What is Westussin DM?
What is Westussin DM used for?
Short-term relief of symptoms from allergies and the common cold:
Runny nose
Sneezing
Itchy nose or throat
Itchy, watery eyes
Cough
Stuffy nose (nasal congestion)
How Westussin DM works
Westussin DM is a combination of three medications that work together to relieve symptoms caused by the common cold and allergies.
Dexchlorpheniramine is an antihistamine. It blocks histamine, a natural chemical in your body that causes congestion (stuffy nose), watery eyes, and sneezing.
Dextromethorphan is a cough suppressant. It works in the brain to lower your urge to cough.
Phenylephrine is a decongestant. It works by narrowing the blood vessels in your nose and sinuses to relieve pressure.
Drug Facts
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What are the side effects of Westussin DM?
Common Side Effects
- Sleepiness
- Restlessness
- Dizziness
- Dry mouth
Other Side Effects
- Trouble sleeping
- Trouble urinating
Serious Side Effects
- Serotonin syndrome: fast heart rate, sweating, muscle stiffness or spasms, high fever, confusion
Source:Â DailyMed
Pros and cons of Westussin DM
Pros
Starts to work within 30 minutes to 1 hour
Conveniently combines three medications in one product
Available over the counter as a flavored liquid
Free of sugar, alcohol, dye, and gluten
Cons
Might need to take multiple times a day
People over 65 years old more likely to experience with side effects, like dizziness
Can interact with alcohol
Brand name only
Pharmacist tips for Westussin DM
Use a medication dose cup or an oral syringe to measure your dose of Westussin DM. Don't use household spoons because they aren't accurate and might cause you to take the wrong dose.
The dexchlorpheniramine and dextromethorphan in Westussin DM can make you sleepy or dizzy. This can affect your ability to think or react. Don't drive or do anything that needs a lot of focus until you know how the medication affects you.
If Westussin DM makes you dizzy or sleepy during the day, try only taking this medication at night. Ask your primary care provider about other ways to treat your symptoms during the day that are less likely to cause sleepiness.
While Westussin DM usually makes adults sleepy, it's possible for children who use this medication to become overly excited or energetic. If this happens to your child, speak to your child's pediatrician.
You can use Westussin DM to temporarily relieve cold or allergy symptoms. But let your healthcare team know if your symptoms worsen or last longer than a week. Also tell them if you start to have a fever, rash, or headache. These might be signs that you need more medical attention.
Stop taking Westussin DM and contact your healthcare team if you experience dizziness, nervousness, or trouble sleeping. These might be side effects from certain ingredients in Westussin DM, such as phenylephrine. Depending on how bothersome these side effects are, your care team might recommend taking a lower dose of Westussin DM or using a different option to relieve your symptoms.
Read the ingredients label on all the medications you're taking. Many over-the-counter cold and flu medications contain the same ingredients as those in Westussin DM. Taking more than one antihistamine, cough suppressant, or decongestant at the same time can raise the risk of overdose and severe side effects, such as agitation and trouble breathing.
Don't use Westussin DM if you're currently taking a monoamine oxidase inhibitor (MAOI), such as selegiline or phenelzine (Nardil), or have taken one in the last 14 days. Taking this medication with an MAOI can raise your risk for severe side effects (e.g., serotonin syndrome). Ask a pharmacist for other options to relieve your cough, congestion, and allergy symptoms.
Frequently asked questions about Westussin DM
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What are the risks and warnings for Westussin DM?
Westussin DM can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Sleepiness
Risk factors: Taking Westussin DM with alcohol | Taking other medications that cause drowsiness | 65 years or older
Westussin DM commonly causes drowsiness. This can affect your ability to focus, think, and react. This side effect is more likely to happen or be more intense if you're over 65 years old, drink alcohol while taking this medication, or take other medications that cause drowsiness (e.g., opioids, benzodiazepines, sleep medications). Be careful and avoid activities that require you to be alert, such as driving a car or operating machinery, until you know how this medication affects you.
Serotonin syndrome
Risk factors: Taking monoamine oxidase inhibitors (MAOIs) 14 days before starting Westussin DM | Taking other medications that raise serotonin levels in your brain
The dextromethorphan in Westussin DM can raise your risk for serotonin syndrome. This is a rare, but potentially life-threatening side effect that happens when there's too much serotonin in the brain. Your risk is higher if you're also taking other medications that affect serotonin levels, such as certain antidepressants, MAOIs, and certain migraine medications.
Make sure your healthcare team knows about all the medications you take or plan to take (including over-the-counter medications and supplements) before starting Westussin DM. Get medical help right away if you have any symptoms of serotonin syndrome, such as fast heart rate, sweating, muscle stiffness or spasms, high fever, and confusion.
Accidentally taking too much
Westussin DM contains an antihistamine (dexchlorpheniramine), cough suppressant (dextromethorphan), and a decongestant (phenylephrine). These ingredients can be found in many other over-the-counter products for allergy, cough, and cold.
The risk of accidentally taking too much medication is higher if you use more than one product containing the same or similar ingredients. Tell your primary care provider or pharmacist about the medications you take before starting Westussin DM. And don't start any new medications without talking to them first. Be sure to carefully read the package labels for the active ingredient list and dosing. Ask your pharmacist if you're not sure whether a product has any similar ingredients and whether it's safe for you.
Early signs that you might've accidentally taken too much medication can include confusion, not being aware of your surroundings, flushed or very warm skin, and vision changes. An overdose can lead to serious side effects, such as anxiety or other behavior changes, high blood pressure, and trouble breathing. Get medical help right away or contact a Poison Control Center at 1-800-222-1222 if you or your loved one accidentally took too much medication.
Worsening of medical conditions
Risk factors: Heart disease or high blood pressure | Thyroid problems | High blood sugar (diabetes) | Glaucoma | Mucus-producing cough | Breathing problems (e.g., emphysema, long-term bronchitis) | Urinary conditions
Let your primary care provider and pharmacist know about all the medical conditions you have before you start taking Westussin DM. Ask them whether this medication is safe for you to take.
Westussin DM is generally safe to take, but it might not be the best choice for everyone. If you're 65 years or older, you might experience side effects from the medication more intensely. Additionally, if you have a cough that's lasted for a long time; a cough that occurs with smoking, asthma, or emphysema; or a cough with a lot of mucus, this medication might not be right for you. Westussin DM can also worsen heart disease, high blood pressure, thyroid problems, diabetes, glaucoma, urination problems, or breathing problems. If you have any of these medical conditions, ask your primary care provider if Westussin DM is safe for you.
Westussin DM dosage forms
| Dosage | Quantity | Price as low as | Price per unit |
|---|---|---|---|
| 480ml of 1mg/10mg/5mg/5ml | 1 bottle | $24.93 | $24.93 |
Typical dosing for Westussin DM
Each 5 mL of solution contains 1 mg of dexchlorpheniramine, 10 mg of dextromethorphan, and 5 mg of phenylephrine.
Adults and children 12 years or older: The typical dose is 10 mL by mouth every 4 hours. Don't take more than 6 doses (60 mL) in a 24-hour period.
Children ages 6 years to under 12 years old: The typical dose is 5 mL by mouth every 4 hours. Don't take more than 6 doses (30 mL) in a 24-hour period.
Children under 6 years old: Ask your child's pediatrician.
How much does Westussin DM cost?
Westussin DM contraindications
Currently take or have taken a monoamine oxidase inhibitor (MAOI) in the last 2 weeks
What are alternatives to Westussin DM?
Short-term relief of symptoms from allergies and the common cold:
Runny nose
Sneezing
Itchy nose or throat
Itchy, watery eyes
Cough
Stuffy nose (nasal congestion)
Runny nose
Sneezing
Itchy nose or throat
Itchy, watery eyes
Cough from throat and lung irritation
Stuffy nose (nasal congestion)
Cough from throat and lung irritation
Runny nose
Sneezing
Itchy or watery eyes
Itching of the nose or throat
Stuffy nose (nasal congestion)
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References
Best studies we foundDepartment of Justice/Drug Enforcement Administration. (2020). Narcotics.
Gelotte, C. K., et al. (2015). Pharmacokinetics, safety, and cardiovascular tolerability of phenylephrine HCl 10, 20, and 30 mg after a single oral administration in healthy volunteers. Clinical Drug Investigation.
Oh, S., et al. (2023). Dextromethorphan. StatPearls.
Westminster Pharmaceuticals, LLC. (2024). Westussin DM- dexchlorpheniramine maleate, dextromethorphan hbr, phenylephrine hcl syrup [package insert]. DailyMed.
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