Deconex DMX is a combination of three medications: dextromethorphan (a cough suppressant), guaifenesin (an expectorant), and phenylephrine (a decongestant). It's used for cough and congestion and available over-the-counter as tablets and a liquid.
Loosen phlegm (mucus) in the lungs to make it easier to cough up
Short-term relief of cough and stuffy nose (nasal congestion)
Deconex DMX is a combination of three medications that work together to relieve symptoms caused by throat irritation and the common cold.
Dextromethorphan is a cough suppressant that works in the brain to lower your urge to cough.
Guaifenesin is an expectorant. It thins and loosens mucus that's stuck in your lungs, making it easier to cough it up.
Phenylephrine is a decongestant that clears your sinuses to relieve sinus pressure.
Source: DailyMed
Side effects that you should report to your care team as soon as possible:
Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):
More convenient to take a product that's a combination of three medications
Some liquids are available without sugar for people with diabetes and children
Available over the counter
Available as tablets and liquid
More difficult to customize the dose since Deconex DMX is a combination of three medications
Several brands or manufacturers available with different age cut-offs for children, which raises the risk for accidental overdose
Needs to be taken every 4 to 6 hours
The amount of liquid per dose can be high (up to 20 mL for some brands)
For the liquid forms, use a medication dose cup or a syringe to measure your dose of Deconex DMX. Don't use household spoons because they are not accurate and might cause you to take the wrong dose.
Avoid drinking alcohol while taking Deconex DMX. This raises your risk of sleepiness and dizziness. Don't drive until you know how this medication affects you.
Stop using Deconex DMX and contact your provider if you experience any of the following: 1) nervousness, dizziness, or trouble sleeping; 2) cough or congestion lasting longer than 1 week, keeps coming back, or is present with a fever, rash, or headache; or 3) any other new symptoms that appear. These might be signs of another underlying medical condition.
Don't start any new medications while taking Deconex DMX, especially other cough suppressants, products with guaifenesin, or decongestants, without talking to your provider or pharmacist first. Doing so can raise your risk of overdose and severe side effects, including seizures, hallucinations (seeing things that aren't real), high blood pressure and heart rate, or even death.
Deconex DMX shouldn't be taken with a monoamine oxidase inhibitor (MAOI), such as selegiline, phenelzine (Nardil), or tranylcypromine (Parnate). This combination can raise your risk for severe side effects (e.g., serotonin syndrome, high blood pressure, dizziness). If you're currently taking an MAOI or have taken one in the last 2 weeks, don't use Deconex DMX and contact your provider for other options to treat your symptoms.
Deconex DMX 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.
Risk factors: Taking monoamine oxidase inhibitors (MAOI) 14 days before starting Deconex DMX | Taking other medications that raise serotonin levels in your brain
Serotonin syndrome is a rare, but potentially life-threatening condition where there's too much serotonin in the brain. Serotonin is one of the chemicals in your brain responsible for your mood. Your risk for this condition goes up if you use Deconex DMX with other medications that affect serotonin levels, such as SSRIs (e.g., sertraline (Zoloft)), SNRIs (e.g., duloxetine (Cymbalta)), MAOIs (e.g., phenelzine (Nardil)), lithium, and triptans (e.g., sumatriptan (Imitrex)). Make sure your provider knows about all the medications you take (including over-the-counter medications and supplements) before starting Deconex DMX so they can make sure this medication is safe for you to take. Don't start any new medications while taking Deconex DMX without letting your pharmacist or provider know. Symptoms of serotonin syndrome include fast heart rate, sweating, muscle stiffness or spasms, high fever, and confusion. Seek medical help right away if you have any of these symptoms.
Deconex DMX contains a cough suppressant (dextromethorphan), an expectorant (guaifenesin), and a decongestant (pseudoephedrine), which are all in many other over-the-counter products. Using more than one medication containing a cough suppressant, expectorant, and a decongestant can lead to an accidental overdose and cause serious side effects, including high blood pressure or heart rate, dizziness, seizures, hallucinations (seeing things that aren't real), or even death. Tell your provider or pharmacist about the medications you take before starting Deconex DMX to make sure it's safe for you. Don't start any new medications while taking Deconex DMX without talking to your provider or pharmacist.
To prevent an accidental overdose, read the medication box and package labels carefully. There are several manufacturers that make Deconex DMX, which might have different amounts of the three main ingredients with different age cut-offs for children who can safely use the medication. If you're not sure if a product has any similar ingredients or if the product is safe for your child, ask your pharmacist.
If you or your loved one experiences an accidental overdose, get medical help right away or contact a poison control center at 1-800-222-1222.
Risk factors: Cough from smoking, asthma, or emphysema | Mucus-producing cough | Heart disease or high blood pressure | Thyroid disease | High blood sugar (diabetes) | Urinary problems
Don't take Deconex DMX if you have any of the risk factors listed above unless your provider said it's safe to do so. Taking Deconex DMX can worsen your condition(s) and cause serious side effects. Make sure your provider knows about all medical conditions you have or have had in the past before starting Deconex DMX.
Dosage | Quantity | Price as low as | Price per unit |
---|---|---|---|
15mg/400mg/10mg | 30 tablets | $12.64 | $0.42 |
There are several manufacturers of this medication with different concentrations (amount of Deconex DMX per milliliter (mL) of liquid) and pill strengths. The dose might slightly differ depending on which manufacturer of the medication you have. Be sure to check the medication box for specific instructions.
Below are a few examples of product names with their dosing instructions.
Tablets
Each tablet contains 15 mg of dextromethorphan, 400 mg of guaifenesin, and 10 mg of phenylephrine.
Adults and children age 12 years and older: The typical dose is 1 tablet by mouth every 4 to 6 hours. Don't use more than 4 tablets in a 24-hour period.
Children age 6 years to under 12 years: The typical dose is 1/2 (one-half) tablet by mouth every 4 to 6 hours. Don't use more than 2 tablets in a 24-hour period.
Children under 6 years: Ask your child's provider.
Each tablet contains 17.5 mg of dextromethorphan, 400 mg of guaifenesin, and 10 mg of phenylephrine.
Adults and children age 12 years and older: The typical dose is 1 tablet by mouth every 4 hours. Don't use more than 6 tablets in a 24-hour period.
Children age 6 years to under 12 years: The typical dose is 1/2 (one-half) tablet by mouth every 4 hours. Don't use more than 3 tablets in a 24-hour period.
Children under 6 years: Ask your child's provider.
Liquid
Each 15 mL contains 18 mg of dextromethorphan, 200 mg of guaifenesin, and 10 mg of phenylephrine.
Adults and children age 12 years and older: The typical dose is 1 tablespoonful (15 mL) by mouth every 4 hours. Don't use more than 6 tablespoonfuls (90 mL) in a 24-hour period.
Children age 6 years to under 12 years: The typical dose is 1/2 (one-half) tablespoonful (7.5 mL) by mouth every 4 hours. Don't use more than 3 tablespoonfuls (45 mL) in a 24-hour period.
Children under 6 years: Ask your child's provider.
Robitussin Peak Cold Multi-Symptom Cold:
Each 10 mL contains 20 mg of dextromethorphan, 200 mg of guaifenesin, and 10 mg of phenylephrine.
Adults and children age 12 years and older: The typical dose is 2 teaspoonfuls (10 mL) by mouth every 4 hours. Don't use more than 6 doses (60 mL) in a 24-hour period.
Children under 12 years: Ask your child's provider.
Children's Mucinex Congestion and Cough:
Each 5 mL contains 5 mg of dextromethorphan, 100 mg of guaifenesin, and 2.5 mg of phenylephrine.
Children age 6 years to under 12 years: The typical dose is 2 teaspoonfuls (10 mL) by mouth every 4 hours. Don't use more than 6 doses (60 mL) in a 24-hour period.
Children age 4 years to under 6 years: The typical dose is 1 teaspoonful (5 mL) by mouth every 4 hours. Don't use more than 6 doses (30 mL) in a 24-hour period.
Children under 4 years: Don't use. Ask your child's provider for other options.
Currently take or have taken an MAOI in the last 14 days
Loosen phlegm (mucus) in the lungs to make it easier to cough up
Short-term relief of cough and stuffy nose (nasal congestion)
Short-term relief of coughs caused by minor throat or lung irritation (e.g., common cold)
Loosens and breaks up mucus in the airways (chest congestion)
Chest congestion
Sinus congestion and pressure
Stuffy nose
Cough
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