Key takeaways:
Delsym (dextromethorphan) is an over-the-counter (OTC) cough suppressant that can help relieve a dry cough. At recommended doses, it’s generally safe for most adults and children ages 4 and older to take.
A common adult liquid Delsym dosage is 60 mg (10 mL) by mouth every 12 hours as needed. Adults taking monoamine oxidase inhibitors (MAOIs) shouldn’t take Delsym.
Children’s Delsym dosages depend on their age — not body weight. Dosages range from 15 mg (2.5 mL) to 60 mg every 12 hours as needed. Don’t give Delsym to kids younger than age 4.
Delsym is available OTC as a brand-name medication. But you can also find it as a lower-cost generic. If a healthcare professional writes you a prescription for Delsym, GoodRx can help save you money.
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If you’re looking for a medication to help stop an annoying cough, Delsym could be a good choice. Delsym (dextromethorphan) is an over-the-counter (OTC) cough suppressant that can help relieve a dry cough.
Delsym is available OTC for both adults and children. There are also lower-cost generic versions available. But knowing how much Delsym you can take is key in keeping you safe while taking it. Let’s review recommended Delsym dosages for both adults and children.
Note: The Delsym product line includes several cold medications that contain various active ingredients. This article will focus on dosages for Delsym products containing only dextromethorphan.
What’s the typical Delsym (dextromethorphan) dosage for adults?
Delsym is available as both an oral liquid and oral caplets. The liquid can be helpful if you have trouble swallowing pills. Just be sure to use the medicine cup provided by the manufacturer when taking a dose instead of a household spoon. This will help you measure out the right amount of medication.
Delsym oral liquid dosage
Delsym oral liquid contains 30 mg of dextromethorphan in every 5 mL of liquid. This product contains a long-acting version of dextromethorphan. Each dose is designed to last for about 12 hours.
The adult Delsym liquid dosage is 60 mg (10 mL) by mouth every 12 hours as needed. Shake the bottle well before each dose. Don’t take more than 120 mg (20 mL) in 24 hours.
Delsym oral caplets dosage
Each Delsym oral caplet contains 15 mg of dextromethorphan. You may need to take the caplets more frequently than the oral liquid because they’re not long-acting.
The adult Delsym caplet dosage is 30 mg (2 caplets) by mouth every 6 to 8 hours as needed. Don’t take more than 120 mg (8 caplets) in 24 hours.
What’s the typical children’s Delsym dosage?
Children’s Delsym dosages are based on a child’s age. The liquid version is safe to give to most children ages 4 and older. But you shouldn’t give the oral caplets to kids under age 12. Adolescents ages 12 and older can follow the adult Delsym dosages provided above for both the oral liquid and oral caplets.
Only use the dosing spoon, syringe, or measuring cup provided by the manufacturer when giving liquid medication to a child. This ensures your child is getting the correct amount of medication. If you need a replacement dosing device, ask your pharmacist for a new one.
Children’s Delsym liquid dosage
Children’s Delsym contains the same amount of dextromethorphan as the adult version: 30 mg in every 5 mL. Again, be sure to shake the bottle well before each use.
Recommended children’s Delsym dosages are as follows:
Adolescents ages 12 and older: Give 60 mg (10 mL) by mouth every 12 hours as needed. Don’t give more than 120 mg (20 mL) in 24 hours.
Children ages 6 to 11: Give 30 mg (5 mL) by mouth every 12 hours as needed. Don’t give more than 60 mg (10 mL) in 24 hours.
Children ages 4 to 5: Give 15 mg (2.5 mL) every 12 hours as needed. Don’t give more than 30 mg (5 mL) in 24 hours.
Children under age 4: Don’t give Delsym to this age group.
Are Delsym dosages based on body weight?
No, Delsym dosages are not based on body weight. You may see weight-based children’s Delsym doses online if you search for them. But you shouldn’t follow these instructions unless a healthcare professional tells you to do so. Delsym’s manufacturer recommends using a child’s age to determine the safest dosage.
The weight-based children’s Delsym doses found online are often based on a small study from 2004. It looked at the average amount of Delsym that children took in a real-world setting. But this study was not intended as medical advice for parents to follow. It was conducted for observational purposes only.
You should follow the age-based children’s Delsym doses provided by the manufacturer. These are much safer than weight-based dosages. Giving your child a different amount than what’s recommended could end up being too much. And this can lead to harmful side effects (and in severe cases, death) in children.
Are there any dosage adjustments for medical conditions?
Delsym doesn’t typically require any special dosage adjustments. But there are certain situations where it may not be safe to take it. For example, if you have liver problems, Delsym may build up in your body, since it’s broken down by the liver. A healthcare professional may suggest a lower dose of Delsym if you have liver problems.
When should you not take Delsym?
If you take a monoamine oxidase inhibitor (MAOI) such as selegiline (Emsam, Zelapar), you shouldn’t take Delsym. These medications interact with Delsym. This combination can lead to a potentially serious condition called serotonin syndrome. If you’ve recently stopped an MAOI, you should wait at least 2 weeks after your last dose before taking Delsym.
Before starting Delsym, talk to a healthcare professional if you:
Are pregnant or breastfeeding
Have liver problems
Have a chronic cough due to smoking, asthma, or emphysema
Have a productive cough (a cough with mucus)
You should also contact a healthcare professional if your cough lasts longer than 7 days, or goes away and then comes back. If any new symptoms develop while taking Delsym, let a healthcare professional know. These could be signs of a more serious infection.
What happens if you miss a dose of Delsym?
Delsym is usually taken only when you have symptoms. So missed doses shouldn’t be a problem. Just be careful not to take doses too close together. Separate doses by at least 12 hours for Delsym liquid and at least 6 hours for Delsym caplets. Follow the maximum daily dosages listed on the package. Taking more than recommended can lead to side effects, such as nausea and dizziness.
What should you do if you take too much Delsym?
Taking an extra dose of Delsym by accident is unlikely to cause serious harm for most people. But you may experience more side effects than usual. This could include dizziness or drowsiness. So you’d want to be cautious about driving or performing other activities that require alertness.
Dextromethorphan (Delsym’s active ingredient) is also found in many other cough and cold products. Sometimes, it’s necessary to take more than one medication to treat your symptoms. But make sure you read the ingredients on your OTC medicine labels to avoid taking too much dextromethorphan by mistake. It can be easy to take too much without realizing it.
If you believe you’ve taken too much Delsym and are concerned, call a healthcare professional or contact Poison Control at 1-800-222-1222. If you’re having serious side effects, like an irregular heartbeat, call 911 or seek emergency care right away.
Delsym and other products containing dextromethorphan have the potential for misuse. Taking large amounts can create a feeling of being “high.” But it can also cause panic and hallucinations. More serious side effects include seizures, an irregular heart rhythm, and loss of consciousness. Severe cases can even lead to coma or death.
It’s possible to develop dependence to Delsym. If you or someone you know struggles with substance use, help is available. Call the Substance Abuse and Mental Health Services Administration (SAMHSA) National Helpline at 1-800-662-4357 to learn about resources in your area.
How to save on Delsym
There are many ways to save on Delsym, which is available as both a brand-name and generic medication. By having a healthcare professional write a prescription for OTC Delsym, GoodRx can help you save over 50% off the average retail price. The price for generic Delsym at certain pharmacies is as low as $12.80 with a free GoodRx discount.
Frequently asked questions
Yes, it’s possible for Delsym to make you sleepy. But most people don’t experience this side effect. If Delsym makes you sleepy, try to avoid taking it if you need to drive or perform tasks requiring you to be alert. Keep in mind that this side effect may last until the medication starts to wear off (about 12 hours for the liquid and 6 hours for the caplets).
You can typically take plain Delsym and plain Mucinex (guaifenesin) together. But carefully read the OTC labels of the products you’re taking. Mucinex is a brand name for a line of cold medications, some of which may contain dextromethorphan (Delsym’s active ingredient). Similarly, there are Delsym-brand products that may contain guaifenesin, a common ingredient in many Mucinex products.
Delsym doesn’t normally cause diarrhea. But some people may experience other mild digestive side effects, such as nausea or stomach pain. Keep in mind that sometimes Delsym’s inactive ingredients can cause side effects of their own, including diarrhea.
If one Delsym product, such as the liquid, is causing diarrhea, try a different dosage form (such as the caplets). Different dosage forms contain different inactive ingredients. And you may tolerate one better than the other.
Yes, it’s possible for Delsym to make you sleepy. But most people don’t experience this side effect. If Delsym makes you sleepy, try to avoid taking it if you need to drive or perform tasks requiring you to be alert. Keep in mind that this side effect may last until the medication starts to wear off (about 12 hours for the liquid and 6 hours for the caplets).
You can typically take plain Delsym and plain Mucinex (guaifenesin) together. But carefully read the OTC labels of the products you’re taking. Mucinex is a brand name for a line of cold medications, some of which may contain dextromethorphan (Delsym’s active ingredient). Similarly, there are Delsym-brand products that may contain guaifenesin, a common ingredient in many Mucinex products.
Delsym doesn’t normally cause diarrhea. But some people may experience other mild digestive side effects, such as nausea or stomach pain. Keep in mind that sometimes Delsym’s inactive ingredients can cause side effects of their own, including diarrhea.
If one Delsym product, such as the liquid, is causing diarrhea, try a different dosage form (such as the caplets). Different dosage forms contain different inactive ingredients. And you may tolerate one better than the other.
The bottom line
Delsym (dextromethorphan) is a popular over-the-counter (OTC) cough medication. A common adult liquid Delsym dosage is 60 mg (10 mL) every 12 hours as needed. Children’s doses range from 15 mg (2.5 mL) to 60 mg every 12 hours as needed, depending on the child’s age. Don’t give Delsym to children under age 4. Delsym dosages are determined based on a child’s age, not their body weight.
People taking monoamine oxidase inhibitors (MAOIs) should avoid Delsym. Taking too much Delsym can raise the risk of side effects. Seek help right away if you’re experiencing serious side effects.
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References
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