Dextromethorphan is a generic, over-the-counter (OTC) drug used to help relieve cough. The medication is also available as the brand-name drug Delsym. Dextromethorphan belongs to the antitussive drug class.
The Food and Drug Administration (FDA) has approved dextromethorphan to help with short-term relief of cough caused by minor throat or airway irritation, for example, due to a cold.
Dextromethorphan comes as an oral liquid-filled capsule that’s suitable for adults and children ages 12 years and older. It also comes as an oral extended-release (ER)* liquid suspension that you drink. This form is suitable for adults and children ages 4 years and older.
* ER forms release the medication slowly over time instead of all at once.
Drug details
You’ll find key information about dextromethorphan below.
- Drug class: antitussive (cough suppressant)
- Drug forms: oral liquid-filled capsule and oral ER liquid suspension
- Brand-name version available? yes
- Prescription required? no
- Controlled substance? no
Dextromethorphan is a generic drug. A generic drug is an exact copy of the active ingredient in a brand-name medication. Delsym is the brand-name medication that dextromethorphan suspension is based on. A generic is considered to be as safe and effective as the original drug. Generics tend to cost less than brand-name drugs.
If you’re interested in taking Delsym instead of dextromethorphan, talk with your doctor or pharmacist. To learn more about how generics compare with brand-name drugs, see this article.
Dextromethorphan can cause mild or serious side effects. The following lists contain some of the key side effects that may occur while taking dextromethorphan. These lists do not include all possible side effects.
For more information about the possible side effects of dextromethorphan, talk with your doctor or pharmacist. They can give you tips on how to manage any side effects that may concern or bother you.
Note: The FDA tracks side effects of drugs it has approved. If you’d like to notify the FDA about a side effect you’ve had with dextromethorphan, you can do so through MedWatch.
Mild side effects
Below is a partial list of mild side effects of dextromethorphan. To learn about other mild side effects, talk with your doctor or pharmacist.
Mild side effects of dextromethorphan can include:
- drowsiness
- dizziness
- nausea and vomiting
- abdominal pain
- restlessness
- skin rash
- mild allergic reaction*
Most of these side effects may go away within a few days to a couple of weeks. However, if they become more severe or don’t go away, talk with your doctor or pharmacist.
* For more information about allergic reaction and dextromethorphan, see “Allergic reaction” below.
Serious side effects
Serious side effects from dextromethorphan aren’t common, but they can occur. Call your doctor right away if you have serious side effects. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.
Serious side effects can include severe allergic reaction. For details, see “Allergic reaction” just below.
ALLERGIC REACTIONAs with most drugs, some people can have an allergic reaction after taking dextromethorphan. It’s not known how often this side effect occurs.
Symptoms of a mild allergic reaction can include:
A more severe allergic reaction is rare but possible. Symptoms of a severe allergic reaction can include:
- swelling under your skin, typically in your eyelids, lips, hands, or feet
- swelling of your tongue, mouth, or throat
- trouble breathing
Call your doctor right away if you have an allergic reaction to dextromethorphan, as the reaction could become severe. Call 911 or your local emergency number if your symptoms feel life threatening or if you think you’re having a medical emergency.
The dextromethorphan dosage recommended will depend on several factors. These include:
- the severity of your cough
- your age
- the form of dextromethorphan you take
The following information describes dosages that are commonly used or recommended.
Dosage for cough
Here’s dextromethorphan dosage information for cough in adults. The strength of the dose is given in milligrams (mg) and mg per milliliter (mg/mL).
| Form | oral liquid-filled capsule | oral ER* liquid suspension |
| Strength | 15 mg | 30 mg/5 mL |
| Adult dosage | 2 capsules every 6–8 hours as needed | 10 mL every 12 hours as needed |
| Maximum dosage | 8 capsules in any 24-hour period | 20 mL in any 24-hour period |
* ER dose forms release the medication slowly over time instead of all at once.
Children’s dosage
Here’s dextromethorphan dosage information for cough in children:
| Form | oral liquid-filled capsule | oral ER liquid suspension |
| Strength | 15 mg | 30 mg/5 mL |
| Dosage for children ages 12 years and older | • 2 capsules every 6–8 hours as needed • maximum dosage: 8 capsules in any 24-hour period | • 10 mL every 12 hours as needed • maximum dosage: 20 mL in any 24-hour period |
| Dosage for children ages 6–11 years | not suitable | • 5 mL every 12 hours as needed • maximum dosage: 10 mL in any 24-hour period |
| Dosage for children ages 4–5 years | not suitable | • 2.5 mL every 12 hours as needed • maximum dosage: 5 mL in any 24-hour period |
About taking dextromethorphan
Below you’ll find information about key dosage issues.
- When to take: You can take dextromethorphan capsules every 6–8 hours as needed to help relieve cough. You should take dextromethorphan suspension every 12 hours as needed to help relieve cough. Refer to the tables above for the maximum dosages recommended in any 24-hour period.
- Taking dextromethorphan with food: You can take dextromethorphan with or without food.
- Crushing, splitting, or chewing dextromethorphan: You should not crush, split, or chew dextromethorphan capsules.
- Length of use: Dextromethorphan is meant to be taken for the short-term relief of cough. If your cough lasts longer than 7 days, stop taking dextromethorphan and contact your doctor. For more information about this, see the “Dextromethorphan uses” section below.
Overdose
Taking more than the recommended dosage of dextromethorphan can lead to harmful effects. Do not take more dextromethorphan than recommended on the product label.
Overdose symptoms
Symptoms of an overdose can include:
- sleepiness
- dizziness
- nausea and vomiting
- fast heartbeat
- hallucinations (seeing or hearing things that aren’t real)
- psychosis (loss of touch with reality)
- slow, shallow breathing
- seizures
- serotonin syndrome (a dangerous condition caused by a buildup of serotonin in your body)
- loss of consciousness
What to do in case of overdose
If you think you’ve taken too much of this drug, call your doctor. You can also call America’s Poison Centers at 800-222-1222 or use its online tool. However, if your symptoms are severe, call 911 or your local emergency number, or go to the nearest emergency room right away.
If you can become pregnant, consider the following information about pregnancy, fertility, birth control, and breastfeeding.
Dextromethorphan and pregnancy
It’s not known whether dextromethorphan should be taken during pregnancy. If you’re planning a pregnancy or can become pregnant, talk with your doctor before taking this medication.
Dextromethorphan and birth control
It’s not known whether dextromethorphan is safe to take during pregnancy. If you’re sexually active and you or your partner can become pregnant, talk with your doctor about your birth control needs while you’re taking dextromethorphan.
Dextromethorphan and breastfeeding
It’s not known whether dextromethorphan should be taken while breastfeeding. If you’re currently breastfeeding or planning to do so, talk with your doctor before taking this medication.
Here are answers to some frequently asked questions about dextromethorphan.
Is it safe to take dextromethorphan with guaifenesin or ibuprofen?
Yes, it’s usually safe to take dextromethorphan with guaifenesin (Mucinex) or ibuprofen (Advil, Motrin). In fact, some over-the-counter (OTC) medications contain this combination of drugs to help relieve cough, cold, and flu symptoms. (Dextromethorphan is used to relieve cough in some situations. For details, see “Dextromethorphan uses” below.)
Guaifenesin is a cough expectorant. It helps thin the mucus in your airways, making it easier to cough up. Ibuprofen is a pain reliever that also treats fever.
Before taking dextromethorphan with other OTC cough, cold, or flu medications, be sure to check the ingredients of these products. You should not take dextromethorphan with combination products that also contain dextromethorphan. This could lead to overdose. To learn more, see “Overdose” in the “Dextromethorphan dosage” section above.
Can dextromethorphan be used for depression?
No, dextromethorphan is not prescribed for depression. You should not take OTC dextromethorphan to treat depression.
Doctors sometimes prescribe a brand-name medication called Auvelity to treat depression. Auvelity contains dextromethorphan with another drug called bupropion. These drugs work together to treat depression. The dose of dextromethorphan in Auvelity is different than the recommended dose of OTC dextromethorphan.
To learn more about Auvelity, see this article or talk with your doctor. For more information about dextromethorphan and depression, see this article.
Does dextromethorphan make you feel “high”?
No, not usually. Taking dextromethorphan at recommended doses to help relieve cough shouldn’t make you feel high.
However, misuse of dextromethorphan can make you feel high. (With misuse, a drug is taken in a way that’s not recommended, for example in a higher dosage.) Misuse of dextromethorphan can also cause hallucinations or “tripping” (seeing or hearing things that aren’t real).
Misusing dextromethorphan for these effects can cause harmful side effects, such as breathing problems. To learn more about this, see “Overdose” in the “Dextromethorphan dosage” section above.
You should not take more dextromethorphan than the recommended dosage.
Dextromethorphan can interact with several other medications. It can also interact with certain supplements as well as certain foods.
Before taking dextromethorphan, talk with your doctor and pharmacist. Tell them about all prescription, over-the-counter, and other drugs you take. Also tell them about any vitamins, herbs, and supplements you use. Sharing this information can help you avoid potential interactions.
Interactions with medications, foods, and supplements
Below is a list of medications, supplements, and foods that can interact with dextromethorphan. This list does not contain all drugs that may interact with dextromethorphan. If you have questions about drug interactions that may affect you, ask your doctor or pharmacist.
| Medications that can interact with dextromethorphan | monoamine oxidase inhibitors (MAOIs), such as phenelzine (Nardil), selegiline (Emsam, Zelapar), or tranylcypromine (Parnate) |
Alcohol interaction
If you drink alcohol, it may not be safe to consume while taking dextromethorphan. Alcohol and dextromethorphan can cause some similar side effects, such as drowsiness, dizziness, and nausea. You may have a raised risk of these side effects if you drink alcohol with dextromethorphan.
If you have questions about how much alcohol is safe to drink while taking dextromethorphan, talk with your doctor or pharmacist.
The Food and Drug Administration (FDA) approves over-the-counter (OTC) drugs such as dextromethorphan to treat certain conditions.
Dextromethorphan for cough
Dextromethorphan is approved to temporarily relieve cough caused by minor throat or airway irritation. Dextromethorphan can be used for this purpose in adults and certain children (see just below).
Keep in mind that dextromethorphan doesn’t treat the underlying cause of your cough, such as the common cold or flu.
You should talk with your doctor before taking dextromethorphan if you have a cough that produces a lot of mucus, or an ongoing cough that’s related to smoking, asthma, or chronic obstructive pulmonary disease (COPD).
Dextromethorphan and children
Dextromethorphan is approved to help relieve cough caused by minor throat or airway irritation (see just above for more information).
Dextromethorphan oral liquid-filled capsule is used for children ages 12 years and older.
Dextromethorphan oral ER liquid suspension is used for children ages 4 years and older. (ER dose forms release the medication slowly over time instead of all at once.)
As with all medications, the cost of dextromethorphan oral forms can vary. The actual price you’ll pay depends on your insurance plan, your location, and the pharmacy you use.
Financial and insurance assistance: If you need financial support to pay for dextromethorphan, or if you need help understanding your insurance coverage, help is available.
Other cough medications are available that can relieve your cough. Some may be a better fit for you than others. If you’re interested in finding an alternative to dextromethorphan, talk with your pharmacist. They can tell you about other medications that may work well for you.
The following drugs are alternatives to dextromethorphan:
- dextromethorphan/guaifenesin (Robitussin DM, Mucinex DM)
- guaifenesin (Mucinex)
- dextromethorphan/doxylamine (NyQuil Cough)
- dextromethorphan/promethazine (Promethazine DM)
This drug comes with several precautions.
Dextromethorphan may not be right for you if you have certain medical conditions or other factors affecting your health. Be sure to talk with your doctor or pharmacist if any of the following apply to you:
- liver problems
- cough that produces a lot of mucus
- ongoing cough, such as related to smoking or chronic obstructive pulmonary disease (COPD)
- previous allergic reaction to dextromethorphan or a similar drug
- pregnancy
- breastfeeding
Note: For more information about the potential negative effects of dextromethorphan, see the “Dextromethorphan side effects” section above.
Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.