Dextromethorphan

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What is the most important information I should know about dextromethorphan?

Do not give this medication to a child younger than 4 years old. Always ask a doctor before giving a cough or cold medicine to a child. Death can occur from the misuse of cough and cold medicines in very young children.

Do not use dextromethorphan if you have used an MAO inhibitor such as isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam), or tranylcypromine (Parnate) within the past 14 days. Serious, life-threatening side effects can occur if you take dextromethorphan before the MAO inhibitor has cleared from your body.

Do not use any other over-the-counter cough, cold, or allergy medication without first asking your doctor or pharmacist. If you take certain products together you may accidentally take too much of one or more types of medicine. Read the label of any other medicine you are using to see if it contains dextromethorphan.

Dextromethorphan will not treat a cough that is caused by smoking, asthma, or emphysema.

Warning

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

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What is dextromethorphan?

Dextromethorphan is a cough suppressant. It affects the signals in the brain that trigger cough reflex.

Dextromethorphan is used to treat a cough.

Dextromethorphan will not treat a cough that is caused by smoking, asthma, or emphysema.

Dextromethorphan may also be used for other purposes not listed in this medication guide.

Precautions

Ask a doctor or pharmacist about using this medicine if you have emphysema or chronic bronchitis.

This medication may be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

This medication may pass into breast milk and could harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

Artificially-sweetened liquid forms of cough medicine may contain phenylalanine. This would be important to know if you have phenylketonuria (PKU). Check the ingredients and warnings on the medication label if you are concerned about phenylalanine.

Avoid drinking alcohol. It can increase some of the side effects of dextromethorphan.

This medication can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.

Avoid taking diet pills, caffeine pills, or other stimulants (such as ADHD medications) without your doctor’s advice. Taking a stimulant together with cough medicine can increase your risk of unpleasant side effects.

Do not use any other over-the-counter cough, cold, or allergy medication without first asking your doctor or pharmacist. Dextromethorphan is contained in many combination medicines available over the counter. If you take certain products together you may accidentally take too much of this medicine. Read the label of any other medicine you are using to see if it contains dextromethorphan.

Instructions

Seek emergency medical attention if you think you have used too much of this medicine.

Overdose symptoms may include feeling restless or nervous.

Since cough medicine is usually taken only as needed, you may not be on a dosing schedule. If you are taking the medication regularly, take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

Side Effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Stop using dextromethorphan and call your doctor at once if you have any of these serious side effects:

severe dizziness, anxiety, restless feeling, or nervousness;
confusion, hallucinations; or
slow, shallow breathing.

Less serious side effects are more likely, such as stomach upset.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Interactions

Before taking dextromethorphan, tell your doctor if you are using any of the following drugs:

celecoxib (Celebrex);
cinacalcet (Sensipar);
darifenacin (Enablex);
imatinib (Gleevec);
quinidine (Quinaglute, Quinidex);
ranolazine (Ranexa)
ritonavir (Norvir);
sibutramine (Meridia);
terbinafine (Lamisil);
medicines to treat high blood pressure; or
antidepressant medications such as amitriptyline (Elavil, Etrafon), bupropion (Wellbutrin, Zyban), fluoxetine (Prozac, Sarafem), fluvoxamine (Luvox), imipramine (Janimine, Tofranil), paroxetine (Paxil), sertraline (Zoloft), and others.

This list is not complete and there may be other drugs that can interact with dextromethorphan. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Disclaimer

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.