Nuedexta

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Diarrhea, dizziness, cough, vomiting, weakness, or swelling in the hands/ankles/feet may occur. Rarely, slight drowsiness may also occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: easy bruising/bleeding, dark urine, muscle spasms, signs of infection (such as sore throat that doesn't go away, fever, chills), stomach/abdominal pain, yellowing eyes/skin, lupus-like symptoms (joint/muscle pain, chest pain).

Get medical help right away if you have any very serious side effects, including: fainting, fast/irregular heartbeat, severe dizziness.

This medication may increase serotonin and rarely cause a very serious condition called serotonin syndrome/toxicity. The risk increases if you are also taking other drugs that increase serotonin, so tell your doctor or pharmacist of all the drugs you take (see Drug Interactions section). Get medical help right away if you develop some of the following symptoms: fast heartbeat, hallucinations, loss of coordination, severe nausea/vomiting/diarrhea, twitching muscles, unexplained fever, unusual agitation/restlessness.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at MedWatch: The FDA Safety Information and Adverse Event Reporting Program.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Take this medication by mouth with or without food with a full glass of water (8 ounces/240 milliliters) as directed by your doctor, usually one capsule every 12 hours. Do not lie down for at least 10 minutes after taking this medication. To reduce your risk of side effects, your doctor may direct you to start this medication at a low dose (usually one capsule daily for 7 days) and gradually increase your dose. Follow your doctor's instructions carefully.

Avoid eating grapefruit or drinking grapefruit juice while using this medication unless your doctor or pharmacist says you may do so safely. Grapefruit can increase the chance of side effects with this medicine. Ask your doctor or pharmacist for more details.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time(s) each day.

Tell your doctor if your condition does not get better or if it gets worse.

Before taking this medication, tell your doctor or pharmacist if you are allergic to dextromethorphan, quinidine, quinine, or mefloquine; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of: blood/bone marrow disorder (such as low platelets/white blood cells/red blood cells), a certain enzyme deficiency (G6PD deficiency), kidney disease, liver disease, lupus-like syndrome, myasthenia gravis.

Quinidine may cause a condition that affects the heart rhythm (QT prolongation). QT prolongation can rarely cause serious (rarely fatal) fast/irregular heartbeat and other symptoms (such as severe dizziness, fainting) that need medical attention right away.

The risk of QT prolongation may be increased if you have certain medical conditions or are taking other drugs that may cause QT prolongation. Before using quinidine, tell your doctor or pharmacist of all the drugs you take and if you have any of the following conditions: certain heart problems (heart failure, slow heartbeat, QT prolongation in the EKG), family history of certain heart problems (QT prolongation in the EKG, sudden cardiac death).

Low levels of potassium or magnesium in the blood may also increase your risk of QT prolongation. This risk may increase if you use certain drugs (such as diuretics/"water pills") or if you have conditions such as severe sweating, diarrhea, or vomiting. Talk to your doctor about using quinidine safely.

This drug may make you dizzy. Alcohol or marijuana (cannabis) can make you more dizzy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be more sensitive to the side effects of this drug, especially dizziness and QT prolongation (see above). Dizziness can increase the risk of falling.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

Quinidine passes into breast milk. It is unknown if dextromethorphan passes into breast milk. Consult your doctor before breastfeeding.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669. Symptoms of overdose may include: severe dizziness, fainting, fast/irregular heartbeat.

See also the How to Use section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

Some products that may interact with this drug include: fingolimod, propafenone, rolapitant.

This medication can slow down the removal of other medications from your body, which may affect how they work. Examples of affected drugs include aliskiren, codeine, digoxin, mefloquine, tricyclic antidepressants (such as desipramine, imipramine), among others.

Other medications can affect the removal of quinidine from your body, which may affect how quinidine works. Examples include cobicistat, mifepristone, ritonavir, certain azole antifungals (including fluconazole, itraconazole, ketoconazole, posaconazole, voriconazole), certain protease inhibitors (such as nelfinavir, tipranavir), among others.

Taking MAO inhibitors with this medication may cause a serious (possibly fatal) drug interaction. Avoid taking MAO inhibitors (isocarboxazid, linezolid, metaxalone, methylene blue, moclobemide, phenelzine, procarbazine, rasagiline, safinamide, selegiline, tranylcypromine) during treatment with this medication. Most MAO inhibitors should also not be taken for two weeks before and after treatment with this medication. Ask your doctor when to start or stop taking this medication.

Many drugs besides quinidine may affect the heart rhythm (QT prolongation), including artemether/lumefantrine, ranolazine, toremifene, antiarrhythmic drugs (such as amiodarone, disopyramide, dofetilide, dronedarone, ibutilide, sotalol), antipsychotics (such as pimozide, thioridazine, ziprasidone), among others.

The risk of serotonin syndrome/toxicity increases if you are also taking other drugs that increase serotonin. Examples include street drugs such as MDMA/"ecstasy," St. John's wort, certain antidepressants (including SSRIs such as fluoxetine/paroxetine, SNRIs such as duloxetine/venlafaxine), among others. The risk of serotonin syndrome/toxicity may be more likely when you start or increase the dose of these drugs.

Quinidine is very similar to quinine. Do not use medications containing quinine while using quinidine.