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Phenylephrine/ diphenhydramine/ dextromethorphan suspension

Generic Name: phenylephrine/diphenhydramine/dextromethorphan (FEN-il-EF-rin/DYE-fen-HYE-dra-meen/DEX-troe-meth-OR-fan)
Brand Name: Duratuss AC 12

Phenylephrine/ diphenhydramine/ dextromethorphan suspension is used for:

Relieving symptoms of sinus congestion, runny nose, sneezing, and cough due to colds, upper respiratory infections, and allergies. It may also be used for other conditions as determined by your doctor.

Phenylephrine/diphenhydramine/dextromethorphan suspension is a decongestant, antihistamine, and cough suppressant combination. It works by constricting blood vessels and reducing swelling in the nasal passages. The antihistamine works by blocking the action of histamine, which helps reduce symptoms such as watery eyes and sneezing. The cough suppressant works in the brain to help decrease the cough reflex to reduce a dry cough.

Do NOT use phenylephrine/ diphenhydramine/ dextromethorphan suspension if:

  • you are allergic to any ingredient in phenylephrine/diphenhydramine/dextromethorphan suspension
  • you have severe high blood pressure, severe heart blood vessel disease, rapid heartbeat, severe heart problems, stomach ulcer, or narrow-angle glaucoma
  • you are unable to urinate or are having an asthma attack
  • you take sodium oxybate (GHB) or you have taken furazolidone or a monoamine oxidase inhibitor (MAOI) (eg, phenelzine) within the last 14 days

Contact your doctor or health care provider right away if any of these apply to you.

Before using phenylephrine/ diphenhydramine/ dextromethorphan suspension:

Some medical conditions may interact with phenylephrine/diphenhydramine/dextromethorphan suspension. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

  • if you are pregnant, planning to become pregnant, or are breast-feeding
  • if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
  • if you have allergies to medicines, foods, or other substances
  • if you have a fast, slow, or irregular heartbeat
  • if you have a history of adrenal gland problems (eg, adrenal gland tumor); heart problems; high blood pressure; diabetes; heart blood vessel problems; stroke; glaucoma; a blockage of your stomach, bladder, or intestines; ulcers; trouble urinating; an enlarged prostate or other prostate problems; seizures; mental or mood problems (eg, depression); or an overactive thyroid
  • if you have a history of asthma, chronic cough, lung problems (eg, chronic bronchitis, emphysema), or chronic obstructive pulmonary disease (COPD), or if your cough occurs with large amounts of mucus
  • if you are in poor health or are very overweight

Some MEDICINES MAY INTERACT with phenylephrine/diphenhydramine/dextromethorphan suspension. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Digoxin or droxidopa because the risk of irregular heartbeat or heart attack may be increased
  • Beta-blockers (eg, propranolol), catechol-O-methyltransferase (COMT) inhibitors (eg, tolcapone), furazolidone, indomethacin, MAOIs (eg, phenelzine), sodium oxybate (GHB), or tricyclic antidepressants (eg, amitriptyline) because they may increase the risk of phenylephrine/diphenhydramine/dextromethorphan suspension's side effects
  • Bromocriptine or hydantoins (eg, phenytoin) because the risk of their side effects may be increased by phenylephrine/diphenhydramine/dextromethorphan suspension
  • Guanadrel, guanethidine, mecamylamine, methyldopa, or reserpine because their effectiveness may be decreased by phenylephrine/diphenhydramine/dextromethorphan suspension

This may not be a complete list of all interactions that may occur. Ask your health care provider if phenylephrine/diphenhydramine/dextromethorphan suspension may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use phenylephrine/ diphenhydramine/ dextromethorphan suspension:

Use phenylephrine/diphenhydramine/dextromethorphan suspension as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take phenylephrine/diphenhydramine/dextromethorphan suspension by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
  • Shake well before each use.
  • Use a measuring device marked for medicine dosing. Ask your pharmacist for help if you are unsure of how to measure your dose.
  • Drink plenty of water while taking phenylephrine/diphenhydramine/dextromethorphan suspension.
  • If you miss a dose of phenylephrine/diphenhydramine/dextromethorphan suspension, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use phenylephrine/diphenhydramine/dextromethorphan suspension.

Important safety information:

  • Phenylephrine/diphenhydramine/dextromethorphan suspension may cause drowsiness, dizziness, or blurred vision. These effects may be worse if you take it with alcohol or certain medicines. Use phenylephrine/diphenhydramine/dextromethorphan suspension with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Do not drink alcohol or use medicines that may cause drowsiness (eg, sleep aids, muscle relaxers) while you are using phenylephrine/diphenhydramine/dextromethorphan suspension; it may add to their effects. Ask your pharmacist if you have questions about which medicines may cause drowsiness.
  • Some of these products contain phenylalanine. If you must have a diet that is low in phenylalanine, ask your pharmacist if it is in your product.
  • Phenylephrine/diphenhydramine/dextromethorphan suspension has phenylephrine, diphenhydramine, and dextromethorphan in it. Before you start any new medicine, check the label to see if it has phenylephrine, diphenhydramine, or dextromethorphan in it too. If it does or if you are not sure, check with your doctor or pharmacist.
  • Do not use phenylephrine/diphenhydramine/dextromethorphan suspension for a cough with a lot of mucus. Do not use it for a long-term cough (eg, caused by asthma, emphysema, smoking). However, you may use it for these conditions if your doctor tells you to.
  • Do NOT take more than the recommended dose or use for longer than prescribed without checking with your doctor.
  • If your symptoms do not get better within 5 to 7 days or if they get worse, check with your doctor.
  • Phenylephrine/diphenhydramine/dextromethorphan suspension may cause you to become sunburned more easily. Avoid the sun, sunlamps, or tanning booths until you know how you react to phenylephrine/diphenhydramine/dextromethorphan suspension. Use a sunscreen or wear protective clothing if you must be outside for more than a short time.
  • Phenylephrine/diphenhydramine/dextromethorphan suspension may interfere with skin allergy tests. If you are scheduled for a skin test, talk to your doctor. You may need to stop taking phenylephrine/diphenhydramine/dextromethorphan suspension for a few days before the tests.
  • Tell your doctor or dentist that you take phenylephrine/diphenhydramine/dextromethorphan suspension before you receive any medical or dental care, emergency care, or surgery.
  • Use phenylephrine/diphenhydramine/dextromethorphan suspension with caution in the ELDERLY; they may be more sensitive to its effects, especially dizziness or drowsiness.
  • Phenylephrine/diphenhydramine/dextromethorphan suspension should be used with extreme caution in CHILDREN younger than 2 years old; safety and effectiveness in these children have not been confirmed.
  • Caution is advised when using phenylephrine/diphenhydramine/dextromethorphan suspension in CHILDREN; they may be more sensitive to its effects, especially excitability.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using phenylephrine/diphenhydramine/dextromethorphan suspension while you are pregnant. It is not known if this medicine is found in breast milk. Do not breast-feed while taking phenylephrine/diphenhydramine/dextromethorphan suspension.

Possible side effects of phenylephrine/ diphenhydramine/ dextromethorphan suspension:

All medicines may cause side effects, but many people have no, or minor side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Blurred vision; constipation; diarrhea; dizziness; drowsiness; dry mouth, nose, or throat; excitability; headache; increased sweating; loss of appetite; nausea; nervousness or anxiety; trouble sleeping; upset stomach; vomiting; weakness.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); difficulty urinating or inability to urinate; fast or irregular heartbeat; fever, chills, or sore throat; flushing or redness of the face; hallucinations; mental or mood changes; numbness or tingling; seizures; severe dizziness, drowsiness, lightheadedness, or headache; severe dryness of mouth, nose, and throat; shortness of breath; tremor; trouble sleeping; unusual bruising or bleeding; vision changes; wheezing.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include blurred vision; confusion; hallucinations; muscle spasms; seizures; severe dizziness, lightheadedness, or headache; severe drowsiness; unusual eye movements; unusually fast, slow, or irregular heartbeat; vomiting.

Proper storage of phenylephrine/diphenhydramine/dextromethorphan suspension:

Store phenylephrine/diphenhydramine/dextromethorphan suspension at room temperature, between 68 and 77 degrees F (20 and 25 degrees C). Do not freeze. Store away from heat, moisture, and light. Do not store in the bathroom. Keep phenylephrine/diphenhydramine/dextromethorphan suspension out of the reach of children and away from pets.

General information:

  • If you have any questions about phenylephrine/diphenhydramine/dextromethorphan suspension, please talk with your doctor, pharmacist, or other health care provider.
  • Phenylephrine/diphenhydramine/dextromethorphan suspension is to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information is a summary only. It does not contain all information about phenylephrine/diphenhydramine/dextromethorphan suspension. If you have questions about the medicine you are taking or would like more information, check with your doctor, pharmacist, or other health care provider.

Review Date: August 8, 2016

Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.

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