Generic Name: dexchlorpheniramine/phenylephrine (DEX-klor-fen-IR-a-meen/FEN-il-EF-rin)
Brand Name: Examples include NalDex and RhinaHist
NalDex is used for:
Relieving symptoms of sinus congestion, sinus pressure, watery eyes, runny nose, and sneezing caused by colds, upper respiratory infections, and allergies. It may also be used for other conditions as determined by your doctor.
NalDex is an antihistamine and decongestant combination. The antihistamine works by blocking the action of histamine, which helps reduce symptoms such as watery eyes and sneezing. The decongestant works by promoting sinus and nasal drainage, which relieves congestion and pressure.
Do NOT use NalDex if:
- you are allergic to any ingredient in NalDex
- you have severe high blood pressure, severe heart blood vessel disease, rapid heartbeat, or severe heart problems
- you are unable to urinate or are having an asthma attack
- you are taking droxidopa or 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 NalDex:
Some medical conditions may interact with NalDex. 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 history of adrenal gland problems (eg, an adrenal gland tumor); heart problems (eg, cor pulmonale; fast, slow, or irregular heartbeat); high blood pressure; diabetes; liver or kidney problems; myasthenia gravis; nervous system problems; mental or mood problems; dry mouth; blood vessel problems; a stroke; glaucoma or increased pressure in the eye; seizures; or thyroid problems
- if you have a history of asthma or other breathing problems, chronic cough, lung problems (eg, chronic bronchitis, emphysema), chronic obstructive pulmonary disease (COPD), or sleep apnea
- if you have a blockage of your bladder, stomach, or bowels; stomach or bowel problems (eg, ulcers, reflux); trouble sleeping; trouble urinating; an enlarged prostate or other prostate problems; or Down syndrome
Some MEDICINES MAY INTERACT with NalDex. 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 a heart attack may be increased
- Barbiturates (eg, phenobarbital), beta-blockers (eg, propranolol), catechol-O-methyltransferase (COMT) inhibitors (eg, tolcapone), furazolidone, indomethacin, linezolid, MAOIs (eg, phenelzine), sodium oxybate (GHB), or tricyclic antidepressants (eg, amitriptyline) because they may increase the risk of NalDex's side effects
- Bromocriptine or hydantoins (eg, phenytoin) because the risk of their side effects may be increased by NalDex
- Guanadrel, guanethidine, mecamylamine, methyldopa, or reserpine because their effectiveness may be decreased by NalDex
This may not be a complete list of all interactions that may occur. Ask your health care provider if NalDex 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 NalDex:
Use NalDex as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Take NalDex by mouth with or without food. If stomach upset occurs, take with food to reduce stomach irritation.
- If you miss a dose of NalDex and you are taking it regularly, 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 NalDex.
Important safety information:
- NalDex may cause drowsiness, dizziness, or blurred vision. These effects may be worse if you take it with alcohol or certain medicines. Use NalDex 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 NalDex; it may add to their effects. Ask your pharmacist if you have questions about which medicines may cause drowsiness.
- Do not take diet or appetite control medicines while you are taking NalDex without checking with your doctor.
- NalDex has an antihistamine and a decongestant in it. Before you start any new medicine, check the label to see if it has a decongestant or antihistamine in it too. If it does or if you are not sure, check with your doctor or pharmacist.
- 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.
- NalDex may cause you to become sunburned more easily. Avoid the sun, sunlamps, or tanning booths until you know how you react to NalDex. Use a sunscreen or wear protective clothing if you must be outside for more than a short time.
- NalDex may interfere with skin allergy tests. If you are scheduled for a skin test, talk to your doctor. You may need to stop taking NalDex for a few days before the tests.
- Tell your doctor or dentist that you take NalDex before you receive any medical or dental care, emergency care, or surgery.
- Use NalDex with caution in the ELDERLY; they may be more sensitive to its effects, especially confusion, dizziness, drowsiness, dry mouth, excitability, low blood pressure, and trouble urinating.
- Caution is advised when using NalDex in CHILDREN; they may be more sensitive to its effects, especially excitability.
- Different brands of NalDex may have different dosing instructions for CHILDREN. Follow the dosing instructions that your doctor has given you. Talk to your doctor if you have any questions or concerns about giving NalDex to your child.
- PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of taking NalDex while you are pregnant. It is not known if NalDex is found in breast milk. Do not breast-feed while taking NalDex.
Possible side effects of NalDex:
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:
Seek medical attention right away if any of these SEVERE side effects occur:
Constipation; diarrhea; dizziness; drowsiness; dry mouth; excitability; headache; loss of appetite; nausea; nervousness or anxiety; trouble sleeping; upset stomach; vomiting; weakness.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); blurred vision or other vision changes; difficulty urinating or inability to urinate; fast or irregular heartbeat; fever, chills, or persistent sore throat; hallucinations; mood or mental changes; persistent trouble sleeping; restlessness; seizures; severe dizziness, light-headedness, or headache; severe drowsiness; tremor.
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; ringing in the ears; seizures; severe dizziness, light-headedness, or headache; severe drowsiness; unusually fast, slow, or irregular breathing; unusually fast, slow, or irregular heartbeat.Proper storage of NalDex:
Store NalDex at room temperature, between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep NalDex out of the reach of children and away from pets.
- If you have any questions about NalDex, please talk with your doctor, pharmacist, or other health care provider.
- NalDex 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 should not be used to decide whether or not to take NalDex 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 NalDex. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to NalDex. 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 NalDex.
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.