Health Library

Chlorpheniramine/methscopolamine/phenylephrine (By mouth)

Chlorpheniramine Maleate (klor-fen-IR-a-meen MAL-ee-ate), Methscopolamine Nitrate (meth-skoe-POL-a-meen NYE-trate), Phenylephrine Hydrochloride (fen-il-EF-rin hye-droe-KLOR-ide)

Treats runny nose, stuffy nose, sneezing, watery eyes, or other symptoms caused by a cold or allergy.

Brand Name(s):

When This Medicine Should Not Be Used:

How to Use This Medicine:

Liquid, Long Acting Tablet

• Your doctor will tell you how much medicine to use. Do not use more than directed.
• Swallow the extended-release tablet whole. If you have trouble swallowing it, you may break the tablet in half before taking it. Do not crush or chew the extended-release tablet.
• This medicine should be taken 30 minutes to one hour before meals. You may also take this medicine with food, water, or milk to decrease stomach irritation.

If a dose is missed:

• Take a dose as soon as you remember. If it is almost time for your next dose, wait until then and take a regular dose. Do not take extra medicine to make up for a missed dose.

How to Store and Dispose of This Medicine:

• Store the medicine in a closed container at room temperature, away from heat, moisture, and direct light.
• Ask your pharmacist, doctor, or health caregiver about the best way to dispose of any outdated medicine or medicine no longer needed.
• Keep all medicine out of the reach of children. Never share your medicine with anyone.

Drugs and Foods to Avoid:

Ask your doctor or pharmacist before using any other medicine, including over-the-counter medicines, vitamins, and herbal products.

• Make sure your doctor knows if you are using an alpha-blocker medicine (such as doxazosin, terazosin, Cardura®, or Hytrin®), antacids (Maalox®, Mylanta®), medicines to treat diarrhea (such as diphenoxylate/atropine, loperamide, Imodium®, Lomocot®, or Lomotil®), or medicines used for numbing in surgery (such as chloroform, cyclopropane, enflurane, halothane, isoflurane, methoxyflurane, or trichloroethylene). Tell your doctor if you are using medicines to treat depression (such as amitriptyline, doxepin, nortriptyline, Elavil®, Pamelor®, or Sinequan®), anticholinergic medicines (such as biperidon, oxybutynin, propantheline, Akineton®, or Ditropan®), acetazolamide (Diamox®), or medicines that contain citrates, sodium bicarbonate, or potassium chloride.
• Make sure your doctor knows if you are using an MAO inhibitor (such as Eldepryl®, Marplan®, Nardil®, or Parnate®) or have used one within the past 14 days.
• Tell your doctor if you are also using beta-blocker medicines to lower blood pressure (such as atenolol, labetalol, metoprolol, Inderal®, Toprol®, or Tenormin®), diuretics or "water pills" (such as furosemide, HCTZ, hydrochlorothiazide, or Lasix®), cocaine, digoxin (Digitek®), ergot medicines (such as Cafergot® or Ergomar®), reserpine, ketoconazole (Nizoral®), or methyldopa (Aldomet®).
• Tell your doctor if you use anything else that makes you sleepy. Some examples are allergy medicine, narcotic pain medicine, and alcohol.
• Do not drink alcohol while you are using this medicine.

Warnings While Using This Medicine:

• Make sure your doctor knows if you are pregnant or breastfeeding, or if you have asthma, bladder problems, or a problem with passing urine including an enlarged prostate. Tell your doctor if you have heart or blood vessel disease, a history of blood clots, heart rhythm problems, high blood pressure, diabetes, or Down's syndrome.
• Make sure your doctor knows if you have reflux esophagitis, problems with your esophagus or stomach, blocked bowels, or problems with bowel movements. Tell your doctor if you have glaucoma, any active bleeding problems, liver disease, a hernia, an overactive thyroid, lung disease, a metabolic disease, mental illness, kidney disease, or any condition that may cause dry mouth.
• This medicine may cause blurred vision or make your eyes more sensitive to light. This medicine may also make you dizzy or drowsy. Avoid driving, using machines, or doing anything else that could be dangerous if you cannot see clearly or if you are not alert.
• This medicine may make you more sensitive to heat and cause you to sweat less than normal. Be careful when exercising or doing things in places that are very hot such as outdoors.
• This medicine can be habit-forming. Do not use more than your prescribed dose. Call your doctor if you think your medicine is not working.
• Tell any doctor or dentist who treats you that you are using this medicine. This medicine may affect certain medical test results.
• Call your doctor if your symptoms do not improve or if they get worse.

Possible Side Effects While Using This Medicine:

Call your doctor right away if you notice any of these side effects:

• Allergic reaction: Itching or hives, swelling in your face or hands, swelling or tingling in your mouth or throat, chest tightness, trouble breathing
• Fast or irregular heartbeat.
• Lightheadedness or fainting.
• Seeing, hearing, or feeling things that are not really there.
• Severe drowsiness or dizziness.
• Tremors.
• Trouble breathing.
• Trouble urinating or pain on urination.
• Unusual bleeding or bruising.
• Unusual tiredness or weakness.

If you notice these less serious side effects, talk with your doctor:

• Blurred vision.
• Dry mouth, nose, or throat.
• Headache.
• Increased or decreased sweating.
• Loss of appetite.
• Nervousness, restlessness, irritability, agitation, nightmares, unusual excitement, confusion, or other mood or mental changes.
• Skin rash.
• Stomach upset or pain.
• Tingling in hands or feet.
• Vomiting.
• Warmth or redness in your face, neck, arms, or upper chest.

If you notice other side effects that you think are caused by this medicine, tell your doctor

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088

Last Updated: 9/6/2024