Durahist D contains a combination of dexchlorpheniramine, methscopolamine, and pseudoephedrine.

Dexchlorpheniramine is an antihistamine that reduces the natural chemical histamine in the body. Histamine can produce symptoms of sneezing, itching, watery eyes, and runny nose. Methscopolamine reduces secretion of fluids in the body that cause sneezing, runny nose, and postnasal drip. Pseudoephedrine is a decongestant that shrinks blood vessels in the nasal passages. Dilated blood vessels can cause nasal congestion (stuffy nose).

Durahist D is used to treat runny or stuffy nose, sneezing, watery eyes, and sinus congestion caused by allergies, the common cold, or the flu.

Durahist D may also be used for purposes not listed here.

Do not take Durahist D if you have used a monoamine oxidase inhibitor (MAOI) such as furazolidone (Furoxone), isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects.

Drinking alcohol can increase certain side effects of Durahist D. Before using this medication, tell your doctor if you regularly use other medicines that make you sleepy (such as cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by methscopolamine.

Ask a doctor or pharmacist before using any other cold or allergy medicine when you also taking Durahist D. Antihistamines and decongestants are contained in many combination medicines. Taking certain products together can cause you to get too much of a certain drug. Check the label to see if a medicine contains an antihistamine or decongestant.

Avoid taking diet pills, caffeine pills, or other stimulants (such as ADHD medications) without your doctor's advice. Taking a stimulant together with the decongestant found in Durahist D can increase your risk of unpleasant side effects.

Do not take Durahist D for longer than 7 days in a row. If your symptoms do not improve, or if they get worse and you also have a fever, talk to your doctor.

Take Durahist D exactly as prescribed by your doctor. Do not take in larger or smaller amounts or for longer than recommended. Follow the directions on your prescription label.

You may take Durahist D with or without food.

Swallow the tablet with a full glass of water. Do not crush or chew the tablet. Swallow the pill whole. To make the tablet easier to swallow, you may break it in half where the tablet is scored.

Do not take Durahist D for longer than 7 days in a row. If your symptoms do not improve, or if they get worse and you also have a fever, talk to your doctor.

Store Durahist D at room temperature away from moisture and heat.

You should not use Durahist D if you are allergic to dexchlorpheniramine, methscopolamine, or pseudoephedrine. Do not take Durahist D if you have used a monoamine oxidase inhibitor (MAOI) such as furazolidone (Furoxone), isocarboxazid (Marplan), phenelzine (Nardil), rasagiline (Azilect), selegiline (Eldepryl, Emsam, Zelapar), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects.

If you have any of these other conditions, you may need to adjust the dose of Durahist D or have special tests:

• epilepsy or another seizure disorder;

• peripheral vascular disease such as Raynaud's syndrome;

• thyroid problems;

• asthma, emphysema, or chronic obstructive pulmonary disease (COPD);

• diabetes;

• glaucoma;

• an ulcer or an obstruction in the stomach;

• hiatal hernia or reflux disease;

• bladder problems or difficulty urinating;

• an enlarged prostate;

• high blood pressure, irregular heartbeats, or any type of heart disease; or

• myasthenia gravis.

FDA pregnancy category C. It is not known whether Durahist D will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant while using Durahist D. This medication can pass into breast milk and may harm a nursing baby. Do not use Durahist D without telling your doctor if you are breast-feeding a baby.

Older adults may be more likely to have side effects from Durahist D.

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Overdose symptoms may include a dry mouth, large pupils, flushing, nausea, vomiting, and seizures.

Durahist D may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be alert. Drinking alcohol can increase certain side effects of this medication.

Ask a doctor or pharmacist before using any other cold or allergy medicine. Antihistamines and decongestants are contained in many combination medicines. Taking certain products together can cause you to get too much of a certain drug. Check the label to see if a medicine contains an antihistamine or decongestant.

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

Get emergency medical help if you have any of these signs of an allergic reaction to Durahist D: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have any of these serious side effects:

• fast or irregular heart rate;

• feeling like you might pass out;

• rash or flushing; or

• eye pain.

Less serious Durahist D side effects may include:

• dryness of your eyes, nose, and mouth;

• blurred vision;

• headache, dizziness;

• weakness or nervousness;

• nausea, bloating, heartburn, or constipation;

• changes in taste;

• difficulty urinating;

• decreased sweating; or

• feeling restless or excited (especially in children).

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.

Before using Durahist D, tell your doctor if you regularly use other medicines that make you sleepy (such as cold or allergy medicine, sedatives, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety). They can add to sleepiness caused by methscopolamine. Many drugs can interact with Durahist D. Below is just a partial list. Tell your doctor if you are using any of these:

• pramlintide (Symlin);

• blood pressure medications;

• potassium supplements;

• antidepressants such as amitriptyline (Elavil, Etrafon), doxepin (Sinequan), imipramine (Janimine, Tofranil), nortriptyline (Pamelor), and others;

• migraine headache medications such as sumatriptan (Imitrex) and others; or

• medicine to treat mental illness, such as chlorpromazine (Thorazine), risperidone (Risperdal), or trazodone (Desyrel).

This list is not complete and other drugs may interact with Durahist D. Tell your doctor about all medications you use. This includes prescription, over-the-counter, vitamin, and herbal products. Do not start a new medication without telling your doctor.