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Trihist DM

Generic Name: brompheniramine/dextromethorphan/phenylpropanolamine (brome fen IR a meen/dex troe meth OR fan/fen ill proe pa NOLE a meen)
Brand Name: Delhistine DM, Dimetapp Cold and Cough Liquigel, Dimetapp DM, DM Cold and Cough, Histinex DM, Iohist DM, Liquihistine DM, Poly DM, Poly Histine DM, Prohistine DM, Trihist DM

What is Trihist DM (brompheniramine/dextromethorphan/phenylpropanolamine)?

Brompheniramine is an antihistamine. It blocks the effects of the naturally occurring chemical histamine in your body. Brompheniramine prevents sneezing; itchy, watery eyes and nose; and other symptoms of allergies and hay fever.

Dextromethorphan is a cough suppressant. It suppresses an area in the brain that causes coughing

Phenylpropanolamine is a decongestant. It constricts (shrinks) blood vessels (veins and arteries). This reduces the blood flow, allowing nasal passages to open up.

Brompheniramine/dextromethorphan/phenylpropanolamine is used to treat nasal congestion, sinusitis (inflammation of the sinuses), and coughs associated with allergies, hay fever, and the common cold.

Phenylpropanolamine, an ingredient in this product, has been associated with an increased risk of hemorrhagic stroke (bleeding into the brain or into tissue surrounding the brain) in women. Men may also be at risk. Although the risk of hemorrhagic stroke is low, the U.S. Food and Drug Administration (FDA) recommends that consumers not use any products that contain phenylpropanolamine.

Brompheniramine/dextromethorphan/phenylpropanolamine may also be used for purposes other than those listed in this medication guide.

What is the most important information I should know about Trihist DM (brompheniramine/dextromethorphan/phenylpropanolamine)?

Phenylpropanolamine, an ingredient in this product, has been associated with an increased risk of hemorrhagic stroke (bleeding into the brain or into tissue surrounding the brain) in women. Men may also be at risk. Although the risk of hemorrhagic stroke is low, the U.S. Food and Drug Administration (FDA) recommends that consumers not use any products that contain phenylpropanolamine.

Use caution when driving, operating machinery, or performing other hazardous activities. Brompheniramine/dextromethorphan/phenylpropanolamine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while taking brompheniramine/dextromethorphan/phenylpropanolamine.

Do not take more of this medication than is recommended. If your symptoms do not improve, or if they worsen, talk to your doctor.

Who should not take Trihist DM (brompheniramine/dextromethorphan/phenylpropanolamine)?

Do not take brompheniramine/dextromethorphan/phenylpropanolamine if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects.

Before taking this medication, tell your doctor if you have

  • kidney disease,

  • liver disease,

  • diabetes,

  • glaucoma,

  • any type of heart disease or high blood pressure,

  • thyroid disease,

  • emphysema or chronic bronchitis, or

  • difficulty urinating or have an enlarged prostate.

You may not be able to take brompheniramine/dextromethorphan/phenylpropanolamine, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.

It is not known whether brompheniramine/dextromethorphan/phenylpropanolamine will harm an unborn baby. Do not take this medication without first talking to your doctor if you are pregnant.

Brompheniramine/dextromethorphan/phenylpropanolamine passes into breast milk. Do not take this medication without first talking to your doctor if you are breast-feeding a baby.

If you are over 65 years of age, you may be more likely to experience side effects from brompheniramine/dextromethorphan/phenylpropanolamine. You may require a lower dose of this medication.

Read the package label for directions or consult your doctor or pharmacist before treating a child with this medication. Children are more susceptible than adults to the effects of medicines and may have unusual reactions.

How should I take Trihist DM (brompheniramine/dextromethorphan/phenylpropanolamine)?

Take brompheniramine/dextromethorphan/phenylpropanolamine exactly as directed. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

Take each dose with a full glass of water.

To ensure that you get a correct dose, measure the liquid forms of brompheniramine/dextromethorphan/phenylpropanolamine with a special dose-measuring spoon or cup, not with a regular table spoon. If you do not have a dose-measuring device, ask your pharmacist where you can get one.

Do not take more of this medication than is recommended. An overdose of this medication can cause serious harm.

Do not take brompheniramine/dextromethorphan/phenylpropanolamine for longer than 7 days in a row. If your symptoms do not improve, if they get worse, or if you have a fever, talk to your doctor.

Store brompheniramine/dextromethorphan/phenylpropanolamine at room temperature away from moisture and heat.

What happens if I miss a dose?

Take the missed dose as soon as you remember. However, if it is almost time for the next dose, skip the missed dose and take only the next regularly scheduled dose. Do not take a double dose of this medication.

What happens if I overdose?

Seek emergency medical attention.

Symptoms of a brompheniramine/dextromethorphan/phenylpropanolamine overdose include dry mouth, large pupils, flushing, nausea, vomiting, hyperactivity, or hallucinations.

What should I avoid while taking Trihist DM (brompheniramine/dextromethorphan/phenylpropanolamine)?

Use caution when driving, operating machinery, or performing other hazardous activities. Brompheniramine/dextromethorphan/phenylpropanolamine may cause dizziness. If you experience dizziness, avoid these activities.

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while taking brompheniramine/dextromethorphan/phenylpropanolamine.

Brompheniramine/dextromethorphan/phenylpropanolamine may increase the effects of other drugs that cause drowsiness, including antidepressants, alcohol, other antihistamines, pain relievers, anxiety medicines, seizure medicines, and muscle relaxants. Dangerous sedation, dizziness, or drowsiness may occur if brompheniramine/dextromethorphan/phenylpropanolamine is taken with any of these medications.

Trihist DM (brompheniramine/dextromethorphan/phenylpropanolamine) side effects

Serious side effects are unlikely to occur. Stop taking brompheniramine/dextromethorphan/phenylpropanolamine and seek emergency medical attention if you experience an allergic reaction (difficulty breathing; closing of your throat; swelling of your lips, tongue, or face; or hives).

Other, less serious side effects may be more likely to occur. Continue to take brompheniramine/dextromethorphan/phenylpropanolamine and talk to your doctor or try another similar medication if you experience

  • dryness of the eyes, nose, and mouth;

  • drowsiness or dizziness;

  • blurred vision;

  • difficulty urinating; or

  • excitation in children.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

What other drugs will affect Trihist DM (brompheniramine/dextromethorphan/phenylpropanolamine)?

Do not take brompheniramine/dextromethorphan/phenylpropanolamine if you have taken a monoamine oxidase inhibitor (MAOI) such as isocarboxazid (Marplan), phenelzine (Nardil), or tranylcypromine (Parnate) in the last 14 days. A dangerous drug interaction could occur, leading to serious side effects.

Do not take other over-the-counter cough, cold, allergy, diet, or sleep aids while taking brompheniramine/dextromethorphan/phenylpropanolamine without first talking to your doctor or pharmacist. Other medications may also contain brompheniramine, dextromethorphan, phenylpropanolamine, or other similar drugs. You may accidentally take too much of these medicines.

Brompheniramine/dextromethorphan/phenylpropanolamine may increase the effects of other drugs that cause drowsiness, including antidepressants, alcohol, other antihistamines, pain relievers, anxiety medicines, seizure medicines, and muscle relaxants. Dangerous sedation, dizziness, or drowsiness may occur if brompheniramine/dextromethorphan/phenylpropanolamine is taken with any of these medications.

Drugs other than those listed here may also interact with brompheniramine/dextromethorphan/phenylpropanolamine. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines.

Further information

  • Your pharmacist has additional information about brompheniramine/ dextromethorphan/phenylpropanolamine written for health professionals that you may read.

What does my medication look like?

Brompheniramine/dextromethorphan/phenylpropanolamine is available over the counter and with a prescription in many different formulations. Ask your pharmacist any questions you have about this medication, especially if it is new to you.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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