Skip to Content
UW Health SMPH
American Family Children's Hospital
SHARE TEXT

chlorpheniramine, phenyltoloxamine, and phenylephrine

Pronunciation: klor fen IR a meen/fen ill toe LOX a meen/fen ill EFF rin

Brand: C-Hist-SR, Chlortox, Comhist, Linhist-L.A., Nalex-A

What is the most important information I should know about chlorpheniramine, phenyltoloxamine, and phenylephrine?

Multum dizzy

Use caution when driving, operating machinery, or performing other hazardous activities. Chlorpheniramine, phenyltoloxamine, and phenylephrine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Multum noalcohol

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while taking chlorpheniramine, phenyltoloxamine, and phenylephrine.

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

What is chlorpheniramine, phenyltoloxamine, and phenylephrine?

Chlorpheniramine and phenyltoloxamine are antihistamines. They block the effects of the naturally occurring chemical histamine in the body. Chlorpheniramine and phenyltoloxamine prevent sneezing; itchy, watery eyes and nose; and other symptoms of allergies and hay fever.

Phenylephrine is a decongestant. It constricts (shrinks) blood vessels (veins and arteries). This reduces the blood flow to certain areas and allows nasal passages to open up.

Chlorpheniramine, phenyltoloxamine, and phenylephrine is used to treat nasal congestion and sinusitis (inflammation of the sinuses) associated with allergies, hay fever, and the common cold.

Chlorpheniramine, phenyltoloxamine, and phenylephrine may also be used for purposes other than those listed in this medication guide.

Who should not take chlorpheniramine, phenyltoloxamine, and phenylephrine?

Multum donot

Do not take chlorpheniramine, phenyltoloxamine, and phenylephrine 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,
  • heart disease or high blood pressure,
  • thyroid disease,
  • emphysema or chronic bronchitis, or
  • difficulty urinating or an enlarged prostate.

You may not be able to take chlorpheniramine, phenyltoloxamine, and phenylephrine, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above.

Chlorpheniramine, phenyltoloxamine, and phenylephrine is in the FDA pregnancy category B. This means that it is unlikely to harm an unborn baby. Do not take this medication without first talking to your doctor if you are pregnant.

Multum nobrfeed

This medication passes into breast milk and may harm a nursing baby. Do not take this medication without first talking to your doctor if you are breast-feeding a baby.

If you are over 60 years of age, you may be more likely to experience side effects from chlorpheniramine, phenyltoloxamine, and phenylephrine. 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 chlorpheniramine, phenyltoloxamine, and phenylephrine?

Take chlorpheniramine, phenyltoloxamine, and phenylephrine exactly as directed. If you do not understand these directions, ask your pharmacist, nurse, or doctor to explain them to you.

Multum water

Take each dose with a full glass of water.

Multum nocrush

Do not crush, chew, or break the long-acting or sustained-release forms of this medication. Swallow it whole. If you are unsure of the formulation of the medicine, ask your pharmacist for help.

If you cannot swallow the tablets or capsules, look for a liquid form of the medication.

Multum donot

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

Do not take chlorpheniramine, phenyltoloxamine, and phenylephrine 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.

Multum rt

Store chlorpheniramine, phenyltoloxamine, and phenylephrine 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?

Multum emt

Seek emergency medical attention.

Symptoms of a chlorpheniramine, phenyltoloxamine, and phenylephrine overdose include a dry mouth, large pupils, flushing, nausea, and vomiting.

What should I avoid while taking chlorpheniramine, phenyltoloxamine, and phenylephrine?

Multum dizzy

Use caution when driving, operating machinery, or performing other hazardous activities. Chlorpheniramine, phenyltoloxamine, and phenylephrine may cause dizziness or drowsiness. If you experience dizziness or drowsiness, avoid these activities.

Multum noalcohol

Use alcohol cautiously. Alcohol may increase drowsiness and dizziness while taking chlorpheniramine, phenyltoloxamine, and phenylephrine.

Chlorpheniramine, phenyltoloxamine, and phenylephrine 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 chlorpheniramine, phenyltoloxamine, and phenylephrine is taken with any of these medications.

What are the possible side effects of chlorpheniramine, phenyltoloxamine, and phenylephrine?

Multum emt

Serious side effects are unlikely to occur. Stop taking chlorpheniramine, phenyltoloxamine, and phenylephrine 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 chlorpheniramine, phenyltoloxamine, and phenylephrine 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. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect chlorpheniramine, phenyltoloxamine, and phenylephrine?

Multum donot

Do not take chlorpheniramine, phenyltoloxamine, and phenylephrine 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, pain, or sleep medications while taking chlorpheniramine, phenyltoloxamine, and phenylephrine without first talking to your pharmacist or doctor. Other medications may also contain chlorpheniramine, phenyltoloxamine, phenylephrine, or other similar drugs, and you may accidentally take too much of these medicines.

Chlorpheniramine, phenyltoloxamine, and phenylephrine 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 chlorpheniramine, phenyltoloxamine, and phenylephrine is taken with any of these medications.

Drugs other than those listed here may also interact with chlorpheniramine, phenyltoloxamine, and phenylephrine. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including herbal products.

Where can I get more information?

Your pharmacist has additional information about chlorpheniramine, phenyltoloxamine, and phenylephrine written for health professionals that you may read.


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.

Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2013 Cerner Multum, Inc. Version: 5.05. Revision date: 12/15/2010.

Your use of the content provided in this service indicates that you have read, understood and agree to the End-User License Agreement, which can be accessed by clicking on this link.

This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use. How this information was developed to help you make better health decisions.

Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.