Chlor-Trimeton vs. Zyrtec

Are Chlor-Trimeton and Zyrtec the Same Thing?

Chlor-Trimeton (chlorpheniramine maleate) and Zyrtec (cetirizine hydrochloride) are antihistamines used to treat sneezing, itching, watery eyes, and runny nose caused by allergies or the common cold.

Zyrtec is also used to treat other allergies, such as allergies to molds and dust mites.

Both Chlor-Trimeton and Zyrtec are available as generics and over-the-counter (OTC).

Side effects of Chlor-Trimeton and Zyrtec that are similar include drowsiness, dizziness, dry mouth, nausea, stomach pain, or constipation.

Side effects of Chlor-Trimeton that are different from Zyrtec include blurred vision, dry nose/throat, problems with memory or concentration, nervousness, or restlessness or excitability (especially in children).

Side effects of Zyrtec that are different from Chlor-Trimeton include fatigue, tired feeling, sore throat, cough, headache, or vomiting.

What Are Possible Side Effects of Chlor-Trimeton?

Common side effects of Chlor-Trimeton include:

  • drowsiness,
  • dizziness,
  • blurred vision,
  • dry mouth/nose/throat,
  • nausea,
  • stomach pain,
  • constipation,
  • problems with memory or concentration,
  • nervousness, or
  • restlessness or excitability (especially in children).

What Are Possible Side Effects of Zyrtec?

Common side effects of Zyrtec include:

  • drowsiness,
  • fatigue,
  • tired feeling,
  • dizziness,
  • dry mouth,
  • sore throat,
  • cough,
  • nausea,
  • constipation, or
  • headache.

In children, side effects of Zyrtec include:

  • stomach pain and
  • vomiting.

The side effect of sleepiness may occur when taking Zyrtec, so do not drive a car or operate potentially dangerous machinery.

What Is Chlor-Trimeton?

Chlor-Trimeton (chlorpheniramine maleate) is an antihistamine used to treat sneezing, itching, watery eyes, and runny nose caused by allergies or the common cold. Chlor-Trimeton is available in generic form and over-the-counter (OTC).

What Is Zyrtec?

Zyrtec is medication that temporarily relieves symptoms due to hay fever or other upper respiratory allergies.

What Drugs Interact With Chlor-Trimeton?

Some medications may interact with Chlor-Trimeton, including antidepressants, diuretics (water pills), glycopyrrolate, mepenzolate, aspirin or salicylates, atropine, belladonna, benztropine, dimenhydrinate, methscopolamine, scopolamine, bronchodilators, MAO inhibitors, bladder or urinary medications, or irritable bowel medications. Tell your doctor all drugs you are taking. Chlor-Trimeton is not expected to be harmful to a fetus. Tell your doctor if you are pregnant or plan to become pregnant during treatment. Chlor-Trimeton can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breastfeeding.

What Drugs Interact With Zyrtec?

Zyrtec may interact with alcohol, other medicines that make you sleepy (such as other cold or allergy medicine, narcotic pain medicine, sleeping pills, muscle relaxers, and medicine for seizures, depression, or anxiety).

How Should Chlor-Trimeton Be Taken?

Dose for Chlor-Trimeton for adults and children 12 years of age and older: One tablet every 4 to 6 hours, not to exceed 6 tablets in 24 hours or as directed by a physician. Children 6 through 11 years: Half the adult dose every 4 to 6 hours, not to exceed 3 whole tablets in 24 hours. Children under 6: Consult a doctor.

How Should Zyrtec Be Taken?

Adults and children 6 years and over should take one 10 mg capsule once daily; do not take more than one 10 mg capsule in 24 hours. A 5 mg product may be appropriate for less severe symptoms.

Adults 65 years of age or older, children under 6 years of age, and consumers with liver or kidney disease should consult a doctor before using this product.


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RxList. Chlor-Trimeton Product Information.

Johnson & Johnson Consumer Inc. Zyrtec Product Information.

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