Clemastine (clemastine fumigate)

What is clemastine?

Clemastine is an antihistamine available in over-the-counter (OTC) medicines that temporarily reduce symptoms due to the common cold, hay fever, or other respiratory allergies and can be found in allergy medicines.

What is clemastine used to treat?

  • Common colds
  • Hay fever
  • Respiratory allergies
Common brands containing clemastine:
  • GoodSense® Dayhist®
  • Tavist®
  • Store Brands (ex. Walmart’s “Equate” store brand or CVS Health store brand)

How much clemastine can you take?

Different types of products containing this active ingredient have different strengths. That’s why it is always important to read and follow the Drug Facts label. Most medicines warn against use of an active ingredient for longer than 7-10 days. Stop use and ask a doctor if symptoms persist.

Safety guide for clemastine

Clemastine is approved by the U.S. Food and Drug Administration (FDA) and is safe and effective when used according to the Drug Facts label directions.

Ask a healthcare provider before use if:

  • You have a breathing problem such as emphysema or chronic bronchitis.
  • You have glaucoma.
  • You have trouble urinating due to an enlarged prostate gland.
  • You are taking sedatives or tranquilizers.
  • You are pregnant or breastfeeding.
  • Before giving to a child under 12 years old.

Do not use if:

  • Do not use this product to treat cold symptoms in children younger than 6 years unless specifically directed by your doctor.

Stop use and ask a doctor if:

  • You take too much. Immediately contact a healthcare provider or the poison control national helpline at 800.222.1222.

What are the side effects of clemastine?

  • Drowsiness may occur. You should avoid alcoholic drinks and use care when driving a motor vehicle or operating machinery.
  • Using alcohol, sedatives, and tranquilizers while taking these medicines may increase drowsiness.
  • Excitability may occur, especially in children.