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. It may be written as clemastine or clemastine fumigate, but it is the same active ingredient. Clemastine can be found in allergy medicines.

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. Clemastine-containing medicines may cause drowsiness. Speak to a healthcare provider before using an allergy medicine containing clemastine if you are currently taking sedatives or tranquilizers.

  • 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.
  • You take too much. Immediately contact a healthcare provider or the poison control national helpline at 800.222.1222.
  • Talk to a healthcare provider before giving an OTC allergy medicine containing clemastine to a child under the age of 12.
  • OTC allergy medicines containing clemastine may cause excitability in children.
  • Click here for more information on giving OTCs to children.