Generic name: Clemastine fumarate.

Other brand names: Tavist-1, Tavist-D.

Tavist is an antihistamine. Antihistamines block the effects of histamine, a body chemical that causes swelling and itchfng.

Quick Facts About Tavist


Used to treat hay fever symptoms including sneezing, runny nose, itching, and watery eyes. Also used to treat mild allergic skin reactions such as hives and swelling; to reduce itching and swelling; and to dry up eye, nose, and throat secretions.

Tavist Dosage

Take exactly as prescribed.

  • Usual adult dose: Tavist tablets — l tablet taken 3 times per day, not to exceed 3 tablets per day. Tavist-1 tablets — 1 tablet taken 2 times per day, not to exceed 6 tablets per day. Tavist syrup — For hay fever — 2 teaspoonfuls taken 2 times per day, not to exceed 12 teaspoonfuls per day. For hives and swelling — 4 teaspoonfuls taken 2 times per day, not to exceed 12 teaspoonfuls per day.
  • Usual child dose: for hay fever — 1 teaspoon taken 2 times per day, not to exceed 6 teaspoonfuls per day. For hives and swelling — 2 teaspoonfuls taken 2 times per day, not to exceed 6 teaspoonfuls per day. Not prescribed for children under 12 years.
  • Missed dose: if taking on a regular schedule — take as soon as possible, unless almost time for next dose. In that case, do not take missed dose; go back to regular schedule. Do not double doses.

Tavist Side Effects

Overdose symptoms:

coma, convulsions, drowsiness, dry mouth, fever, fixed or dilated pupils, flushing, stimulation (especially in children), stomach and intestinal problems. Overdose symptoms in children: bluish color to the skin; convulsions; excitement; hallucinations; high body temperature; slow, twisting movements of hand and arms; tremors; twitching; uncoordinated movements. If you suspect an overdose, immediately seek medical attention.

More common side effects: disturbed coordination, dizziness, drowsiness, extreme calm, sleepiness, upset stomach.

Less common or rare Tavist side effects: acute inflammation of the inner ear; anemia; blurred vision; chills; confusion; constipation; convulsions; diarrhea; difficulty sleeping; difficulty urinating; double vision; dry mouth, nose, and throat; early menstruation; exaggerated sense of well-being; excessive perspiration; excitement; fatigue; frequent urination; headache; hives; hysteria; inability to urinate; increased chest congestion; irregular heartbeat; irritability; loss of appetite; low blood pressure; nausea; nerve inflammation; nervousness; palpitations; rapid heartbeat; rash; restlessness; ringing in the ears; sensitivity to light; severe allergic reaction (anaphylactic shock); stuffy nose; tightness of chest; tingling or pins and needles; tremor; vertigo; vomiting; wheezing.


Avoid Tavist if you are taking a MAO inhibitor such as Nardil or Parnate.

Inform your doctor before combining Tavist with:

sedatives such as Nembutal and Seconal, tranquilizers such as Xanax and Valium.

Do not drink alcohol while taking Tavist, it increases the effects of alcohol. 

Special Cautions

If pregnant or planning to become pregnant, inform your doctor immediately. Avoid Tavist if breastfeeding.

Seniors at higher risk for experiencing dizziness, sedation, or low blood pressure.

Not generally prescribed for children under 12.

  • Do not take if sensitive to or allergic to this or antihistamines with similar compounds.
  • May cause drowsiness and impair your ability to drive a car or operate machinery. Do not take part in any activity that requires alertness.
  • Use with extreme caution if you have narrow-angle glaucoma, peptic ulcer, intestinal blockage, bladder obstruction, or enlarged prostate.
  • Use with caution if you have history of bronchial asthma, heart disease, circulatory problems, overactive thyroid, or high blood pressure.


HealthSurvey.org provides accurate and independent information prescription pills, over-the-counter medicines and natural products. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment. If you have questions about  dosage, or Tavist side effects, please contact your healthcare provider