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Telfast is a antihistamine for sneezing, itchy eyes, and congestion.

Last Modified: 09 May 2024

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What is Telfast?

Telfast is an antihistamine brand, known for its relief of symptoms of allergy. The active ingredient in Telfast is fexofenadine hydrochloride, a second-generation antihistamine less likely to cause drowsiness.

Fexofenadine hydrochloride is created through a synthetic process involving multiple chemical reactions. It's designed to selectively target peripheral histamine H1-receptors, reducing the likelihood of crossing the blood-brain barrier and causing sedation.

Global Name

The generic name for Telfast is "fexofenadine." It is known by various brand names worldwide, with "Allegra" being another common name, especially in the United States. The formulation, whether it includes a decongestant like pseudoephedrine as in Telfast D, may also have different names based on the region and manufacturer.


What is Telfast used for?

Telfast is primarily used to alleviate symptoms of allergy/hypersensitivity such as:

  • Seasonal allergic rhinitis (hay fever)
  • Chronic urticaria (hives)
  • Itching and runny nose
  • Sneezing
  • Itchy, watery eyes
  • Acute food and drug allergy

How do you use Telfast?


Telfast is available in several forms, including:

  • Tablets
  • Oral suspension
  • Quick-dissolving tablets

Dosage Information:

  • Adults and Children over 12 years: 60 mg twice daily or 180 mg once daily.
  • Children 6-11 years: 30 mg twice daily.

Suitable for:

  • Children (specific dosages)
  • Adults
  • Elderlies (no dosage adjustment typically necessary)
  • While Telfast (fexofenadine) is generally considered to be low-risk for use during pregnancy and breastfeeding, it is always important for expectant or nursing mothers to consult with their healthcare provider before using any medication.

Not Suitable for:

  • Children under 6 years for certain forms
  • People with hypersensitivity to fexofenadine

Allergies and Warnings:

  • Known allergy to fexofenadine hydrochloride or any other ingredients in Telfast

Precautions and Interactions:

  • Caution when used with antacids containing aluminum and magnesium
  • Consume with water, not fruit juice, for optimal absorption


  • Severe kidney disease without medical advice

Side Effects

Common side effects may include:

  • Headache
  • Drowsiness (rare)
  • Nausea

Pharmacist Tips

  • Store Telfast in a cool, dry place, away from direct sunlight.
  • Keep the medication in its original packaging.


Where is Telfast available in Hong Kong?

Telfast is available in pharmacies throughout Hong Kong, with a prescription for higher doses and over-the-counter for lower doses.


What is the difference between Telfast and Telfast D?

Telfast contains fexofenadine as the active ingredient, an antihistamine for allergy symptoms. Telfast D adds pseudoephedrine as an active component, targeting nasal congestion. Telfast suffices for most allergies however, if a blocked nasal passage is a concern, then Telfast D offers the advantage of decongestion. Please consult a healthcare provider for personalised advice.

Can Telfast be taken with food?

Yes, Telfast can be taken with or without food, but avoid taking it with fruit juices as they can affect absorption.

Can Telfast cause drowsiness?

Telfast is less likely to cause drowsiness than first-generation antihistamines, but many people may still experience this side effect.

How quickly does Telfast work?

Telfast typically begins to work within an hour of ingestion, relieving allergy symptoms.

This website provides content related to drug use and medicine for informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Do not use the information on this website to diagnose or treat a health problem or disease without consulting a qualified healthcare provider. The website's owners and contributors are not liable for any repercussions, adverse effects, or consequences resulting from the use of any medication or information provided herein.

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