Fexofenadine (Telfast)

Fexofenadine, also sold under the brand names Telfast and Allegra, is a fast-acting treatment for symptoms caused by hay fever (seasonal allergic rhinitis) as well as pet and dust mite allergies. It can also be used to treat the skin condition hives (chronic idiopathic urticaria).

Fexofenadine works by blocking the immune response, therefore preventing symptoms such as: sneezing; an itchy, blocked or runny nose; itchy, red or watery eyes and an itchy throat. It starts to work within 1 hour of taking it, and effects should last for up to 24 hours.

Fexofenadine hydrochloride is an antihistamine. It thereby works by blocking the action of a chemical called histamine in your body.

During an allergic reaction, the allergen (pollen, pet dander or dust mites) enters your body through your nose, eyes or mouth. Your body detects it and mistakes it as a harmful substance.

In response, your body produces the chemical histamine which then triggers an immune response to that allergen. This is what causes allergy symptoms. Fexofenadine blocks this action, preventing any symptoms from occurring.

Fexofenadine is suitable for most people to take to treat hay fever or hives.

However, some patients with certain pre-existing conditions may require additional monitoring by their doctor. You should always inform your prescriber if you:

• have or have had a kidney disease
• have liver problems
• have heart problems
• have epilepsy or another condition that causes seizures
• are elderly

You should not take Fexofenadine if you have previously had an allergic reaction or any other adverse effects whilst using the drug.

In addition, Fexofenadine is not recommended for women who are pregnant or breastfeeding unless you have been advised to do so by your doctor. If you are pregnant, breastfeeding or think you may be pregnant, please consult your doctor before using Fexofenadine.

If you have any doubts or are not sure whether you can take this medicine, consult your doctor or pharmacist.

The doses of Fexofenadine available are 120mg and 180mg. The 120mg tablets are the recommended dose used to treat hay fever whilst the 180mg dose is only used to treat long-term hives.

For hay fever, you should take one 120mg tablet once daily when you develop symptoms or anticipate symptoms (i.e when the pollen count is high). You should take tablets with water before a meal.

If you miss a dose, just take the next dose at the usual time. Do not take a double dose to make up for the missed dose. If you take too many Fexofenadine tablets, you may be at risk of side effects. Seek medical attention, even if you feel fine.

As with all prescription medicines, there is a risk of experiencing side effects. However, the most common side effects tend to be mild and should disappear on their own.

Some common side effects of Fexofenadine include:

• headache
• drowsiness or sleepiness
• feeling sick
• dizziness
• dry mouth

If you experience any facial swelling or breathing difficulties, stop taking Fexofenadine and seek immediate medical attention as these may be signs of a serious allergic reaction.

For the full list of side effects, please refer to the patient information leaflet which is available to download from the top of this page.

Fexofenadine may interact with some over-the-counter heartburn and indigestion remedies, including any that contain magnesium or aluminium. You must allow for 2 hours after taking your antacid before taking Fexofenadine and vice versa.

You should also avoid drinking particular fruit juices whilst on Fexofenadine, such as grapefruit juice, orange juice and apple juice. Taking them together may increase your risk of side effects.

Drinking alcohol whilst on Fexofenadine may also increase your risk of adverse events, so it’s recommended to not drink in excess.

It’s important you consult with a healthcare professional before taking Fexofenadine or any medicine, as it may interact with the medicines you already take including any prescription, over-the-counter medicines or supplements.

Potential drug interactions may include with:

• ketoconazole - used to treat fungal infections
• erythromycin and rifampicin - antibiotics used to treat certain bacterial infections
• filgotinib or leflunomide - used to treat arthritis
• teriflunomide - used to treat multiple sclerosis
• letermovir - prescribed after a stem cell transplant
• pibrentasvir or velpatasvir - used to treat a hepatitis C infection
• cancer medicines
• other antihistamines (e.g cetirizine, levocetirizine, loratadine, desloratadine)

If you’re not sure whether you take any of these medicines, consult your doctor or pharmacist before taking Fexofenadine.

Fexofenadine 120mg is available as both the generic and the brand Telfast at euroClinix. All you have to do is fill out a quick medical questionnaire that will be reviewed by one of our UK registered doctors. Once approved for treatment, your medicine will be dispensed and delivered to your address the following day.