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Generic Name: Fexofenadine HCl
Therapeutic Category:      Respiratory Agent
Pharmacological Class:    Antihistamine
Pregnancy Category: C
Composition: Welfex 120
Each film coated tablet contains Fexofenadine HCl USP 120 mg
Each film-coated tablet contains Fexofenadine HCl USP 180 mg
COMPOSITION: Welfex Suspension
Each 5 ml contains Fexofenadine HCl USP 30 mg

What is Welfex?

Welfex contains Fexofenadine Hydrochloride 120/180 mg in tablet form and Fexofenadine Hydrochloride 30 mg/5 ml suspension. Fexofenadine is classified as a second-generation antihistamine pharmaceutical drug.


What is it used for?

  • Seasonal allergic rhinitis
  • Chronic urticaria


How does it work?

Welfex is an antihistamine used to relieve allergy symptoms such as watery eyes, runny nose, itching eyes/nose, sneezing, hives, and itching. It works by blocking a certain natural substance (histamine) that your body makes during an allergic reaction.


How to take Fexfenadine (Welfex)?

Always take Welfex exactly as your health professional has told you.



Adults and Children 12 Years and Older:  120 and 180 mg Welfex tablet once daily.

Children 2 to 11 Years: 30 mg (5ml) Welfex Suspension twice daily.

Pediatric 6 months to less than 2 years: 15 mg (2.5 mL) Welfex Suspension twice daily.


Take Welfex before a meal.  This medicine starts to relive your symptoms within 1 hour and lasts for 24 hours.


What if you miss a dose?

Take the medicine as soon as you can, but skip the missed dose if it is almost time for your next dose. Do not take two doses at one time. Remember to take the pack and any remaining tablets/suspension with you.


The most common signs of overdose are dizziness, drowsiness, fatigue and dry mouth.


What to do in case of overdose?

Contact your healthcare professional or go to the nearest hospital emergency unit immediately.


What do you need to know before you take Fexfenadine (Welfex)?


Do not take Welfex

If you are allergic to fexofenadine or any of the other ingredients of this medicine


Warnings and precautions

Talk to your healthcare professional before taking Welfex if you:

  • have problems with your liver or kidneys
  • are elderly
  • have heart problems, as fexofenadine, like other antihistamines may cause your heart to beat
  • faster (tachycardia) or you feel your heart beating (palpitations).


Pregnancy and breast-feeding

If you are pregnant or breast-feeding, think you may be pregnant or are planning to have a baby, ask your healthcare professional for advice before taking this medicine.


Do not take Welfex tablets if you are pregnant, unless necessary. Welfex tablets are not recommended during breast-feeding.

Driving and using machines

Welfex is unlikely to affect your ability to drive or operate machinery. However, you should check that these tablets do not make you feel sleepy or dizzy before driving or operating machinery.


What are the possible side effects?

Like all medicines, this medicine can cause side effects, although not everybody gets them. If you get any of the following symptoms after taking these tablets you should contact your healthcare professional immediately as these may be signs of a serious allergic reaction

  • Swelling of the face, lips, tongue or throat and difficulty breathing.


The following side effects have also been reported:

Common (may affect up to 1 in 10 people): headache, drowsiness, feeling sick (nausea), dizziness

Uncommon (may affect up to 1 in 100 people): tiredness or sleepiness

Not known (frequency cannot be estimated from the available data): difficulty sleeping (insomnia), sleeping disorders, bad dreams, nervousness, fast or irregular heartbeat, diarrhea, skin rash and itching, hives, serious allergic reaction which can cause swelling of the face, lips, tongue or throat, difficulty breathing


Mechanism of action:

Fexofenadine is a second-generation piperidine H1-antihistamine. H1-antihistamines interfere with the agonist action of histamine at the H1 receptor and are administered to attenuate inflammatory process in order to treat conditions such as allergic rhinitis, allergic conjunctivitis, and urticaria. Reducing the activity of the NF-κB immune response transcription factor through the phospholipase C and the phosphatidylinositol (PIP2) signalling pathways also decreases antigen presentation and the expression of pro-inflammatory cytokines, cell adhesion molecules, and chemotactic factors. Furthermore, lowering calcium ion concentration leads to increased mast cell stability which reduces further histamine release.


First-generation antihistamines readily cross the blood-brain barrier and cause sedation and other adverse central nervous system (CNS) effects (e.g. nervousness and insomnia).


Pharmacokinetic properties:

Absorption: Fexofenadine is rapidly absorbed following oral administration and its absolute bioavailability is approximately 33%. The Tmax following oral administration is approximately 1-3 hours.

Fexofenadine AUC is decreased by >20% when coadministered with fruit juices (e.g. apple, orange, grapefruit) due to their inhibition of OATP transporters – for this reason, prescribing information recommends administering fexofenadine only with water.8 Similarly, coadministration of fexofenadine with a high-fat meal appears to decrease AUC and Cmax by >20%

Protein binding: Fexofenadine is 60-70% bound to plasma proteins, primarily to albumin and α1-acid glycoprotein. The extent of protein binding is decreased to 56-68% and 56-75% in patients with renal and hepatic impairment, respectively.

Volume of distribution: The volume of distribution is approximately 5.4-5.8 L/kg.

Metabolism: Fexofenadine is very minimally metabolized, with only 5% of an ingested dose undergoing hepatic metabolism.10,7 The only identified metabolites are a methyl ester of fexofenadine (3.6% of the total dose) and MDL 4829 (1.5% of the total dose).9 The enzymes responsible for this metabolism have not been elucidated.

Excretion: Approximately 80% of an ingested dose is eliminated in the feces, likely largely unchanged due to fexofenadine’s limited metabolism, and 11% is eliminated in the urine.7 The principal pathways of fexofenadine elimination are biliary and renal.

Elimination Half-life: 11-15 hours

Clearance: The oral clearance of fexofenadine is approximately 50.6 L/h and the renal clearance is approximately 4.32 L/h.

Drug Interactions

Tell your healthcare professional if you are taking, have recently taken or might take any other medicine. This is especially important for the following medicines:

  • Erythromycin (an antibiotic)
  • Ketoconazole (a treatment for fungal infections)


Indigestion remedies containing aluminium and magnesium may affect the action of Fexofenadine by lowering the amount of medicinal product absorbed.

It is recommended that you leave about 2 hours between the time that you take Fexofenadine and your indigestion remedy..