Zanamivir is mainly used to treat various forms of influenza in patients over the ages of seven. It is mainly prescribed in cases where symptoms of influenza last for more than two days.  Zanamivir can also be used to prevent influenza in children under the ages of 5.


What is Zanamivir?

Zanamivir is an antiviral drug. It works by stopping the growth and spread of the viruses that attack the respiratory system. Its mechanism of action works by inhibiting viral proteins and consequently altering the ability of the virus from spreading.


How should Zanamivir be taken?

Zanamivir is administered in the form of powder to be taken in an intranasal manner.


Side effects associated with Zanamivir

Among the possible side effects of Zanamivir include the following:


  • Cough
  • Diarrhea
  • Dizziness
  • Headache
  • Nausea
  • Sinusitis
  • Sore throat
  • Stuffy nose
  • Vomiting


It is important to contact a doctor immediately if you experience:


  • Rash
  • Urticaria
  • Difficulty breathing
  • Tightness in the chest
  • Swelling of the mouth, face, lips, or tongue
  • Confusion
  • Hallucinations
  • Irregular heartbeat
  • Mood swings
  • Red, swollen or peeling skin
  • Convulsions
  • Shortness of breath
  • Persistent fever, chills, sore throat and other symptoms of an ongoing infection
  • Difficulty swallowing
  • Wheezing


Contraindications and warnings associated with the use of Zanamivir

Zanamivir may impair the ability to drive or operate hazardous machinery. This side effect can be aggravated by alcohol or certain medications. Any bronchodilators should be taken before taking zanamivir.


Before starting treatment with Zanamivir, it is important to tell your doctor if:


  • You have any allergies to the active substance, its excipients or any other drugs or food (particularly lactose or milk protein)
  • You are taking any other medications, herbal remedies or supplements. Mentioning in particular:  Live flu vaccines (to be taken in an intranasal manner) and bronchodilators
  • You are suffering (or have suffered) from cardiac, pulmonary, respiratory, psychiatric or psychological disorders
  • You are pregnant or breastfeeding


It is important to inform doctors, surgeons and dentists of any ongoing treatment with zanamivir.