Oseltamivir and zanamivir uses and toxicity

Oseltamivir is a prodrug used orally, activated in the gut and the liver. Zanamivir is administered intranasally. Both drugs decrease the time to alleviation of influenza symptoms and are more effective if used within 24 h after onset of symptoms. Taken prophylactically, oseltamivir significantly decreases the incidence of influenza. GI symptoms may occur with oseltamivir; zanamivir may cause cough and throat discomfort and has induced bronchospasm in asthmatic patients.