Serious adverse reaction is an adverse reaction of the body to the use of a medicinal product which has caused death, congenital anomalies or malformation, or posing a threat to life, requiring hospitalization, or which has caused permanent incapacity to work and (or) disability

Source: Russian Federation Law №61-FZ March 24, 2010 "On Circulation of Medicines"

Serious adverse reaction: An adverse reaction which results in death, is life-threatening, requires inpatient hospitalisation or prolongation of existing hospitalisation, results in persistent or significant disability or incapacity, or is a congenital anomaly/birth defect.

Source: Directive 2001/83/EC of the European Parliament and of the Council of 6 November 2001 on the Community code relating to medicinal products for human use