Easy Four 0.5Ml Vaccine is used for the active immunization of infants of the age of 6 weeks and above against Diphtheria, pertussis (whooping cough), Tetanus, and Haemophilus Influenzae type b infection. It contains Diphtheria toxoid, Tetanus toxoid, pertussis toxoid and Haemophilus type b conjugate vaccine. This vaccine works by stimulating the immune system to develop antibodies and antitoxins to fight against these diseases. It may cause mild side effects such as redness at the injection site, tenderness, irritability, vomiting, loss of appetite, and fever. Inform your doctor beforehand if you or your child has a history of severe allergic reactions to vaccines, currently taking other medication, or has any relevant vaccination history or medical conditions.