Purevax RCP (vaccine against feline viral rhinotracheitis, feline calicivirosis and feline panleucopenia) is used to protect cats against three highly contagious and potentially life-threatening diseases: feline viral rhinotracheitis, calicivirus, and panleukopenia. These diseases can cause respiratory, oral, and gastrointestinal issues, and the vaccine helps prevent or reduce the severity of these illnesses.