Global soccer governing body FIFA reduced the ban to six months but the World Anti-Doping Agency asked the Switzerland-based Court of Arbitration for Sport to increase the sentence to between one and two years.
The striker, who has protested his innocence throughout, appeared at a CAS hearing earlier this month.
The Peruvian Football Federation said on its Twitter site that it would travel to Brazil "to visit our selected Paolo Guerrero", and take photos and kit measurements for the World Cup.
Guerrero, 34, returned to professional football with Brazilian side Flamengo last week.
Peru, who have qualified for the World Cup for the first time since 1982, will face Australia, Denmark and France in Group C at the finals in Russia.
Guerrero has scored 32 goals for his country and helped them finish third in the 2011 and 2015 Copa Americas when he was leading scorer in both tournaments.
(Reporting by Ian Ransom in Melbourne; Editing by Peter Rutherford)
