The forward has missed Miami's last four games due to a muscle problem sustained last month.
Messi earned Argentina victory in their opening qualifier against Ecuador with a goal from a free kick, but did not play in the second game against Bolivia.
The 34-man squad named by coach Lionel Scaloni (45) did not feature the injured Angel Di Maria (35) but fit-again Paulo Dybala (29) was included.
Argentina host Paraguay at the Monumental Stadium in Buenos Aires on October 12th before facing Peru at the National Stadium in Lima.
Argentina Squad
Goalkeepers: Juan Musso (Atalanta), Emiliano Martinez (Aston Villa), Walter Benitez (PSV) and Franco Armani (River Plate).
Defenders: Nahuel Molina (Atletico Madrid), German Pezzella (Betis), Gonzalo Montiel (Nottingham Forest), Juan Foyth (Villarreal), Cristian Romero (Tottenham), Nicolas Tagliafico (Olympique Lyon), Nicolas Otamendi (Benfica) and Lucas Esquivel (Athletico Paranaense), Lucas Martinez Quarta (Fiorentina), Marco Pellegrino (Milan) and Marcos Acuna (Sevilla).
Midfielders: Leandro Paredes (Roma), Rodrigo De Paul (Atletico de Madrid), Guido Rodriguez (Betis), Facundo Buonanotte (Brighton), Enzo Fernandez (Chelsea), Alexis Mac Allister (Liverpool), Exequiel Palacios (Bayern Leverkusen), Bruno Zapelli (Athletico Paranaense) and Giovani Lo Celso (Tottenham).
Forward: Lucas Beltran (Fiorentina), Nicolas Gonzalez (Fiorentina), Lautaro Martinez (Inter Milan), Julian Alvarez (Manchester City), Alejandro Garnacho (Manchester United), Lionel Messi (Inter Miami), Carlos Alcaraz (Southampton, England), Thiago Almada (Atlanta United), Paulo Dybala (Roma), Facundo Farias (Inter Miami) and Lucas Ocampos (Sevilla).
