On September 13, 2013, Paulino was acquired by the Houston Astros as a player to be named later in an earlier trade for José Veras.[2] Paulino made his debut in the Astros organization in 2015 with the Tri-City ValleyCats and also played for the Quad Cities River Bandits and Lancaster JetHawks.[3] The Astros added him to their 40-man roster after the season.[4] Paulino was promoted to the major leagues on September 6, 2016.
On July 1, 2017, Paulino was suspended 80 games without pay for testing positive for a performance enhancing substance.[5] From that point on, he would not play again for the rest of 2017, but finished with a 2–0 record and a 6.52 ERA in six starts.[6]
Toronto Blue Jays
On July 30, 2018, the Astros traded Paulino, Ken Giles, and Héctor Pérez to the Toronto Blue Jays for Roberto Osuna.[7] The Blue Jays activated Paulino from the disabled list on September 5.[8] Paulino was designated for assignment on August 7, 2019.[9] He was released on August 10.
Philadelphia Phillies
On January 18, 2021, Paulino signed a minor league contract with the Philadelphia Phillies organization and was invited to Spring Training.[10] He was assigned to the Triple-A Lehigh Valley IronPigs to start the season. After posting a 4.35 ERA with 58 strikeouts in 25 appearances with Triple-A Lehigh Valley, Paulino's contract was selected by the Phillies.[11] He made his Phillies debut on August 13, pitching 2 innings and giving up 2 runs. The following day, he was designated for assignment.[12] He was outrighted to Lehigh Valley on August 16.