Medeiros signed a minor-league contract with the Angels on Tuesday.
Medeiros was added to the White Sox's 60-man roster Monday, James Fegan of The Athletic reports.
Medeiros cleared waivers and was outrighted to Triple-A Charlotte, James Fegan of The Athletic reports.
Medeiros was designated for assignment by the White Sox on Thursday.
Medeiros was optioned to Double-A Birmingham.
Medeiros had his contract purchased from Double-A Birmingham on Tuesday.
Medeiros is 2-0 with a 1.42 ERA, 1.11 WHIP and 18:12 K:BB in 19 innings over four outings with Double-A Biloxi this season.
Medeiros, 21, has a 5.27 ERA and 58:21 K:BB through 56.1 innings for High-A Carolina.
Medeiros allowed one earned run over five innings in a start with High-A Brevard County on Monday.
Medeiros is off to a rough start in his first go-around at the High-A level, posting a 9.19 ERA and 2.36 WHIP over his first four starts.