The music of "Rx (Medicate)" contains an acoustic guitar riff, a distinctive whistling tune performed by Connolly, the sound of strings in the background, and elements of country music. Classic Rock called the track "an atmospheric piece of acoustic pop-rock", and Billboard and Loudwire both said it leans more towards the pop genre rather than the band's usual hard-rock sound. This has been attributed to Connolly's learning to play the piano, which he said forced him to write music differently. He rejected the notion that he was abandoning rock and said the song's change of musical direction had occurred naturally.
