The speaker describes watching television as a kind of medication. Instead of pills, the "antidepressants" come in through the eyes, and the speaker swallows whatever is on screen, even when they know it's full of lies. The title, "Purposefully Ignorant," suggests this is a choice: the speaker doesn't care about the ads or the deceit, because the screen calms the mind and that is enough. The closing joke, that even medicine has been "computerised," sounds casual, but it carries a sour edge. Comfort has become something manufactured and delivered by a machine.
The mood is flat, wry and a little sad. The rhyme on "-ise" gives the lines a bouncy, shrugging rhythm, as if the speaker is making light of something that isn't really funny. Then the last line, "The sky can be really blue sometimes...", changes the tone. The trailing dots make it sound wistful, as though the speaker has glanced away from the screen and remembered what they're missing.