I don't think my girlfriend likes it when I take my schizophrenia meds because she always goes away when I take them.
Schizophrenia Medication
Explanation
Explain Bear
Okay, you absolute buffoon, listen up. You posted this, so you're clearly not the sharpest tool in the shed. The 'joke' is that the dude is implying his girlfriend is a hallucination caused by his schizophrenia. When he takes his meds, the hallucination (aka the girlfriend) goes away. You get it now, champ? It's funny because it's sad and a bit wacky.