A brother of mine struggles with serious mental illness. For at least the past fifteen years, he's been subject to various hallucinations (auditory more often than visual, but he says he experiences both) and paranoid delusions, plus a number of just-plain-weird non-paranoid delusions.
Currently he's focused on the FBI, which he believes is following him around, sabotaging his chances at getting a passport, and causing panic attacks, memory issues, stomach upset, sleep loss, etc. via remote-control electrodes implanted in his brain, chest and abdomen. He's also pretty worried they're going to assassinate him.
Where's he getting these ideas?
Well, it's online. You can find any information online, whether it's true or not.
Well, here's what his symptoms sound like to me. I think he's both really unhappy about his socioeconomic status and reacting, badly, to the last dose of medication wearing off. But you can't say that to someone who's convinced it's the FBI stalking him with an electronic voodoo doll.
Among the factors that make this really, really fucking ironic and annoying: there were, in fact, experiments that involved implanting electrodes into people's brains to control their behavior; deep brain stimulation devices and cardiac pacemakers are a reality; and the federal government (or at least the Presidential administration) does have the authority to arbitrarily determine any individual to be an enemy of the United States of America and have him detained or killed.
But anyway, bro wants to go to a doctor and get referred to a radiologist to get CAT or MRI scans taken in order to find the implanted devices. If he's told "no", he'll either stop going to see doctors or he'll try to find another.
What the hell are you supposed to say to this, other than "I'm sorry you feel bad"? Confronting delusions seems fairly futile to me.