A reference to the Bible passage Matthew 7:14 where Jesus says that in order to get to heaven you must walk a straight and narrow path (behave well). Cops are supposed to “behave well” or walk the straight and narrow path, but in this case they don’t.
Again the writer is implying that he is walking a straight and narrow path, but receiving hell in his life and he emphasizes this contradiction by creating a kind of oxymoron in this line.

The medicine, his mind, and his doctors should all be helping this stop, not encouraging it.

He is asking himself a rhetorical question here. Society often looks down on people with mental illness, thinking that if you take an anti-depressant or other psychiatric drug you are simply weak or giving up. The line can also remain ambiguous to suggest that anyone doing any kind of drug may not be “tough enough” to engage with life.

In his paranoia the writer feels that both his governing psyche and the medical institutions that are supposed to be assisting him are just setting him up to feel even more pain. So even though he’s taking medication, that he does not want to take, in order to help himself, its eventually going to wind up causing him suffering and he will feel that it isn’t his fault.

Also there is a tie in to the cliche “you reap what you sow” which is commonly used to tell people that they get what they deserve. In this case he feels it is a false statement because he is not getting what he deserves, he’s been set up.

Half-ass sarcastic or partially sardonic commands and suggestions that tell a person what they can do to feel better.

The grab-bag of mantras is showing that this person has heard so many mantras over time that do and don not work, so randomly choosing one may or may not help him find comfort.

A kleptocrat is a ruler or governing body that steals off of the nation that it is ruling over. Here it is again a reference to the corruption of the part of one’s mind that should be maintaining order inside of that person’s psyche. Since whatever it is that is ruling his mind is a “corrupt official” it can be bribed. In this case the writer is bribing his mind with medication in order to achieve some type of comfort.

These relationships represent hyper-exaggeration that occurs when one’s mind is diluted with fear. The palpitation actually being a citing of a common symptom of panic attacks that are often mistaken for heart attacks by the people having them.

He feels that the medication he is taking to ease his struggles may actually be harming him, or the DEA (In this case a metaphor for the psychiatry industry, a reference to the Karma Police as an enforcement agency that is supposed to be regulating people’s moods and experiences fairly), which is supposed to be assisting the community, by preventing certain drug use, is actually harming him by having this medication available and suggesting he use it, like an assassin bug, also known as a kissing bug, does by injecting a substance into its victim in order to deteriorate its insides, then eat it.

He thought he had faced is problems and gotten rid of them, but maybe he just ignored them or denied them in some way.

Reference to a line sung in the Radiohead song “Karma Police.