Formication and delusion of persecution, both are together seen in
High-Yield Explanation
The complications of chronic cocaine use include acute anxiety reaction, uncontrolled compulsive behaviour, psychotic episodes (with persecutory delusions, and tactile and other hallucinations), delirium and delusional disorder. Formication is tactile hallucination of bugs crawling. Ref: Sho textbook of Psychiatry by Niraj Ahuja, 7th editon, page 47.