Pregabalin is a novel isomer of gamma-aminobutyric acid that functions as a major inhibitory neurotransmitter in the brain. It is used daily in medical practice for treating neuropathic pain, fibromyalgia, generalized anxiety disorder, and partial seizures. Due to its antiglutamatergic effects, it poses a potential addiction risk. For example, an abrupt discontinuation of this substance may cause patients to exhibit physical withdrawal symptoms, such as insomnia, nausea, headache, and diarrhoea. However, there is no information in the literature that addresses whether the rapid discontinuation of pregabalin can cause psychosis to occur. Here we presented a 20-year-old patient with his first episode of psychosis that was likely attributable to his withdrawal from a high dosage pregabalin. He lacked physical signs of withdrawal; however, a psychiatric examination was conducted. It was determined that the patient was experiencing paranoid ideation, auditory hallucinations, and mutism. Furthermore, he had engaged in self-mutilative actions and had attempted suicide. Due to the short time frame between the rapid discontinuation of a relatively large dose of pregabalin and the onset of the patient’s first episode of psychosis, it is likely that the psychotic episode was triggered by the cessation of the medication. This is the first known case of psychosis that was caused by the rapid withdrawal of pregabalin to be discussed in the literature. The results of this clinical case may guide clinicians to recognize the symptoms of acute pregabalin withdrawal.