Mental illness refers to a medical condition that negatively affects individual’s thinking, feeling, mood, ability to relate to the others as well as his/her daily activities (National Alliance on Mental Illness, 2013). The various types of mental illnesses include depression, schizophrenia, bipolar disorder, obsessive-compulsive disorder (OCD), anxiety and borderline personality disorder and post-traumatic stress disorder (PTSD) (National Alliance on Mental Illness, 2013). This research analyzes the experience and influence of mental illness diagnosis on a patient. (Caplan & Cosgrove, 2004) Mental illness diagnosis is the process of correcting and curing the mental disorders which are experienced by patients. The effects of a mental illness diagnosis are several. The first effect is violence; many patients, when suffering from some condition, do not take it well and often exhibit resistance when diagnosed with mental illness (Brooker & Repper, 2009). Exposure to violence contributes to higher levels of stress. Hence they use tobacco to curb the stress, which in turn leads to heart diseases and cancer, and this may become very detrimental to the patient. The second effect of mental illness diagnosis is psychosis; this refers to the experience of a patient to lose contact with the aspects of reality (National Alliance on Mental Illness, 2013). Psychosis may be transient, intermittent, short term, or long term psychiatric condition (Caplan & Cosgrove, 2004). In the event of a patient experiencing psychosis, it becomes a very challenging time for the family of the patient. The third effect is trauma; this is whereby the patient is suffering and as a result, becomes overwhelmed with the situation. Trauma causes a lot of pain to the patient, and it takes the collective efforts of friends and family to address this problem. The last effect of mental illness diagnosis is the borderline personality. Analyzing the mental illness diagnosis, it should be noted that the first experience is a misdiagnosis and inappropriate mental health treatment. This has adverse results on a patient as they cause self-destructive behaviors. The patient can resolve to drug and alcohol abuse, and in turn, this may lead to the patient being violent (Porter, 2012). Secondly, when a doctor diagnoses mental illness properly, the diagnosis must be done since a wrong diagnosis can lead to other long term effects. Physical diagnosis is usually performed through interviews and lab tests. Also, the diagnostic approach that many doctors may use to diagnose mental illness is referred to as MINT, which refers to Metabolic, Infectious, Neurologic, Traumatic model. Considering the four steps, in the metabolic phase, the doctor ascertains if a patient has taken drugs and if a toxicology screen test has been performed. The physician also tries to find out whether the patient has taken steroids or amphetamines or is trying to refrain from taking alcohol (Brooker & Repper, 2009). In the Infectious phase, the doctor tries to find out if there is an infectious process like, for example, Lyme disease or meningitis that could be related to psychosis. The Neurological phase is where it is ascertained if a neurologic condition is present. The doctor tries to find out if it is a neurological condition that is causing the symptoms exp