This case describes a 31-year-old female Caucasian patient with complaints of ongoing depression, agitation, and severe panic attacks. The patient was untreated until a recent unsuccessful trial of citalopram followed by venlafaxine which produced a partial response. Genetic testing was performed to assist in treatment decisions and revealed the patient to be heterozygous for polymorphisms in 5HT2C, ANK3, and MTHFR and homozygous for a polymorphism in SLC6A4 and the low activity (Met/Met) COMT allele. In response to genetic results and clinical presentation, venlafaxine was maintained and lamotrigine was added leading to remission of agitation and depression. 1. Introduction Patient treatment has traditionally been applied in a “one-size fits all” fashion. Most prescriptions have been standardized to target a particular illness or symptom which allows for minimal interindividual variation in treatment response. This becomes critical when treating psychiatric illnesses, as many prescribed medications are not effective in certain individuals or can have serious adverse effects. Information gathered from genetic testing can allow clinicians to predict a patient’s propensity for medication response and risk for adverse drug reactions. Utilizing this information, a treatment plan can be customized to the patient to improve treatment outcomes [1]. 2. Case The patient, a 31-year-old female Caucasian with a long history of depression starting in her early teens, presented to a psychiatric nurse practitioner (PNP) with a chief complaint of incessant crying and worsening agitation. She reported symptoms of severe anergia, slow thought processes, short-term memory problems, and forgetfulness, all of which impacted daily activities, but she denied sleep disturbances. She reported multiple crying spells daily and admitted ongoing isolative behaviors. She also reported agitation leading to daily panic attacks but displayed no manic symptoms or psychosis. Her depression began in her midteens with progressively worsening of symptoms since that time. The patient’s psychiatric symptoms were managed solely by her primary care physician (PCP) who referred her to a PNP several times over the course of a year before the patient finally consented to be seen by a specialist. Although no official diagnosis was made prior to this visit, after seeing the PNP, she was diagnosed with major depressive disorder, recurrent and moderate (ICD-9 296.32/ICD-10 F33.1), with no presenting comorbidities. She has had no previous outpatient or inpatient treatment and denied suicidal ideation
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