Principium Psychiatry

A World-Class Team Ready To Help

Offering a variety of treatments suited to each individual’s needs including psychopharmacology, psychotherapy, TMS, Ketamine infusions, and electroconvulsive therapy. 

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Principium Psychiatry

An Innovative Psychiatric Clinic in NYC, Greenwich, CT, & Santa Monica, CA

Located in the heart of New York City, Principium Psychiatry strives to provide effective, individualized mental health treatment for patients with a wide range of psychiatric needs. No matter what symptoms or concerns bring you to our convenient midtown office, our staff of caring psychologists, psychiatrists and nurses will listen carefully, make you feel welcome and recommend the treatment options that are most likely to help you reach your goals.

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Psychiatry Services in the Heart of NYC, Greenwich, CT & Santa Monica, CA

At our clinic, we aim to bring all our patients effective and up-to-date treatments. In addition to traditional psychotherapy and psychopharmacology in NYC, we offer innovative depression treatments like Transcranial Magnetic Stimulation (TMS), IV ketamine, and intranasal ketamine (Spravato) therapy. Our psychiatrists in New York City also use genetic testing to ensure you receive medications compatible with your body’s unique biology.

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We use a variety of approaches to suit the individual needs of our clients. Our medical director Dr. Cohen and the rest of our team have experience treating mental health disorders using cognitive-behavioral therapy, psychodynamic psychotherapy, insight-oriented therapy, mindfulness and other evidence-based therapy styles.

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Psychopharmacology involves using medication to treat mental disorders. Our pharmacologists in Manhattan will work closely with you to find a medication that improves your symptoms while minimizing side effects. Patients seeking medication therapy typically visit us once per month or more frequently, as needed.

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Local patients who prefer to receive treatment from the comfort of their own homes can take advantage of our convenient telepsychiatry service. All you need to receive telepsychiatry is a computer with a webcam and a reliable Internet connection.

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Ketamine Therapy

In this pioneering treatment for depression and other mood disorders, patients receive a small dose of the anesthetic ketamine through an IV infusion. Each treatment takes approximately one hour. Because IV ketamine therapy is not yet approved by the U.S. Food and Drug Administration (FDA), it is typically recommended for patients with persistent symptoms that haven’t responded to other treatment options. Intranasal ketamine (Spravato) has FDA approval for the treatment of depression. For those who prefer intra-nasal to IV ketamine, we provide this treatment in the comfort of our office.

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Transcranial Magnetic Stimulation (TMS) treats major depression using a magnetic field to induce stimulation in targeted parts of the brain associated with depression, causing neurons (brain cells) to become more active. TMS is FDA-approved and recommended by the American Psychiatric Association. Treatment occurs over 4-6 weeks, with individual sessions ranging from 20 minutes to one hour in length. Patients stay awake during treatment and typically feel no discomfort and can immediately resume normal activities.

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meet our notable staff

World-Class Physicians

Dr. Ziv Cohen

MD Psychiatrist, Founder and Medical Director

Specialization: Psychiatrist


Daniel Santarsieri

MD Psychiatrist, Director of Clinical Services

Specialization: Psychiatrist


Tess Anderson

NP Psychiatric Nurse Practitioner

Specialization: Psychiatric Nurse Practitioner


Megan Cornillie

PA Psychiatric Physician Assistant

Anna Higgins

NP Psychiatric Nurse Practitioner


Dr. Joseph Houchins

NP Psychiatric Nurse Practitioner, Director of Clinical Operations

Specialization: Psychiatric and Mental Health


Rivka Moskowitz

NP Psychiatric Nurse Practitioner


Patrick Wester

NP Psychiatric Nurse Practitioner

Amy Barr

L-CAT Licensed Creative Arts Therapist

Specialization: Art Therapy, Psychotherapy


Warden Prescott

PhD LMSW Licensed Social Worker, Director of IOP


Dr. Reed Maxwell

PhD Clinical Psychologist

Specialization: Psychologist



Individualized Psychiatry Practice

Our world-class team at Principium Psychiatry offers traditional psychiatry and therapy treatment services along with interventional medicine. Our interventional treatments include Ketamine Therapy, TMS (Transcranial Magnetic Stimulation), ECT (Electroconvulsive Therapy) and IOP (Intensive Outpatient Programs). These treatments require advanced diagnostic criteria and are available for outpatient care. For insurance and billing information please contact us or call our office.


Interventional Treatments

At our clinic, we aim to bring all our patients effective and up-to-date treatments. In addition to traditional psychotherapy and psychopharmacology in NYC, we offer innovative depression treatments like Transcranial Magnetic Stimulation (TMS), IV ketamine, and intranasal ketamine (Spravato) therapy. Our psychiatrists in New York City also use genetic testing to ensure you receive medications compatible with your body’s unique biology.

By offering innovative psychiatric treatments, we can serve the widest range of patients possible, from those with mild but troublesome symptoms to those with severe and persistent symptoms who have struggled to find effective treatment in the past. We can provide care with or without medication or use a combination of strategies tailored to your needs. Our psychiatrists and psychologists take the time to consider all aspects of your situation and walk you through multiple treatment options, so you can make the best choice for you.

The services we offer at our psychiatric clinic in New York include:

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At Principium Psychiatry, we offer state of the art, cutting edge Electroconvulsive Therapy (ECT) for depression and other conditions. This treatment is provided in a private, state of the art treatment center on Park Avenue, where comfort, privacy, and safety are a priority. Principium Psychiatry’s team collaborates with a top tier anesthesia team to ensure that the treatment is comfortable and safe.

Ketamine is a cutting-edge psychiatric treatment being used to target severe medication and treatment resistant depression. Ketamine has been widely used as an anesthetic for minor procedures since the 1960s. In many countries, it is used by first aid response workers when dealing with minor trauma. The safety of Ketamine is such that it is used as outpatient anesthetic by non-physicians. The dose used to treat depression is about one quarter (1/4) of anesthetic dose.

The first line of treatment for depression and other mood disorders typically involves a combination of medication and talk therapy. This treatment strategy proves effective for many people. However, some patients may experience troublesome side effects or have persistent symptoms that fail to respond to treatment.

Every individual’s experience with depression is different, and as a result, experiences with depression treatments vary. At Principium Psychiatry, we believe everyone deserves access to the mental health care they need to feel better. That’s why, in addition to traditional psychotherapy and psychopharmacology, we offer innovative treatment options like Transcranial Magnetic Stimulation (TMS).

Intensive Outpatient Programs are structured mental health treatment programs designed to provide therapeutic support to individuals with mood and anxiety disorders. IOPs are distinct from inpatient programs because patients do not require 24/7 hospitalization. Instead, they attend regular therapy sessions, group counseling, and educational workshops while living at home or in supportive environments.


Aligned With Your Coverage

In addition to a familiar pay-per-appointment model, we offer a six-month concierge service, which takes care of prescription charges and gives you more flexible options for scheduling and rescheduling. Most of the treatments we provide for mood and anxiety disorders are covered by insurance, and although we are out-of-network, we will provide invoices you can submit to receive reimbursement. For TMS, we do accept medicare and work with most major insurances.

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Your out-of-network benefits will reimburse you for the cost of treatment. Call our office for further details.
our testimonials

What Our Patients Say

Dr. Cohen and his team are so fantastic! They did everything they could to make me feel comfortable, and I started feeling better after the first dose of Ketamine!

Verified Patient

The treatment was so much more comfortable than I thought it would be. I experienced slight discomfort during the first two treatments, but it was smooth sailing from then on!


The suite in which I received the treatment was comfortable and welcoming. I was able to relax during the treatments and each time I left, I felt more at peace.


Before starting TMS, I was so depressed that I couldn’t eat, sleep or get out of bed. I had stopped doing the things I enjoyed entirely, because I didn’t have the energy or interest. It took a few weeks, but I started to notice myself thinking more positively, and it kept improving from there. Thank you, Dr. Cohen!


I am so thankful to Dr. Cohen and his team! Thanks to them and the Ketamine treatment, I’m feeling better than I have in years. I was pleasantly surprised that there were no side effects.


My depression improved dramatically throughout the course of my TMS treatment. I am finally able to sleep through the night and I am looking forward to living my life again. My entire family noticed the difference in me before I did. TMS changed my life after decades of failed medications and terrible side effects. I finally feel like “me” again.


Ready to Get Started?

Please fill out the request form below and a team member will be in touch to confirm and schedule your appointment. Please allow 24 hours for us to confirm your appointment. Thank you!

We will confirm the appointment time upon booking completion and we strive to accommodate your ideal time selection. Based on availability we might need to schedule a different time from what is selected.

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    Thursday, March 24th 2022
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