JASON O'CALLAGHAN
D4 Psychology & Hypnotherapy Clinic
(Hypnotherapy, Counselling, Mindfullness and CBT)
The D4 Clinic provides a complete range of hypnotherapy services, from in-clinic sessions and online appointments to VIP intensives and instant-access downloadable programmes, ensuring there’s an approach to suit every individual.
Open daily from 9am to 8pm. Same day appointments available.
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About Jason O'Callaghan
Hello, I'm Jason O'Callaghan.
Member of the Psychology Society of Ireland
M.Ps.S.I. (Membership No M13886)
Since 2012, I’ve helped thousands of people across Ireland create lasting change through evidence-based clinical hypnotherapy, psychology, counselling, CBT, and mindfulness.
If you’re looking for a trusted hypnotherapist to help with anxiety, stress, confidence, or unwanted habits, you’re in the right place. Many clients come to us feeling stuck or overwhelmed, and leave with clarity, calm, and renewed control.
At the D4 clinic our programs mixing clinical hypnotherapy, counselling, CBT and mindfulness to focus on real transformation by addressing the root causes behind what’s holding you back. You can work with us in person at our Blackrock clinic, through personalised hypnotherapy audio programmes, or via downloadable bundles you can use anytime.
My research in clinical hypnotherapy has been published by the Mayo Clinic in the United States. In 2013 I was named on the Trinity College role of honour for my work using therapy with cancer patients. I hold a honours degree in psychology plus a masters degree in applied psychology from Trinity College Dublin. I also hold qualifications from Maynooth University in counselling and the IICP in Dublin in CBT. I also hold national diploma in media and spent 10 years working within the Irish media at the highest level. I have appeared as an expert on ITV’s This Morning, 2FM, Newstalk, and TG4, as well as speaking at major international hypnotherapy conferences.
If you’re ready to make a positive change with a proven hypnotherapist, get in touch with The D4 Clinic today and begin your path to a calmer, more confident life.
Together, we can create the change you’re ready for so you can feel calmer, clearer and more in control.
What I can do for you
- Help you reduce anxiety, manage stress and feel more in control through personalised clinical hypnotherapy and psychological techniques
- Break unwanted habits such as overeating, smoking, vaping or negative thinking patterns with structured, evidence-based strategies
- Improve confidence, focus, sleep and emotional wellbeing using an approach grounded in psychology, CBT, mindfulness and counselling
- Provide VIP intensive sessions for clients who want deeper support or faster results
- Give you clear, practical tools you can use every day to stay calmer, more resilient and more motivated
- Offer flexible options that fit your lifestyle including in-clinic sessions, personalised hypnotherapy audio programmes and downloadable bundles
- Bring over a decade of experience, Mayo Clinic-published research and specialist training from Trinity College Dublin to help you make meaningful and lasting change
Although hypnotherapy results cannot be guaranteed, you can rely on my clinical experience, professionalism and commitment to helping you achieve the best possible outcome.
Latest Reviews from Google
Our Treatments
Anxiety Hypnotherapy
Blushing Hypnotherapy
Break Your Relationship with Food Hypnotherapy
Claustrophobia Hypnotherapy
Deep Sleep Hypnotherapy
Dentist Visit Anxiety Hypnotherapy
Fear of Clowns Hypnotherapy
Fear of Flying Hypnotherapy
Gambling Addiction Hypnotherapy
Instant Confidence Hypnotherapy
Junk Food Addiction Hypnotherapy
Nail Biting Hypnotherapy
Nicotine Gum Dependency Hypnotherapy
Procrastination Hypnotherapy
Public Speaking Hypnotherapy
Reduce Alcohol Habit Hypnotherapy
Social Anxiety Hypnotherapy
Stop Vaping Hypnotherapy
Stress and Anxiety Hypnotherapy
Sugar Dependancy Hypnotherapy
Success Stories
Many thanks for your help at D4 clinic. I have now lost over 3 stone and feel so good. This picture of me is in my first pair of size 12 jeans in over 20 years. It is just amazing how it has worked. I now love my daily walk.Thanks again for all your help. I would have no hesitation in recommending the D4 CLINIC to my friends and colleagues.
