Some Video Testimonials

Disclaimer * We provide testimonials to help you gain confidence about how we work and results we achieve – please remember that results may vary from person to person.


weight loss hypnosis
“I learnt how to lose weight and keep it off. Now let me teach you”. D4 Clinic psychologist Jason O’Callaghan 

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Before & After Photos


“Hi Jason, how you doing. I am going great since we last spoke, down just 2 stone and finding I feel much better and have a lot more energy each day. Walking daily and listening to my stomach has made a lot of difference. My friend Kelly was recently in with you also after I told here about you and she is nearly down a stone already. So both of us are looking forward to a nice shopping spree soon. Thanks so much”
- Flo

Dublin 6

“Hi Jason, just a note to thank you for the sessions. I am now on week 10 since I came to you first and am down just over 2.5 stone and am so happy with upcoming wedding that I can fit into the dress size I wanted to. See you again soon for another visit.”
- Mary B


Dear Jason,

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.

- Breda Keating

“Still going great and weighed this week 10-12 pounds more gone and feeling good, not weighing weekly so nice to see big jump. Hope to see you in Sept. probably with an interested friend will be in touch.”
- Lavinia

“Just a quick email to thank you for the recent sessions, I did four in total and found with each one I was able to relax more and more. My weight loss is going well and I am down 44 lbs in 3 months. Exercise is going well and food intake is right down. I still have a few more stone to go but the road ahead is looking good. I will be in touch to book another session when I get back from my break.”
- Maureen N


“I have lost over 3 stone with thanks to the hypnotherapy gastric band operation, I just wanted to thank you for all your help. I feel like a different person now. My diet and lifestyle has changed and I am a much happier person. Thanks again.”
- Anne C


Thanks all. Should have got the hypnosis done years ago. Flight was quite pleasant and hopefully will be the same on way back. Just shows the power of the mind. Thanks to d4 clinic and Jason O’Callaghan for making it happen for me. I would recommend a visit to Jason for anyone suffering a phobia to get it sorted once and for all.

Valerie Wallace