Hello - I am sorry to hear how desperate you are - this sounds as though it affects you r life a great deal - have you any other information you can give -  importantly what was happening in your life when it started? - becaus e it is easier to treat and will have a lasting effect if the cause can be treated - the breath retraining? will help you control the symptoms but i should think it would be good to feel more at ease in life generally - so that this does not hang over you all the time - as something that may suddenly come on - homeopathic remedies can help  hugely with your problem - if you can let me know what was happening when it started or how you were feeling we can probably  find a remedy to help you  - you see distressing symptoms like yours are an external reflection of what is happening inside you - and a reflection maybe of your level of stress, upset or anxiety - I hope this makes some kind of sense and is of some help.