I wrote an email to Vielight as follows
"I have used you device vielight gamma for more than 2 months . It didn't improve my symptoms of Parkinson rather it got worse.
please advise whether I should continue using it or stop it?"
Their reply was
"Your Parkinson’s (PD) may have become even worse if you had not used the Vielight Gamma. We have a good number of improvements with the disease using the Gamma, and a proper clinical study is being planned. It has already been tested safe and in the worst case may do little but it should not be contributing to making the condition worse.
We have an accessory to add to the Gamma for PD patients called the Neuro Plus-X priced at $750. It triangulates with the Neuro Gamma to reach the deeper regions of the brain associated with the PD. If you are interested we will let you now when it is available.
However, it I up to you as to what is comfortable for you to do, and we are always prepared to do the 80% refund as agreed.
Thank you for using our product."