Does Toppik (Hair Fiber/ Hair concealer) cause hair loss if used daily?

I am not aware of any scientific data suggesting that fibers can cause hair loss nor have I actually seen this in one of my patients.

There is no evidence this will increase hair loss. I suggest seeing a hair loss expert now to go over your condition and provide you information about your best treatment options. There are great non-invasive options like prp/progesterone and/or hair transplantation. See an expert. Best, Dr. Emer

Toppik does no cause hair loss any more than sawdust would. The pores of the scalp are not the source of hair loss and blocking them is not a factor  (although Toppik does not block the pores anyway). The hair receives its nutrition from the blood supply at the hair bulb. If your hair is still thinning despite your treatment regimen, you should consider LLLT and PRP. 

The product Toppik should not affect your hair loss. Unlike what you may hear on the internet, the pores of scalp are not doing much to the growth and loss of hair. Scalp and hair receive nutrients and oxygen from your blood circulation. Even if you have a hair transplant procedure, you can resume using Toppik after the first 5 days.
It is good to have a medical evaluation including a microscopic evaluation of scalp and hair before continuing your medication if you have not done those to start with. Miniaturization study can predict you future hair loss and whether you need to be on both those medication or not. 

We have absolutely no proof that the product Toppix aids in the hair loss process.  The patients who use it are very happy with their temporary results. The only problem is that if you wash your hair, sweat or get caught in the rain, Toppix washes away. However it works extremely well for temporary situations.