I too agree with the above from Trapper! Theres many factors to making good Colloidal Silver but simple things like using salt etc can do the opposite and create a heap of problems etc.
Theres a theory that Selenium and Vitamin E will help this condition. This is because the Silver adheres to the Selenium which is eventually washed out using the Vitamin E! You should take 200mcg (MICROgrams) of Selenium to 800-1200IU of Vitamin E. She should start the vitamin E at 200IU for the first week then add 200 the next week till you hit the right level. Some people cannot take Vitamin E in high strength straight away so build up.
Who knows how long it make take if at all but this is a good method. I presume chelation should help and try the number #1 Glucronic Acid found in good Kombucha.