According to Dr. James Balch, M.D., author of the bestselling book Prescriptions for Nutritional Healing, you can indeed use colloidal silver directly in your eyes for Pink Eye and other eye infections. In his newsletter, he recommended a few drops in each eye, several times a day, of 5 ppm to 10 ppm colloidal silver.
When our son Ron was sent home from school with Pink Eye, the school nurse called to tell us it was a particularly virulent strain and was going around the school. She asked us to keep him home for several days. We started putting a few drops of colloidal silver into each eye periodically throughout the afternoon, and by the next day it was completely cleared up and he was back to school. The school nurse called asking us what in the world we had done, because she had never seen a case that bad clear up that quickly.
We have also used it for healing strep throat (just gargle with colloidal silver four or five times a day), stomach infections including food poisoning (I drank several ounces of 10 ppm every hour for four hours, and it stopped the vomiting and nausea in its tracks) and even colds, flus and many other types of infections.
We even give it to our pets in their water bowls, whenever they get sick. Our cat absolutely loves it, and in fact, prefers drinking colloidal silver to water. An interesting animal lover's web site called Bender Place also recommends giving cats and other pets colloidal silver, rather than risking potentially dangerous vaccinations which often harm pets. (See http://www.benderplace.com/allcreatu...pet_health.htm
As for the problem is different brands having different strengths and different types of measurements, this is one good reason why you should always make your own colloidal silver. That way, you always know you are getting pure colloidal silver with no additivies, and you personally control the strength.
Colloidal silver can be prepared easily with a simply device called a colloidal silver generator. You can read all about them at www.thesilveredge.com
There is even a written primer on the use of colloidal silver for beginners, quotes about colloidal silver usage and safety from medical doctors and other experts, a short two-minute video showing how to make colloidal silver with a home colloidal silver generator, and much more.