I have often used/recommended a blend of herbs for treating conjunctivitis, and it works brilliantly. I combine chamomile flowers, lavender flowers, eyebright herb and fennel seeds, at a ratio of 2:2:2:1. You use a heaped teaspoon in a cup, cover with freshly boiled water, and infuse for 10 minutes with a lid on. Strain well, and keep in the fridge (it lasts a couple of days). Dip a cotton ball or pad into the chilled infusion, and place over the eyes. Try to apply 3 - 4 times a day. This is really soothing, has anti-viral, anti-inflammatory, anti-bacterial and astringent qualities.

And try to use certified organic herbs if possible. If you can't obtain all the herbs listed above, organic chamomile teabags work quite well too - dip in boiled water, and allow to cool before placing over the eyes.