I have two cats and both caught a nasty upper respiratory infection, which also developed into conjunctivitis. I tried ACV for four days, as prescribed by many, but nothing worked. If anything, they were only getting worse. So after reading other sites and recalling some herbal advice from our parents, my boyfriend and I decided to create a different treatment. We decided to give them some Echinacea and Vitamin C. They were not eating or moving because they were so sick. So we also bought some wet food that had a TON of juice (and barely any meat), used an eye dropper and force fed them the juice supplements. On the first night, for each cat we used half a capsule of Echinacea, half a tablet of Vitamin C, and mixed it with wet food juice. The effect was immediate! I saw a change in their behavior the following morning. They moved very little but it was a significant change. It was so significant, in fact, I felt motivated to do a little more research and found that L-Lysine might be helpful too. So we bought that the same morning and determined that for each cat (they are both close to 6 months) we would add a full capsule of Echinacea, with a full tablet of L-Lysine to two of their meals. The third meal would consist of half a capsule of Echinacea and half a capsule of Vitamin C. By the second night they were already eating on their own. They seemed to have a hard time swallowing so we bought more of the "soupy" wet food, which encouraged them to eat--they didn't even mind the supplements in them. Also, on the first night my boyfriend bought an over-the-counter homeopathic pink eye solution for them. We gave them, that first night, one drop in each eye (we were too scared to do more). One of my cats had excessively watery eyes; the other cat had obvious and strong symptoms of conjunctivitis--he couldn't even open his infected eye. Since then, we've been giving them about 2 to 3 drops daily throughout the day. Well, it's officially the 7th night of their treatment and they are almost entirely healed. They only have the remnants of sneezing. My cat with the excessively watery eyes doesn't have them anymore and my cat with the strong case of conjunctivitis is almost cured as well. We've check his eyes by spreading them gently while applying the drops and now there is barely any swelling and redness--his eyes look very healthy! They are FULL of energy, running around and playing. They are acting as if they were never sick! I am so surprised this natural treatment worked at all. I didn't expect to see such immediate results. I truly believe that it was the Echinacea and L-Lysine that helped them, but it's hard to tell since we included the Vitamin C and the pink eye solution to their treatment. Anyway, I thought I'd post my case on here in case anyone finds themselves in the same situation. I was desperate and scared out of my wits for my cats. When I first read the posts on this website, I was excited to find so many ACV success stories. Unfortunately for me, they did not work for my cats. But I'm happy this treatment is working for them. I haven't had any side effects yet. I'll continue the treatment and post another update soon.