I doubt many people are buying this for their pets, but for anyone who is considering it, here is my story. My 19-year-old toy poodle came down with pneumonia. I took her to a vet with an ICU on Friday asking if she could stay with them as an inpatient until Monday morning. As of 8 PM Friday night, the vet thought my dog had at best a 50-50 chance of surviving until Monday morning, even with ICU care. Finally I made the decision to let her come home and die surrounded by family, in her own bed. We also discussed renting an oxygen tent for the home or purchasing a portable oxygen provider for dogs, but the vet thought the dog would likely be dead before either of those arrived. Dogs make their own vitamin C internally and normally do not need any supplementation, but in acute, emergency cases, some claim it can help if given in massive doses. Having nothing to lose, as she had a high likelihood of dying anyway, I gave her 1 packet of this every 2 hours. By the 5th packet she reached "bowel tolerance"-- meaning, she had reached saturation, causing diarrhea to begin. (She is 3.2 kg, which is 7 lbs.) By that time she was clearly and obviously breathing easier. I then fell asleep and woke up 4 hours later (5 hours after she received the 5th packet). By that time, she had fallen back into labored breathing again. Again, I gave her 1 packet every two hours until she had diarrhea again, and again her breathing improved. The improvement was marked and very obvious. We repeated this for two days. By the end of the weekend, she was very obviously "out of the woods" and although she was still very, very sick, I could see she was going to survive. Twelve days later, she is now walking around the yard and enjoying the spring. The vet says it is a "miracle." The dog herself acts like nothing whatsoever has happened. To be clear, she was also receiving subcutaneous fluids once a day (which I administered to her at home) to keep her from getting dehydrated, and I also used a vaporizer ( Vicks Personal Steam Inhaler ) on her, which she hated at first but became able to tolerate whenever the vitamin C kicked in and her breathing passages opened up a bit. Every time the vitamin C wore off, she had a hard time tolerating the vaporizer even for brief periods. One lesson here is that you need to have it ON HAND for use in an emergency. In my case, if I had ordered it even with Prime and waited a day or two for it to arrive, it likely would have been too late. It expires 18 months after being manufactured, so keep that in mind as well. As for its effects on humans, you can search for "vitamin C New Zealand" (or H1N1 or swine flu) on You Tube and watch a "60 Minutes" TV show episode talking about the use of massive doses of vitamin C. These packets can be seen there in the video. Incidentally, a neighbor with chronic HCV (Hepatitis C) knows my dog very well and basically watched this dog with one foot in the grave somehow come back to life. Amazed by this, she immediately purchased a box of this lypo C for herself. She has been combining these with regular vitamin C tablets because the lypoC itself is too expensive to rely on exclusively. 21 packets and 120 vitamin C tablets (60 grams) later (that is her self-reported total after 3 days, taking it to bowel tolerance), she says she suddenly has more energy than she has felt in years and was able to clean her house. Until this time, she was so sick that she was unable to get out of bed and had lost 30 lbs in a year from being unable to eat. She also says she no longer thinks the lypoC tastes funny, because now her body craves it. So that is a human endorsement I can add. [Edit to add: It is now 1 month later and this neighbor says that her hair used to fall out in clumps from her treatment, and that has now stopped.