Sergeants Gold Flea and Tick treatment made my dog vomit uncontrollably

I found a few fleas on my dog yesterday so I went to the store and shopped for a flea treatment. The only choices at this store was Hartz or Sergents Gold. I chose Sergents Gold and came home and put the flea treatment on my one year old female Lhasa Apso, Zoey. It was around 3pm when I did this. Around 6pm I noticed that she was rolling on the floor whining. I thought that she just needed to go out side so I took her out. She was really figity and would lay down on the concrete. When she would get up I noticed the concrete was soaking wet where here mouth was. I looked at her and her mouth was filled with saliva and foam. I took her inside and she threw up. She tried to eat a little after this but she immediately threw up again. It was such a mess that I grabbed my phone and took her back outside so she could vomit in the grass. I tried to call my vet office but they were closed so I called the emergency vet hospital. They told me that if I could not get her to stop vomitting to bring her in. So I did. The drive took about 25 mins and the entire way there I heard my dog whine and bark like I have never heard before. I could tell that she was in pain and I felt horrible. As soon as we arrived and got out of the car she threw up again. Her vomitting was not normal like how a dog usually heaves and you can see thier body move as they are about to throw up. Her’s was just straight out of the mouth in a split second and thin she would be dripping saliva for the next few mins. I took her into the vet where again she threw up in the waiting room. They did a few tests on her and bathed her twice. The vet came and talked to me. She said that this is not uncommon for people who use Sergent Gold -AND- Hartz. She said that some of the symptoms are vomitting (as in my case), diarrhea, or seizures. They had to give her a fluid injection because she was so dehydrated, and they gave her meds to make the vomitting stop. This product is dangerous! It cost me $185 for the emergency vet vist and even more it put my poor dog in un-necessary pain. My boyfriend and I are trying to everything we can to get this off the market. Or at least warn people about it so they don’t have to go through what I went through with Zoey.