Friend, the fact that both dogs are showing similar symptoms we need to consider that they could have gotten into something, infections, parasites, etc. I would recommend a hands-on examination with your vet and fecal analysis as an initial screening test. In the meantime, this is what you can do:
1- Do not give things like Pepto Bismol or Imodium. You can start Arti on Pepcid AC (famotidine) 10mg every 12 hours for 2-3 days. You can buy Pepcid AC over the counter in any pharmacy.
2- For both dogs no food or water for 6-8 hours, need to give their gastrointestinal tract time to rest. Then, offer a small amount of water followed by a diet of rice (75%) and boiled boneless chicken or ground beef (25%) until the stool is back to normal then wean them back into their regular diet.
3- Supplement with a probiotic, these are friendly bacterias that help with regularity and inflammation. You can buy this over the counter in any pet store.
4- Follow up with your family veterinarian for a hands on examination and fecal analysis.
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