My 3 year old boxer was throwing up last night and today she is weak and won't eat or drink I can't afford a vet is there anything I can do at home to make her better

Take the dog to a vet and work out a payment plan. We can't diagnose or offer suggestions since we have no idea as to what may be wrong. Why have a dog if you can't afford to help them?

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Sadly there's nothing we can do. Any suggestion we make would be a guess, and it would also cost money because any suggestion we make would involved getting a few supplies, none of them cheap. The vet would actually be cheaper, especially because we're only guessing, and our guesses likely won't work to cure your dog.

I understand not having money, but call your vet, ask if they'll do a payment plan because this is an emergency, and trust me, this is an emergency. You don't have time to wait. Not eating, not drinking, vomiting, she'll likely be dead in a day or two unless you get this treated.

For now give her pedialyte or gatorade. Throwing up and not drinking will make her dehydrated. Pedialyte pr gatorade will help with that and may keep her alive long enough for you to get her to a vet.

Good luck.