This is from another board I'm on (in response to a dog who is heartworm positive and so advanced that it is danger of dying from the treatment) and I requested permission to re-post and it was granted:
This will kill heart worms without endangering the dogs as what the beer does is is make the worms sterile. It's seen as food by the worms so they don't put out the poison to try and stop the dog from eating anything more that 'bothers the worms', plus the die off of the worms is slow so there's not toxic overload there. This was studied in Japan.
The tests were done with several types of beers and the Guinness Draught is the one that works. This is because 1) the special ancient type of hops they have there and 2) the really good water. It's the hops that sterilize the worms. This special hops is only in the Draught Black Label beer imported directly from Ireland. I originally purchased Guinness Stout but when I got home I read where it comes from Canada and they don't have the special breed of hops. Only the Ireland Import does.
The dosage is 1 ounce of beer to 25 pounds of weight. Normally people let the bottle sit with the lid off to get rid of the carbonation (so the dog doesn't get gas). It's ok to let it go completely flat, and if you don't use up the whole bottle in one setting you just cap it and put it in the fridge. The hops never 'go bad' and so it will work until you empty the bottle.
So you give 1 ounce of Guinness Draught to 25 pounds of weight every 2 weeks. Just pour it over their food if they won't lap it up (some will, some won't) After 3 months you can have the dog tested to see if there are any filarie left (baby worms). If so, continue for another 3 months and test again. When all the baby worms are dead then you switch over to dosing once a month.
This kills all worms except whip worms.
I hope her dog can last long enough to utilize this treatment. Very simple, very cheap and it works. There are a couple ladies on a pet list I'm on who foster dogs. They have had dogs tested to have heart worms, put them on this beer method, and then the dogs are tested and--no heart worms. All the foster parents in their groups use this now.
Further posts discussed how hops is toxic to dogs, but it turns out that it's misinformation - the hops dregs from making the beer is toxic to dogs, but not the portion of hops that remains in the beer. They researched this heavily because they are in Florida and in rescue and many dogs were coming through as heartworm positive. The amount of alcohol needed to kill the worms is not harmful to the liver, and the treatment has been extraordinarily successful in their rescue program.