Heidi might be allergic to penicillin. It might be an idea to contact the breeder and find out about the medical history of Heidi's for-bearers. For a long time after I got Mister Two Dicks, he would throw up for what I though was no reason. I would give him dry food, he would throw up. I would give him canned food, he would throw up. I would give him beef bones, he would throw up. After much complaining to his breeder and others, it suddenly dawned on his breeder that Mister Two Dicks' grandfather was allergic to beef. Ever since, no beef, no throw ups. It could be that Heidi is allergic to something and it is hereditary. Just a thought.
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