I'm so sorry to hear of your friend's Miniature Daschund. I did a little bit of searching, was he exposed to seomthing in the grass outside possibly?...
Flea Treatment Poisoning
Most pesticide chemicals in commercial flea repellents are fat-soluble and are stored in the fatty tissues of the body, primarily in the liver and in the nervous system. As these chemicals accumulate over time, they negatively affect nerves, hormones, and immunity. Symptoms to lookout for include anorexia, cancer, colic, convulsions, deformity of sexual organs, depression, diarrhea, foaming at the mouth, nausea, seizures, stiffness, vomiting and weakness, according to Anderson and Peiper.
Pyrethrum, a nontoxic insecticide made from chrysanthemum flowers, is found in may flea repellant products and is considered safe in its natural state. However, combine pyrethrum with chemical additives and you have a potentially dangerous environment for your dog. Chemical additives to look out for include diethyl toluamide (DEET), propoxur, diazinon, carbaryl, dichlorvos, and DDVP. Be forewarned: constant inhalation of DDVP, found in flea collars, can causepermanent damage to your dog's internal organs.
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