Advantage Flea Treatment Side Effects. Potential side effects of advantage multi for dogs: Depression, salivation, dilated pupils, incoordination, panting, and generalized muscle tremors.

What are the side effects of advantage multi for dogs? As for whether or not your pet should receive flea treatments during the winter, some veterinarians suggest a “better safe than sorry” approach. Advantage ii is probably one of the 'safer' flea meds, in terms of possible side effects.