If you have used a product like tick and flea spray, or shampoo, the symptoms of overdose are varied and can range from mild to severe. All flea and tick medications are toxins, and the serious side effects are; staggering, panting, convulsions, pupil dilation (large pupils) and stiffness in limbs. If you feel your animal may be suffering from an overdose, I highly suggest you seek medical attention promptly. Some symptoms are mild and last only a few hours, while others can be permanent. If you have applied something topically, rinse the animal thoroughly in warm water. Please call the vet if symptoms worsen or animal shows any signs of shock. For more information on how to safely rid your pet of parasites, go to liveperson and ask for me! I sure hope your animal is ok!