Hello, I am afraid that the expert you have requested is not currently available. Still I am Dr. B, a licensed veterinarian and I would like to help you with your wee one today.
Now if you suspect she has had this at all, it would be ideal to induce vomiting now or get her local vet involved. The reason is because this is a very high dose for her weight. At this level, it would act as a sedative and cause depression of her nervous system. As well, it can make them restless, anxious, lethargic, depressed, increase appetites and thirst.
To induce vomiting at home, you can administer 3% hydrogen peroxide orally at a dose of 1ml per pound. (2 teaspoons per 10 pounds of body weight). You can give it via dropper, syringe, turkey baster -- just we want to give it orally and get it into her. After giving this orally, move the abdomen around or get her to walk about to get things mixing. This should usually lead to vomiting. If it is unsuccessful after 10 minutes then it can be repeated twice more. And if we still have no vomiting, then you'd need to consider seeing the ER vet so that the vet can administer apomorhpine (a very strong injectable emetic) to just get this out of her stomach
and avoid any adverse issues.
As well, you can also consider administering activated charcoal at this stage. This is available over the counter from the pharmacy (ask for the high strength version, not the one for gas) and works by binding any remaining material in the stomach. For activated charcoal, we tend to give 1-4 grams per pound every 8 hrs. This can be mixed with food to be fed or with water to syringe feed (do note that it stains, so keep it away from white carpets/clothes). This will just limit how much she absorbs and reduce the intoxication risk here.
Finally, if you do not have the above on hand and cannot get this tablet back, then do consider seeing her vet (or an ER vet) urgently. They can take the above steps to limit the dose she has but also start her on IV fluids to flush the drug out of her system faster and avoid those serious adverse effects of this high dose.
Just in case you need a local emergency vet, you can check @ http://www.vetlocator.com/ -or-
Please take care,