I have not heard back from you and since this is a time sensitive situation, I do want to leave my thoughts in case you are having any issues replying here.
Now the good news is that all three of these components are used in dogs and therefore this isn’t an outright poisoning. That said, while the Melatonin and the hydroxytrptophan doses are a not worry, he has had quite a high dose of Suntheanine. That said, it tends to be well tolerated but we could see GI upset, cramps, diarrhea, and lethargy/headache from such a dose. Of course, in this combination, we could see him be quite sedate and lethargic anyway.
Now one we caveat to that that I do want to mention is some of these preparations are made using the artificial sugar xylitol. This is dangerous to dogs as it can cause blood sugar crashes and harm the liver. Therefore, do check the label for this. If it is present, then we will want to be proactive here and get those tablets out of his system quickly.
Otherwise, if there isn’t any xylitol, we do have a few options on how to approach this. We can choose to err on the side of caution by inducing vomiting if it has <2 hours or using activated charcoal which is of benefit up to 8 hours post ingestion. Otherwise, we could choose to monitor and offset any GI upset this could cause.
In regards ***** ***** vomiting, you can do this at home by administering 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 – we just want to get it in. After giving this orally, move the abdomen around or get your wee one walking 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 your local vet (or ER vet) so that apomorhpine (a very strong injectable emetic) can be administered just get this out of the stomach and avoid any adverse issues.
As well or alternatively, you can also use activated charcoal at this stage. This is available over the counter from the pharmacy (ask for the high strength version in grams, not the one for gas since you will need a lot of these) 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 is absorbed and reduce the intoxication risk here.
Finally, after the above or if you choose to monitor, we do want to try to address any potential GI upset here for the next 24-48 hours. To do so, you can consider offering a light diet option for a few days. Examples of an easily digestible diet include cooked white rice with boiled chicken, boiled white fish, scrambled egg, or meat baby food (as long as its free from garlic or onion powder). Ideally, we want to offer this as small frequent meals to keep the stomach settled. Further to this, if we see any hints of nausea, then we can also treat with an OTC antacid like Pepcid (More Info/Dose @ http://www.petplace.com/article/drug-library/library/over-the-counter/famotidine-pepcid) or Zantac (More Info/Dose @ http://www.petplace.com/article/drug-library/library/over-the-counter/ranitidine-hcl-zantac). These are usually given 20 minutes before offering food to allow absorption and of course you want to double check with your vet before use if your wee one has any know health issues or is on any medications you haven't mentioned.
Overall, these are all supplements we use in dogs from time to time; therefore we don’t have an outright poisoning. Still, considering the average weight for his breed the suntheanine is a bit high. Therefore, we can use the above options to address this for him and ensure he has no harm from this situation.
Please take care,
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