something to help my dog rest easy

Question
can I give this medicine to my dog a few times a day, or do you recommend just at night?
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-----Question-----
I have a shitzu about 14 years old with cancer.  My vet told me she doesn't have much longer to live and she is home with me for her last days.  She is eating well but she is panting and very tired she hasn't slept for 2 days.  Is there anything I can give to help her rest.
-----Answer-----
Hello John, My heart goes out to you.  The safest thing you could give her would by benadryl for children, Although this is an antihistamine (which is safe for dogs, and given to them when they have allergies)the side effect is drowsiness.  Which for her might not be such a bad side effect.  Usually the dosage is 1 teaspoon per 10 pounds.  Enjoy your time with her and Thanks for asking, Cindy Lou :)

Answer
Hello John, I would give it to her at night and every 12 hours or so if needed.  This medicine will not harm her, it will just take the edge off.  Of course this does not mean every 2 hours.....You know your dog and when you see it wearing off and you feel shes needs it...Then do so.  At this point we just want her to be comfortable.  Thanks again and take care, Cindy Lou :)