You should not be giving your dog Benadryl. You need to ask yourself: why is my dog so hyper? Chances are, you are cranking the dog up by teasing it, ignoring it, neglecting it, or abusing it, pushing it away, forgetting to give it water, and a host of other things. My dog is terified of thunderstoms. Pants, tongue hanging out, eyes huge, and heart beating really fast. Can I give her Benadryl to calm her down and how much? Hello. Yes, Benadryl is ok to give dogs as a mild sedative for storm phobia. The dose that you can use is 1-2 mg per lb every 6-8 hours as needed. Maybe. It's fairly safe As a drug. Pregnant women can take it. My dog got stung by a bee and her joules started swelling. The vet told us to give her one And it worked well. Giving Benadryl to your dog: should you do it? Is it helpful and harmless? Or is Benadryl for dogs dangerous and a bad idea? Used properly, in the right situations, Benadryl can be a lifesaver—preventing headaches and alleviating discomfort for your dog. If he's aggressive, you won't be able to give him enough to calm him down without overdosing him. Giving OTC meds to a dog is a BAD idea without your vets say so. How much Benadryl should I give? The standard dosage for oral Benadryl is 1 mg per pound of body weight, given 2-3 times a day. Most drug store diphenhydramine tablets are 25 mg, which is the size used for a 25 pound dog. Sometimes you can give him treats or pet him continuously but there's really not a lot of things you can do to calm a dog down for grooming. The best thing you can do is to keep taking him over. My dog is normally ok with fireworks but tonight she is very scared with the neighbours display and is hiding in the toilet, we have valium in the house can i give her this as she is getting herself w ….