This is a prescription only medicine and so should only be given to the animal it is prescribed for. It may help with fear of fireworks, but it can also have the opposite effect, making them more fearful and thus aggressive. Overdosing can be fatal and giving whilst giving other medication is not recommended, as this can have an additive effect. Please ask you vet for a suitable medication which will only be given after consultation.
I was given phenabarbitol tablets for Bingo to keep him calm and avert his eplieptic fits, I still have half a bottle of his last prescription left, this time of year they were brilliant for keeping him calm through the fireworks and i used to give max one too if it got really bad (he was alot bigger than Bingo). First year I won't need to do that as Max went Nov 16th and Bingo soon after. : (
Why on earth would you risk your dog's life because for about 2 hours in the year he's a bit frightened. If it's so bad, take him out of the area to a quiet place without fireworks.