One of our elderly dogs is very frightened of fireworks. There is an excellent and very useful factsheet from the BSAVA here which discusses the main treatments, both short and long term and the issues to consider.
On Guy Fawkes night, NYE and a couple of other evenings we use a Diazepam med for our girl and it has helped considerably. Snoopy's point about the meds applies to ACP, as discussed on the factsheet above, and our vet (and most others, I think) would no longer prescribe it for that reason.
You can also consider actually physically getting away. If you live in a very urban environment, it may be helpful on Bonfire NIght, NYE etc to try to spend some time in a place that is quieter and more rural. We've done this, especially in the run up to Bonfire NIght and it has been very successful.
Locally, the police have got much better about cracking down on firework usage before the main Guy Fawkes night and we've had some success in making sure that every occurrence is reported via 101 (non emergency number). Last year, I was actually delighted with how little random noise there was outside the expected main nights.
Finally, I think the factsheet actually makes the v important point that some modern fireworks are so loud that a fear reaction shoudn't be regarded as a phobic response, but as a completely understandable reaction to what is a very very loud bang.
One other point to mention - if you have more than one dog, it can be helpful if the fearful dog can see another dog being calm and chilled out. We have three dogs - one is v fearful, one is completely chilled out, and the third gets a bit cross when there are lots of loud bangs but isn't actually fearful. We make sure fearful dog can see all of us (including other dogs), can hide away if she wishes, or can have a gentle cuddle if required.