My parents elderly bitch has a bad case of flea dermatitis. They have tried flea collars, powder, shampoo & Frontline all to no avail!
She has lost a fair bit of hair and their vet can offer no other advice.
Has anyone got a tried & tested method whether it's holistic or otherwise? 
Can somebody help out this poor dog before she is completely bald! My parents & Rosie are desperate.
Thank you.

Have they treated the house/environment with a product that has an insect growth regulator (Acclaim etc) that breaks the life-cycle.  Depending on product they are effective fro 6 - 12 months.

Not only is that the most efficient method of dealing with fleas where 90% of the problem is not on the animal, they are just a convenient moving feeding station, not where fleas live.

My very first bitch had this, and I used Frontline as a preventative even though we never found a flea on her.

treat the house. fleas spend 90% of time off the dog. without treating the house properly they are hard to get rid of.  if your parents infirm then maybe consider a pest control firm to spray house with something real effective .
at same time treat the dog with spot on treatment.and treat any cats that live there.

ban all visiting dogs/cats unless you are certain flea free else you will just get them reintroduced.

Thank you folks. I've not heard of Acclaim before. Is it available in the high street pet shops or just on-line?
Also would a carpet steamer help kill these critters in the soft furnishings?

i have heard boric acid is good. It is a very strong substance for  range of different jobs for it, getting rid of fleas one of um, orthough not very publicied. Take a look on the net for advice on it, if i remember correctlym it is not dangerous. I had a terrible fle problem last year at this time from my 2 cats and it was the home that was the problem and i was treating my home every day to try and get rid of them and nothing worked for months, they just kept appering, and was treating the cats by hand every night, nothing was getting rid of them and i was that fed up with it i nearly just moved out, i saw boric acid and was about to order of ebay (very cheap it was aswell) as a last resort but then fleas just dissapeared completely (or so it seemed) so maybe try boric acid or just keep treating house every day and checking animals and treating them by hand (removing fleas and craking them between your nails, or grab them and drown them n a bowle of water by holding them down untill no movement as they can climb out of water you have to DROWN them) and hopefully like mine the problem will eventually be killed off :) Good luck, i no how horrible it is for humans and the animals xx

Vets will have various ones, and on-line pharmacies.  Have also see it in chemists.

Here are several different ones: http://www.vetuk.co.uk/flea-treatments-household-flea-sprays-c-3_419

You can buy Acclaim in most branches of Boots for around £13 = enough to treat an average 4 bed house.

Is it definately flea dermatitis or is there any chance it may be a food/environmental allergy?

> Is it definately flea dermatitis or is there any chance it may be a food/environmental allergy?

They also kill house dust mites so might help as that is a common allergy cause.