How often can you dye your hair?

Does anyone know how often you can dye your hair? (dye not bleach). Because even permanents wash out within 4 weeks on me.

I do my hair anywhere from 3weeks to 6 weeks I do home coloring never done the regrowth only bit LOL my hairdresser is so surprised how good a condition my hair is in so I know its no harm and I have been dying my hair since I was 15 so nearly *eek* 19 years (due to early grey)

I do mine every four weeks or so... the grey hair grows too quickly to leave it any longer!

what sort of shampoo do you use?
Might be worth getting a salon shampoo for coloured hair - if this keeps your colour longer it may work out more economical that colouring it as frequently.

I only ever dye my hair maybe once every three or four, sometimes six months. Just because it grows really, really slowly and it's so long that nobody notices an inch or two of regrowth.
As long as you're not pregnant I don't see any reason why you can't dye your hair every 4 weeks or so, try investing in a really good quality set of products to help prolong the life of your colour. Also, cut down on blowdrying/straightening and product use as much as you possibly can, and wash your hair as infrequently as you can. I can get away with washing my hair once or twice a week because I hardly ever (ie, maybe once every two or three months) use product in my hair (and even then, it's just an oil-based shine spray, not harispray or gel that stick and can strip colour), and I never blowdry or straighten my hair.
Also, the best tip I ever got while I was hairdressing is to avoid Pantene products like they're hair-removal creams - they are notorious for stripping colour and they're really no better for your hair than the $3 supermarket brands. Try Redken, I've always had good experiences with their shampoos and conditioners.

Do you dye your hair yourself, or at the hairdressers?
I used to have the problem of my hair not holding dyes for very long (even permanents) and I was using the shop bought dyes.
I switched to the dyes you mix up yourself with developer (the same type hairdressers use), from a hair wholesale shop, they have been fantastic.
I'm lucky enough to have a hairdresser friend who taught me though.
Apparently every time you dye your hair with a permanent you are stripping the colour from inside the shaft and putting a new colour in. Whereas a semi just coats the outside of the hair shaft.
So dying your hair permanent, (if its using the same colour!) every 4 weeks, may not be as effective as you think, as you are restripping your hair each time.

with the shampoo if your using one with silicone in it them the dye wont stick to the hair well!!