Does anyone know about hair drug testing? How far back it tests for and so on.?

up to 90 days

Does anyone know about hair drug testing? How far back it tests for and so on.?

That depends on the length of the hair. Back in olden days Kings were killed by poison-arsenic, now years later the hair still showed the arsenic and how long it had been given. So, hair is better at determining the length someone has used instead of its current existence as in urine and blood.

Does anyone know about hair drug testing? How far back it tests for and so on.?

I'm thinking it goes back as far as 3 months, and can test for any type of narcotic....

Does anyone know about hair drug testing? How far back it tests for and so on.?

Haha, you're in trouble if you're asking! It can go as far back for as long as your hair is. Generally, most jobs only look back as far as 3 months (just an inch or so of hair). Don't bother shaving your head though, because they'll look at your arm hair or leg hair. If you show up with no hair, you'll be fired or let go!

Does anyone know about hair drug testing? How far back it tests for and so on.?

It goes back six months.