Is it bad to wear contacts for months straight when you're supposed to take them!

Is it bad to wear contacts for months straight when you're supposed to take them out each night?

They are supposed to come out every night and be changed completely every month. But I generally leave them in for a few months straight and then throw them out. is this really bad for my eyes?

Yes this is extremely bad for your eyes for sooo many reasons. I know it doesn't seem important to you to follow the directions of the contacts...but improper contact lens wear can cause permanent damage to the point where you may never be able to wear contacts. Certain contact lens materials are not made to stay in your eyes overnight. Your contacts can dry out and get stuck to your cornea...this can result in damage to your cornea.
Naturally your eyes produce protein and this builds up on the lenses, even with cleaning them thoroughly the deposits remain. These deposits irritate your eyes and also "clog" up your contact lenses and the amount of oxygen getting to your cornea is reduced.
If you over-wear your contacts your cornea will not be able to tolerate it. Wearing lenses for extended periods of time can block oxygen to the cornea, making it more susceptible to infections.
Also improper contact lens wear can result in a corneal ulcer. This happens when the surface of the cornea is damaged or compromised. Want to see what a corneal ulcer can look like? http://www.littlerockeye.com/photogaller...
This is more serious because bacteria may be on the lens or in your cleaning solutions, thus, they get trapped on the under surface of the lens. If your lenses are left in your eyes for long periods of time, these bacteria can multiply and cause damage to the cornea. This can even result in blindness or the inability to wear contacts.
Please give your eyes a break they need it!!!
Please see an eye care professional to check your eyes and talk to them about proper contact lens wear and the consequences of not wearing them properly. :)