What happens to chemically straightened hair after 6 months?

[Ruby]

I thinking of getting my hair chemically straightened. I am well aware of the downsides of this treatment but I was wondering, do the tips of your hair gradually start going back curly and normal after the 6 months?

[Sur La Mer]

I do no recommend them, that's $300 - $800 each time you get them done. One I responded, she had hers done in March and that was May when she posted it? It is a trillion dollar business, and they do not give money back guarantee for damaged hair or hair loss due to 'abuse', in this case, cancer.
Hair straighteners are known as hair relaxers, keratin treatments and hair-smoothing products. They work by breaking and reforming the chemical bonds in keratin, which is the main protein that gives shape to each hair.

The FDA has previously received complaints that the products cause adverse reactions, including nervous system problems such as headaches, respiratory tract problems, nausea, chest pain, vomiting and rashes.
12-12-12
Hair-straightening products are allowed to contain small concentrations of formaldehyde (0.2 percent). But several hair-straightening solutions have been found to contain well above the allowable limit. For example, one popular hair-straightening product that advertised itself as “formaldehyde-free” actually contained 6.8 percent to 11.8 percent formaldehyde.
Another example: Fourteen women, including two from North Texas and one from Houston, are suing Unilever, the maker of a product they claim caused permanent damage to their hair.
"It transforms frizzy, unmanageable hair into hair that's sleeker and easier to style," said the commercial for the Suave Professionals Keratin Infusion 30-Day Smoothing Kit, which is no longer being sold
When she began looking online for more information about the product, she said she found some people who said it worked, but more who said it damaged their hair.
She discovered a Facebook page devoted to angry consumers, and there are multiple postings on YouTube. I've been warning people about relaxers since 2009 and people are giving me thumbs down!
BTW: A variety of hair-straightening products used in professional salons can expose both hairdressers and their customers to formaldehyde. The results show that three professional hair-smoothing treatments labeled "formaldehyde free" can produce the cancer-causing chemical at concentrations above the occupational exposure limits set by the Occupational Safety and Health Administration. They tested four products: Coppola Keratin Complex Blonde Formula, Global Keratin Juvexin Optimized Functional Keratin, La Brasiliana Escluso Keratin Treatment with Collagen, and Brazilian Blowout Acai Professional Smoothing Solution. While ChemRisk tested four popular brands of hair straighteners, THERE ARE HUNDREDS on the market. Nov. 11-11

By contrast, beauty salon owners and stylists generally lack a scientific background and don't have a keen awareness of the danger of working with products that contain formaldehyde, experts say.

Watch: Good Hair a documentary by Chris Rock 2009 on BET or HBO. According to Tyra Banks, 80% of the black population are part of the billion dollar hair industry. Clips on youtube videos, also.

Chemicals can enter the body through the skin.

Sources:
Google FDA.gov & search for Hair Dye & Relaxers.
Google: Hair Dye FAQ's Are Hair Dyes Safe?