Badly Damaged

My mother recieved a curl that did not take. Her hair is bone straight and breaking off. The hairdresser believes the curl didn't take due to the medications my mother is taking. What do we do now? My mother has very soft thin hair, that usually will curl when gel is applied and look just like a curl(I still don't know why she put the chemical in it), but now her new growth will not curl and is thinner. Any advise or hair remedies would be appreciated.

She will have to lay off the chemicals and let the damage grow out. She may want to look into more natural hair care treatments and since she is on medication she will need to research to make sure anything she wants to use not cause more adverse effects when combined with other products.