It really depends on your complete situation. I have had Crohns for many years and was able to work full time. about
a year ago I got much sicker and had my 3rd resection, which resulted in short gut syndrome. So now I'm on daily TPN to make up for all the nutrients I lose through my ileostomy. I am generally fatiqued because of the Crohns and nutirition issues.
I applied for SS Disability in January and was approved in April. I'm told I'm one of the lucky ones; nearly 60% are turned down the first time and must fight it.
There's a lot of paperwork involved. Having the support of your doctors is very helpful, for it is also their recommendations that carry weight on the decision. My GI was very helpful in the process because he felt I was unable to work anymore. When you originally submit your application, send as much of your hospital records as you can - anything that will support what you have been going through.
If you don't get approved the first time -- don't give up!. File your appeal right away. And if you really feel your case is solid, hire an attorney and get in front of a judge.