Can you ask your employer to do a different or another job if your doctor says you are unable to do your current job?

Yes, you can always ask, but keep in mind that in most circumstances your employer is under no obligation to either provide you with work within your restrictions (however, if they don't have work for you then you should receive a weekly workers compensation check) or provide you with work that you feel is more suitable.  In most situations, you are an employee at will and if you reject work that is offered to you within your restrictions then you may be fired and also receive no weekly workers compensation benefits. 
Corey Walker
With 19 years legal experience, Corey has been recognized for his work as an injury attorney.