Not typically, but you will likely have to do a Drug and Alcohol Evaluation and that evaluation will determine what type of classes and/or counseling you may be required to get. You may have to complete DUI Risk Education, Drug and Alcohol Counseling and/or Aftercare Treatment. This is a great question for your attorney. If you have not hired an attorney yet, you should do so right away. DUI charge is not something you want to handle on your own or wait to hire the right attorney.
If by "rehab" you mean inpatient treatment, not necessarily. But if you are convicted or receive court supervision, most judges will require you to obtain a drug and alcohol evaluation and complete the recommended hours. How many hours will depend upon your risk level.
