This is a relatively new drug for treatment for Type 2 Diabetes, Type 1 of course uses Insulin Injections.
Type 2 Diabetes is normally controlled by either diet alone (watching Carbohydrates etc) or diet and tablets such as Metformin which together with blood tests can keep the condition under control.
If indeed this is what you have been prescribed the drug for Paul?
Do not know of anyone currently on this drug but manufacturers web site may help?http://www.byetta.com/Pages/byetta.aspx
I would discuss this with the Diabetic specialist at your hospital/clinic to find why they also think this is the best course of treatment.
DVLA and Insurance would require notification and you switch to a three yearly renewalable licence after a medical checkup and report.