Hi linashjoe, corticosteroids like Prednisolone raise bg levels dramatically, I was using Predniolone for over 3 years which was the cause of my T2 diabetes, will you be taking them long term?
If so a low carb diet will help but like the drugs you are currently taking it will only help so much I would advise asking your doctor for a referral to an Endocrinologist or a specialist diabetic unit, they are at most large hospitals, they can then prescribe you start MDI insulin (Multiple Daily Injections) this is where you will inject a long or medium lasting insulin at night which will stop your bg levels soaring through the night and a fast acting insulin to take before meals. Your doctor could do this but he/she will not have the expertise of an endo or specialist diabetic unit.
I found it a great help and saw my bg drop down to non diabetic levels within the first 3 months. I then weaned myself off prednisolone and insulin over the next 12 months.
If you are only going to be using steroids for a short period of time then this approach may not be for you but if you are using them long term as I was it may be the only solution that will get your bg down to safe level.
Good luck.