I like the sound of a 50/30 split. I'm partial to 2/3 of the dose in the morning and 1/3 of the dose in the evening. That would be closer to a 55/25 split but it doesn't need to be precise.

I'm impressed with what that Chief of Rheumatology said ... "find what works so long as it's 80 mg per 24 hour period."

When you taper to 60 mg daily, the split dose can be 40/20. If all goes well you can taper in 3 mg increments with the morning dose decreased by 2 mg and the evening dose decreased by 1 mg. The 2 to 1 ratio is maintained that way. 38/19 ... 36/18 ...34/17 ... 32/16 ... 30/15 and so on. Fun with numbers!

It helps to have a good supply of 1 mg tablets! Actually 20 mg, 10 mg and 5 mg tablets are all good to have. My doctors would order all the different strengths of tablets and the number of tablets to be dispensed. My instructions were "take as directed" without spelling it out. The pharmacist dispensing the prednisone will appreciate it being ordered that way. This depends on your doctor trusting you to take prednisone as directed and not going rogue!

When you get below 10 mg, I would consider going back to taking the entire dose in the morning. The issue is about adrenal suppression when a person is on long term prednisone. Supposedly taking the entire dose in morning reduces that risk of adrenal insufficiency. At higher doses above 10 mg daily, the adrenals will be suppressed whether you take the entire dose in the morning or split the dose.

I have never tapered for GCA. However, I have followed these guidelines many, many times for uveitis which can also cause vision loss. How fast one tapers depends on what is being treated. There is no single best way to taper prednisone!

When I was on Prednisone for my GCA, I split my daily dosage anyway I wanted with no ill effects because I thought I was supposed to. Three 10mg tablets a day I assumed meant one every 8 hours, so that is what I did. I didn't realize that I COULD take it all at one time. After being off Prednisone for 6 months and being put back on it for 6 months prior to switching to Actemra, I just took the entre daily amount at one time. Felt no difference between the two ways.
Actemra worked fine for me for the 90 injectins I took (on each week). No side effects, and it cleared up my GCA to the point I was able to stop taking it after 90 weeks. There has been a slight expected "back slide" after stopping. I now have periods of tiredness during the day similar to the feeling I had prior to taking it. But, my doctors haven't pinpointed the reason. Many things can cause this including poor sleep habits, depression, medical, or other medications. I think I should have continued the Actemra, but at a lower dose. My clotting platelets were creeping lower with the Actemra and I have a touch of thrombocytopenia so that was an added incentive to cease the Actemra. Once off the Actemra, my platelets went back up.

The day after the last two injections of Actemra i have experienced blood pressure readings quite a bit lower than normal and unusual fatigue. Back to normal the following day.

Split dosage:
I would follow the recommendation of the Chief of Rheumatology.