So, if you subtract 25 mcg
of Cytomel from your regimen, you ought to be adding more like 100 mcg
of Synthroid. It sounds like your doctor might have left you undermedicated in the switch to Synthroid.
I have no personal experience with Cytomel-only therapy, but I do know of people who have been treated with T3-only temporarily. Dosage is very individual, and what others are taking will not apply to you.
Food does not affect Cytomel like it does Synthroid.