It seems each rheumy has a different way of doing things. I was told to take folic acid each day, and initially it wasn't enough and the MTX really had me down, to the point that it would be 10am, and I would be struggling to get out of bed,(horrid fatigue) so at that point, my rheumy prescribed a medication called Leucovorin (sp?) to help with the side effects of the MTX.
Hopefully someone else will come along who has taken it 48 hours after their dosage. I understand your concern!