Hi Welcome to HCM
Betaseron is an one of the effective treatment for MS, however decrease in GFR (decline in kidney function) has been reported in conditions such as hypertension
. If you experience dizziness
, flashes of light please consult your primary physician for a consult.
However, looks like your GFR was already lower before you started with the fore-mentioned drugs indicating that the drugs may not be the reason for your lower GFR. I will advice you to consult your doctor if your GFR decreases further.
Hope this helps.