I believe I can help you with your concern today
Is 300 mg of Effexor XR too much to take
The 300mg of Effexor ER is extremely high and actually not recommended by the manufactures. There was a study for severely depressed individuals that responded to Effexor (the immediate dosage not the Extended Release that you are taking) at 350mg that was very effective. But to date there have been no effective studies on over 225mg for Effexor ER
So I would not recommend it at this time, unless you are monitored by your doctor because the increased amount of Serotonin in you can cause serious side effects unless you are carefully monitored
Should I slowly scale back
Now the manufacturers are usually very cautious with their dosages, so the 225mg may be a conservative estimate by them and 300mg may not be dangerous, but there are no studies right now to prove that. Yes you should scale it back gradually. I would take 300mg every other day for a week, switching from 300mg to 225mg then go back to 225mg every day after the week
You are most welcome, is there anything else I can assist you with today?