Hmm
The maximun recommended dose on Ibruprofen seesmms to be 3200mg per day
A few sites but here's the Mayo clinic on it
http://www.mayoclinic...5/DSECTION=proper-use
Certainly higher doses like 3 or 4 tablets seem common provided you stay in that.
600mg every 4 hours gives you 3600 mg in 24 hours
If you're worried you could alternate between 3 and 2 tablets but you'll probably miss a one anyway overnight.
Obviously stop if that "whoosyness" gets worse - some people have reactios to Ibuprofen - my daughter certainly does