After adding indexes to an AWS RDS MySQL DB getting huge/crippling spikes in IOPS
Few things you can look forward to this issue.


IOPS limit is based on your volume size if you are using General Purpose SSD.
And IOPS are your reserved IOPS. 


In staging its fine. Check both volumes are in the same size. 
Sometimes you are getting a sudden spike, in this case, enable Enhanced monitoring to track every 1sec of MySQL activities. 
Enable slow query log and set the long-running query time to 0. So it'll capture all the queries. 
Compare the enhanced monitoring IOPS graph with the slow query log table, then you can get an idea for the bad queries.