RISDONE is associated with tremendous weight gain.
Even DEPAKINE also results in weight gain but not that much as RISDONE.
Since you have already stopped RISDONE,it would be easier for you to reduce weight by adopting lifestyle changes like eating healthy ( more of veggies and fresh fruits and avoiding fatty,fried and junk foods ) .
Along with healthy diet,you must start doing regular aerobic exercises
for minimum 45 minutes a day.
Although this would take some time but do stick to it,as there is no short cut healthy method of shedding flab.
At the last,since you have totally stopped taking RISDONE,you may get withdrawl symptoms like dizziness
etc.In such a case you should consult your doctor as early as possible.