Welcome to Just answer !
Well, you have rightly pointed about the durations of concerta and ritalin ir , as concerta and ritalin both are methylphenidate psychostimlant drugs , the difference between is that concerta is a long acting version while riatlin ir is a short acting one.
The reason that these drugs which have been doing fairly well since many years for controlling your ADD
symptoms , have started to lose their previous effect , is that , your body has developed resistance ( incraesed tolerance ) against these drugs , which is very often seen in cases of almost all the drugs , and when such a thing happens , we have three solutions--
1) To up the doses of the drugs .
2) To change the formulations , as you are suggesting that to switch over to Ritalin SR , which is sustained release , and thus longer actng than ritalin IR .
3) Switching over to another drug , for example you may change to another equally potent psychostimulant , which like ritalin ,is also worldwide used for treating ADD/ ADHD , and that drug is Adderall XR.
So, i suggest that you first discuss with your doctor to up the dose of concerta and switch over to ritalin SR , and continue on this for 1 month , and see the results , if you still find lack of control over your add symptoms by these drugs , then i will suggest that you ask your doctor to switch over to Adderall XR ( long acting version , covers the entire day).
I am mentioning below a link which will throw more light on the use of ADDERALL XR in ADD.http://www.rxlist.com/adderall-xr-capsules-drug.htm
I hope this helps..
I wish you all the best of health.
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