Brief Answer:
Adderall XR causes delayed absorption of Modafinil by an hour.

Detailed Answer:
Hi XXXX,
Thanks for writing in to us.

I have read through your query in detail.
To the best of my knowledge and after having reviewed latest medical literature Modafinil (a medication to promote wakefullness) and Adderall XR (amphetamine/ dextroamphetamine) interact with each other at a minor level when taken in prescribed doses.

Adderall XR (amphetamine/ dextroamphetamine) causes delayed absorption of Modafinil by at least an hour and this can prevent the medication from acting as it is expected under normal circumstances. This is not a serious concern and can be discussed with your doctor keeping in mind the benefits and risks associated with taking both the medications together.

Hope this answers your question. Please feel free to correct any oversight in my interpretation of your problems and discuss them in detail as per your requirements.

Hope your query is answered.
Do write back if you have any doubts.

Regards,
Dr.Vivek

---