does cannabis and or thc interfere with ritalin effect?

hi all

i haven't found anything very conclusive or informative, but there's some mention of ritalin and cannabis attaching to the same cb1 receptors??? if so, can pot out compete ritalin, rendering ritalin ineffective?

I don't smoke pot a lot, but i do take thc or pot almost every single night... usually just enough to sleep - sometimes more, lol. never in the day. if i smoke too much at night, say, half or a whole joint, i feel it the next day. a pot hangover.

i'm also definitely interested in people who notice no effect and are happily indulging in both ritalin and pot.....

20 years ago, i tried ritalin, and could barely tolerate 5 or 10 mg. i'd get jittery, and noticed it could really focus me. now, since i take thc or pot, i'm up to 20mg... i don't notice many or any side effects --- it seems to help my focus. we've been upping my dose.............5 ...10......15 over three months... now i just started 20.  

thanks so much. stay healthy.