mixing alcohol and concerta is just in general a bad idea, as far as i'm concerned alcohol is the antithesis of adhd-medication,

we take medication to be more in control of our lives, focus is part of it, getting stuff done is part of it, but it helps put us in the drivers seat in a sense,

alcohol does the exact opposite, primarily this should be obvious

the stimulant will also amp you up while the alcohol will reduce your inhibitions, meaning you'll feel more sober than you actually are, probably have a lot more energy, that can lead to some manic behavior;

there's another issue of methylphenidate and alcohol interacting and as a result it turns into a completely different substance, but this is pretty minimal afaik;

point being though, if you're planning to drink, take your meds earlier in the day and make sure they've properly worn off before you do, otherwise, don't drink.

I always found drinking on concerta led to me really drinking way more than I thought I was and, to be honest, I hadn't ever experienced black outs from alcohol until I started mixing the two,