G'day Ale!
Just some ideas for you.
ADHD is usually treated with medications to increase dopamine in a specific area of the brain at the front where our decisions are made and impulsivity tends to come from. Trouble is these medications also tend to have an affect on a group of molecules called catacholemines, which include adrenaline, a molecule responsible for the "fight or flight" response. Putting it extremely simply, when we are in a "fight or flight" mode we are no longer in the opposite mode of "rest and digest", so essentially appetite is suppressed by these types of drugs. It's difficult to have an appetite with butterflies in the tummy.
Having said that, kids with ADHD are more likely to be found somewhere on the autism spectrum. In this case picky eating can be a result of sensory issues to food like colour, texture, taste, size etc.
Talk to the practitioner who diagnosed/prescribed your child first and foremost. Also strict parameters surrounding meals need to be adhered to. Which means meals at the same time every day, a certain percentage of a meal must be consumed every sitting, and a certain amount of time per sitting must be enforced also. So not eating meals for ten minutes then TV for twenty minutes, then the meal for another five minutes, and setting a reasonable amount of time in which a meal should be consumed. It's ok to be the last one to complete a meal out of the family but an hour after the last family member might be an issue.
Talk to the practitioner who diagnosed/prescribed your child first and foremost.
God bless!
