It seems that some individuals develop a tolerance of sorts to ADHD medications, although there’s no research to back that up that I’ve been able to find. My son’s Concerta would lose effectiveness every 2 months, like clockwork. We kept increasing the dose, and it kept happening. We ended up with a moderate dose of Concerta and added Amantadine, and that worked for him for about 2 years (ended up with extreme fear episodes from the combo so we had to stop the Amantadine). Once he hit puberty, losing effectiveness with Concerta alone wasn’t a problem anymore. That makes me wonder if there’s something different going on in your body.
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ADDitude Community Moderator, Author & Mentor on Parenting ADHD, Mom to teen w/ ADHD, LDs, and autism