Attention Deficit Hyperactivity Disorder Treatment for Children, Teens, and Adults

ADHD Evaluation and Treatment in Manchester, NH

Q: My daughter isn't hyperactive, but she struggles to focus and finish her work. Could it still be ADHD?

Yes. Inattentive-type ADHD often looks like daydreaming, disorganization, or difficulty finishing tasks rather than visible hyperactivity, and it is significantly more common in girls than the hyperactive presentation most people picture. This presentation is frequently missed or mistaken for anxiety or a learning issue.

Q: Does Attention Deficit Hyperactivity Disorder medication stunt a child's growth?

Stimulant medications can cause a temporary decrease in appetite, which is why we monitor growth and weight closely during treatment. For most patients, any effect on growth is modest, and we adjust the treatment plan if we see a concerning pattern. This is a conversation we have directly with families, not something we gloss over.

Q: Can adults be diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) for the first time later in life?

Yes, and it happens often, sometimes prompted by a child's diagnosis, sometimes after years of attributing symptoms to stress, personality, or another condition. Adult ADHD evaluations follow the same rigorous process, adapted for adult symptoms and history.

Q: What is the difference between ADHD and just being disorganized?

The difference is impact and consistency. Everyone loses their keys occasionally. ADHD involves a persistent pattern, present since childhood in most cases, that meaningfully interferes with school, work, or relationships across multiple settings, not just one bad week or a stressful season.

“He’s just a boy being a boy.”

“She’s not hyperactive, so it can’t be ADHD.”

“I’ve always been disorganized, that’s just my personality.”

I hear some version of these almost every week, and they are exactly why Attention Deficit Hyperactivity Disorder (ADHD) is one of the most under-diagnosed, and sometimes over-diagnosed, conditions I treat.

Getting it right requires more than a checklist. It requires a provider who knows what ADHD actually looks like across different ages, genders, and presentations.

Your Care Team

I am Dr. Lionel Pereira, a Board Certified Child and Adolescent Psychiatrist and the founder of Serene Behavioral Healthcare. Our practice evaluates and treats ADHD across every stage of life, from young children through adulthood, through a team that includes board-certified nurse practitioners seeing patients in person and via telehealth.

Meet our full team for complete provider bios and credentials.

Conditions and Presentations We Treat

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How We Approach ADHD Evaluation and Treatment

ADHD is a clinical diagnosis, not a label based on a single behavior or a single bad report card. We take the diagnostic process seriously so that treatment is built on an accurate foundation.

Our approach typically includes:

Structured Diagnostic Evaluation

We use standardized rating scales, developmental history, and input from parents, teachers, or partners, alongside a clinical interview, to reach an accurate diagnosis.

Ruling Out Look-Alikes

Anxiety, learning disorders, sleep problems, and trauma can all mimic ADHD symptoms. Part of our job is making sure we are treating the right condition.

Individualized Treatment Planning

Depending on the patient's age, symptom pattern, and personal goals, treatment may include behavioral strategies, medication management, or both.

Careful Medication Management

When medication is appropriate, we discuss stimulant and non-stimulant options, monitor for side effects, and track things like appetite, sleep, and growth in younger patients.

School And Workplace Coordination

For students, we can provide documentation to support IEP or 504 accommodations. For working adults, we help identify practical strategies for the workplace.

Ongoing Follow-Up

ADHD management is not a one-time prescription. We reassess regularly as needs change over time.

Signs & Symptoms of Attention Deficit Hyperactivity Disorder

ADHD looks different depending on age and presentation, which is part of why it gets missed, especially in patients who are not hyperactive.

In young children, I often see:

Difficulty sitting still or waiting turns
Constant movement, climbing, or restlessness
Difficulty following multi-step instructions

In adolescents, common signs include:

Trouble organizing schoolwork, losing assignments, or missing deadlines
Daydreaming or appearing to "zone out" during class
Difficulty starting or finishing tasks, even ones they care about
Emotional reactivity or frustration that escalates quickly
In girls especially, symptoms can present as inattentiveness and internalized anxiety rather than visible hyperactivity, which is a major reason ADHD in girls is so often missed

In adults, ADHD often presents as:

Chronic difficulty with time management, deadlines, or follow-through
Losing track of tasks, appointments, or belongings
Feeling mentally restless even without physical hyperactivity
A pattern of underperforming relative to known ability, at work or in relationships
Many adults are diagnosed for the first time after a child's diagnosis prompts them to recognize the same patterns in themselves

If these patterns sound familiar, whether in yourself or your child, a structured evaluation can provide real clarity instead of guesswork. Early intervention leads to better outcomes.

Why Patients Choose Serene Behavioral Healthcare

Patients and families come to us because they want an accurate diagnosis first, not a prescription handed out after a ten-minute conversation.

Here is what sets our care apart:

Board certified providers with specialized training across the full age spectrum, from early childhood through adulthood
A structured, evidence-based diagnostic process rather than a quick checklist
Careful attention to how ADHD presents differently across genders and ages
Both in-person and telehealth options, so care fits your schedule and location
Ongoing partnership with schools, families, and patients as needs evolve

Frequently Asked Questions

How is Attention Deficit Hyperactivity Disorder actually diagnosed? Is it just a questionnaire?

A proper evaluation involves more than a single questionnaire. We gather developmental history, use standardized rating scales completed by parents and teachers (or by the patient and people close to them, for adults), and conduct a clinical interview. We also look carefully for other conditions that can mimic ADHD before finalizing a diagnosis.

My daughter isn't hyperactive, but she struggles to focus and finish her work. Could it still be ADHD?

Does Attention Deficit Hyperactivity Disorder medication stunt a child's growth?

Can adults be diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) for the first time later in life?

What is the difference between ADHD and just being disorganized?

Schedule an ADHD Evaluation

If you suspect ADHD in yourself or your child, an accurate evaluation is the first step toward a plan that actually fits. Our team is here to help you get real answers, not guesswork.

Book an Appointment or Contact Our Office to get started.

Serene Behavioral Healthcare, 1045 Elm St, Suite 204, Manchester, NH 03101