Louisa Lewis saw the signs long before an official diagnosis.

Lewis saw symptoms of her son’s attention deficit hyperactivity disorder — ADHD — when he was just 3 years old. She faced Joshua’s middle-of-the-night activity sessions years before he started kindergarten.

Lewis, who is chief executive officer of Positioned with Purpose, an Upstate South Carolina-based organization offering support for pregnant and parenting teenagers, regularly works with teen parents. She also has experience working with special-needs students.

“I knew the symptoms and I knew we had an issue,” Lewis said.

According to the Centers for Disease Control, as of 2010, approximately 8.4 percent or 5.2 million children ages 3 – 17 have been diagnosed at some point with ADHD. For some, symptoms of the disorder and the medications prescribed to treat it can mask other conditions that may be at the root of attention deficit problems.

Lewis’ son, Joshua, 9, has responded to medication and Lewis has learned coping skills to help deal with Joshua’s ADHD. He has also seen a developmental specialist who confirmed his diagnosis.

But Frank Barnhill, a Gaffney family physician and author of “Mistaken for ADHD,” said millions of children diagnosed with ADHD are misdiagnosed. His book arose from firsthand experience with patients who suffered from other conditions whose symptoms mimicked ADHD.

“It’s been at least 12 years,” he said. “I noticed an increase in the number of children whose parents were bringing them in because they were not responding to their ADHD medications. Some had been on three, four, five ADHD stimulants. Some were on anti-psychotics. Approximately two out of every 10 children I evaluated for failure to respond to their medications had something else.”

Barnhill isn’t a naysayer about the existence of ADHD or the use of medications to treat it, but he does contend that many children should be treated for something else entirely. In girls, thyroid disease may be at play, he said, while in boys, impulsive behavior may be due to discipline problems or even bipolar disorder. Barnhill said children sometimes have hearing or vision problems, depression, sensory integration disorders, sleep issues, seizures or a number of other possibilities that result in ADHD-like symptoms. Some children are responding to circumstances such as bullying, abuse or divorce.

“A lot of doctors are not trained to make the diagnosis of ADHD,” Barnhill said. “We are too fast to label a child. As a society, we are too fast to throw pills out.”

Joel Sussman is a physician and clinical director for Palmetto Associates for Scholastic Success located in Columbia. His practice is an evaluation clinic for children, teens and adults with attention deficit disorders.

Sussman said a comprehensive evaluation is needed to make an accurate diagnosis. He has also found that lifestyle changes can make a big difference in children.

“I try to rule out some other things that seem like ADHD but are not,” he said.

Sussman said limiting video games, making sure children get adequate down time and sufficient sleep can be critical. And for many, getting outside to play can make a tremendous difference. Heavy use of electronics — video games and other screen time, as well as texting for teens — wasn’t an issue in generations past, but today’s children face problems with sleep, mood and anger management as a result, he said.

“It’s a big, big issue nationally,” he said. “People under 30 grew up with video games. I spend more time talking about lifestyle than medicines — 20 to 1.”

Barnhill said some conditions will respond to medications often prescribed to treat ADHD. That may be especially true for children with depression or sleep problems.

“If you put them on an amphetamine, they are going to get better for a while,” Barnhill said. “A Texas study said as many as 20 percent of kids with sleep-disordered breathing — problems with tonsils or adenoids — had been misdiagnosed with ADHD. Sleep apnea produces a lot of the symptoms of ADHD. When you can’t sleep well at night, you have a lot of the symptoms of ADHD.”

Barnhill said an evaluation for ADHD should include more than a questionnaire completed by teachers and parents.

“I won’t put a child on ADHD medication the first time I see them, but 90 percent of the kids I see, that’s what has happened,” he said. “They are placed on a drug the first time they are seen. The kid gets put on a drug that has multiple side effects. We are over-diagnosing based on the fact that we are not doing a good job evaluating these kids. You’ve got to give the kids the benefit of the doubt. I put children on ADHD medications all the time but I do an adequate work-up.”

Barnhill said a diagnosis of ADHD requires that the behavior occur in more than one environment — school, along with home, church or another setting.

“If it occurs only at school, it’s unlikely to be ADHD,” he said. “Second, the behavior has to clearly cause the child a disability.”

Sussman said attention deficits can be overdiagnosed by those who use a checklist without a full evaluation. Conversely, it can be underdiagnosed in children who are “day dreamy.”

“If they aren’t hyperactive, they aren’t diagnosed quickly,” he said.

Gifted children often get bored in the classroom, according to Barnhill.

“That can look like ADHD,” he said.

For children, like Lewis’ son, who do have ADHD, other conditions may still need to be addressed.

Pam Erwin, learning differences coordinator at Shannon Forest Christian School in Greenville, said 80 percent of the children in the school’s learning differences program also have attention deficit disorder.

“They can learn,” she said. “They just need a different way.”

Erwin said although she does see a great deal of ADHD, she agreed that a subjective diagnosis can sometimes overlook other causes.

“It’s amazing,” she said. “Often it is misdiagnosed.”

Erwin works with students who have a wide variety of learning differences, including ADHD, processing disorders and other conditions.

“We’ve had really wonderful results,” Erwin said. “There is much hope. That is something I always want parents to know, no matter what the disability or the differences. There are so many avenues now. We know a lot more. We’ve come a long way. Parents play a key part. If we all work together, that child has great opportunity for success.”

For Lewis, part of helping her son has come in a doctor’s recognition that she, too, has attention deficit disorder. Keeping lists and a detailed schedule help her stay on task and Lewis uses those tools to help her son as well. And, she said, she relies on her faith and her love of her child to help see her through the difficult days.

“Joshua keeps me going and focused because he has a lot of hope and he is very positive about it,” she said.

Could your child have ADHD?

Does your child have symptoms of attention deficit hyperactivity disorder?

• An interactive ADHD checklist is available online at http://www.cdc.gov/NCBDDD/adhd/diagnosis.html.

• For more information and additional resources, visit www.drjoelsussman.com and mistakenforadhd.com.