ADHD’s name has changed before. What could be next?

Today, we know ADHD, or attention-deficit hyperactivity disorder, as the official name for the condition that causes symptoms like difficulty focusing, impulsivity, and paying attention. But before there was ADHD, there was attention-deficit disorder, or ADD. This was used from 1980 up until 1987, when it was renamed ADHD.

And now, a new term is popping up: EDHD, or energy deficit hyperactivity disorder. EDHD isn’t an official medical diagnosis. Instead, it’s a theory that researchers are investigating to understand how exactly ADHD affects the brain and why symptoms may vary from one day to the next.

So will ADHD’s name change again? And why does it even matter that we all use the same terminology? Understood explores the many names of ADHD, why consistency is important, and how new research could change the way we think about ADHD.

Quick take

• The term ADD was introduced in 1980 to describe a condition that caused trouble focusing and forgetfulness.
• In 1987, ADD was renamed ADHD. That’s still the correct term and official medical diagnosis today for people experiencing inattention, hyperactivity, and impulsivity.
• New research published in 2026 proposed EDHD as a theory to investigate whether less energy in the brain can cause ADHD and affect how symptoms show up daily.

How ADD became ADHD

Recognition of the symptoms of ADHD may go back to the fifth century B.C. The ancient Greek philosopher and physician Hippocrates was one of the first to document a condition marked by restlessness and trouble focusing.

In modern times, symptoms of ADHD were first explained in The Diagnostic and Statistical Manual of Mental Disorders, Second Edition (DSM-II) in 1968. These symptoms were described as “hyperkinetic reaction of childhood.” Researchers believed it caused short attention spans and difficulty sitting still in kids, but that the symptoms would eventually go away when children became adults.

History of ADD

In 1980, researchers renamed the condition ADD. This was a breakthrough. For the first time, researchers acknowledged that there were people who had trouble focusing but didn’t experience any issues with activity levels.

Health care providers could choose from two subtypes of ADD when making a diagnosis:

• ADD with hyperactivity: This meant that you had trouble focusing and difficulty sitting still.
• ADD without hyperactivity: This meant that you had trouble focusing but didn’t experience any issues with excessive motor activity, like fidgeting or restlessness.

History of ADHD

In 1987, researchers realized that inattention and hyperactivity weren’t two separate categories, but symptoms of the same condition. “The name changed from ADD to ADHD after years of research that found hyperactivity and impulsivity were key symptoms that people with attention difficulties also experience,” says Kristin Carothers, Ph.D., a licensed clinical psychologist.

The original term “ADD” left out hyperactivity as a primary symptom. To be more inclusive of all symptoms, researchers changed ADD to attention-deficit hyperactivity disorder, or ADHD, which is the official medical diagnosis and correct terminology we use today.

Subtypes of ADHD

In 1994, three subtypes or presentations of ADHD were introduced under the ADHD umbrella. These appear in the DSM-IV:

• Inattentive: People with this subtype experience symptoms like trouble paying attention, difficulty concentrating on tasks, or getting distracted easily.
• Hyperactive/impulsive: People with this subtype often feel the urge to move around, get fidgety, or make decisions without thinking first.
• Combined: The most common ADHD subtype, and a combination of inattentive ADHD and hyperactive/impulsive ADHD. People with this subtype experience a mix of inattention, hyperactivity, and impulsivity symptoms.

The three subtypes of ADHD make diagnoses more accurate and inclusive. They help health care providers recognize symptoms in people whose ADHD is often overlooked, like girls, adults, and people of color. Knowing what subtype of ADHD you have can help you and your health care provider figure out which treatments and strategies may be the best fit.

What’s the difference between ADHD and ADD?

ADD is no longer considered a medical diagnosis. But that hasn’t stopped many people from using ADHD and ADD interchangeably, especially since the terms are so similar.

It’s important to remember that the hallmark symptom of ADD — getting distracted or having trouble focusing — is still part of the diagnosis. It’s just now categorized under the umbrella term of ADHD. Using the correct terms, especially when replacing an outdated term, is important for many reasons, Carothers explains.

“The use of the term ADD is no longer appropriate because the DSM requires that we all use the same language to discuss disorders and presentations,” she says. “Using similar terminology, descriptions, and understanding of a disorder helps us ensure that we are finding and treating specific symptoms.”

Even though the term has changed, you might still hear people use “ADD” in conversation, like, “I’m so ADD” or “That’s so ADD.” Using “ADD” to describe having a forgetful moment can downplay the challenges that people with ADHD actually experience. Using the correct term — and only in the context of a health condition — helps reduce myths and stigma around the disorder and shows respect to the people living with ADHD.

What is EDHD?

As more studies on ADHD are conducted, researchers are trying to better understand how ADHD affects the brain and what science can do to support people living with the condition. A 2026 study published in Neuroscience & Biobehavioral Reviews introduced the term EDHD, which stands for energy deficit hyperactivity disorder.

It’s important to note that EDHD is not a medical diagnosis or a new name for ADHD. EDHD is a new theory that may help us understand how exactly ADHD may be linked to changes in brain functioning and why these symptoms can look different from one day to the next.

For decades, researchers have believed that ADHD is a wiring issue in the brain that makes it difficult to focus. But the research on EDHD says otherwise. It proposes that people with ADHD experience a shortage in how much energy they have to do cognitive tasks — like paying attention, making decisions, or controlling impulses.

Your brain needs a large amount of chemical energy to stay focused and complete tasks. People with ADHD may experience an imbalance of energy. When this happens, the prefrontal cortex (the part of the brain that’s responsible for things like decision-making, memory, and emotional regulation) may run out of energy faster when doing hard tasks.

EDHD research is important because it highlights a common experience among people with ADHD, explains Keona J. Wynne, Ph.D., MBE, senior research manager at Understood. “It gives us a structured way to think about why certain tasks can be more taxing than others for people with ADHD,” she says.

Further study into EDHD could change how we as a society view ADHD. Many people misjudge the condition, seeing it as a behavioral issue or a lack of discipline. But EDHD research shifts the focus from an individual behavioral problem to a chemical energy issue in the body.

While the research on EDHD is still new, “the next step is to move from theory to practice,” Wynne says. That means investigating the brain’s capacity further, and working with researchers in other fields, like neurobiology or workplace psychology, to study how the brain processes energy.

“It’s exciting because EDHD gives researchers further questions to look into, like which tasks are best to help ADHD brains stabilize?” Wynne says. “And how can schools and work be better structured to help reduce the load on the brain?”

Will the name ADHD change… again?

The last change to ADHD was in 1994 when three ADHD subtypes, or presentations, were added to the DSM-IV. There are no plans to make any more changes or add EDHD to the mix. “The lead researcher was clear that EDHD is solely a research framework,” Wynne explains, adding that it is not a “diagnostic” criterion.

That said, new subtypes of ADHD could be added. But only if research backs up the need to do so. “I don’t believe that ADHD will be renamed unless the field of clinical child psychology overwhelmingly finds research to support the necessity for a name change,” says Carothers. “However, new subtypes of ADHD could be generated if there are independent research groups who find the presence of a new set of symptoms based on data.”

So, as of now, ADHD will keep its name. But new research and data may expand our understanding of ADHD to better support people living with it.

This story was produced by Understood and reviewed and distributed by Stacker.