An Illness That's Not
Just for Kids Anymore

A well-dressed executive is sitting in a meeting listening to her boss talk. Except she isn't really listening. Over the course of 30 seconds, more than two dozen images and sounds flash through her mind. When the boss asks for her thoughts, she looks at him blankly. Her co-workers stare.

"Ann?"

Ann, the fictitious subject of a glitzy ad campaign by Eli Lilly & Co and WebMD Corp., is the new face of attention deficit/hyperactivity disorder, that infamous condition long associated with unruly kids. For decades, doctors believed that children outgrew ADHD in adolescence. But researchers are convinced that distracted and disorganized adults may suffer from the same affliction. By one estimate, two-thirds of children with ADHD don't outgrow the disorder, leaving 5% of adults suffering from it.

Enter drug companies, who are starting to see a big opportunity to expand the market for ADHD drugs, which, according to IMS Health, which tracks prescriptions, is now over $2 billion. Lilly's Strattera is the first medication approved by the U.S. Food and Drug Administration for treating adults with the condition; it came on the market in January. Shire Pharmaceuticals Group PLC, of England, expects approval early next year to market Adderall XR to adults. GlaxoSmithKline is considering seeking approval to market Wellbutrin XL for adult ADHD. Wellbutrin is a widely known antidepressant but some doctors are already prescribing it for ADHD.

But diagnosing grown-ups with the disorder is tricky because they often have different symptoms than kids. "If you give them a checklist that says, 'runs about and climbs,' it's not germane to adults," says Lenard Adler, an associate professor of Clinical Psychiatry and Neurology at NYU School of Medicine.

Instead, hyperactivity in kids shifts to an inner restlessness as they grow up. Adults with ADHD have problems "with organizing their life around deadlines," says Russell Barkley, a longtime ADHD researcher at the Medical University of South Carolina. "If you're five-years old, time management is not an issue for you. At 25, it's a major issue." Dr. Adler, in conjunction with the World Health Organization, has developed a questionnaire to help doctors determine whether an adult patient has ADHD.

Despite the difference in symptoms, many adults tend to get diagnosed when their kids do. "All of a sudden you look at yourself and you say, 'Good Lord, I satisfy nine out of 10 of these criteria,' " says Maureen Nolan, a 50-year-old mother of two in Decatur, Ga. She is now a coach for ADHD sufferers, helping them with such problems as organization and managing time.

Uncontrolled ADHD can have serious consequences for both children and adults. "An impulsive child might take a bike and jump over a plywood ramp. An adult might go 85 miles per hour on a highway because he's late to an appointment," Dr. Barkley says.

Studies of adults with ADHD, funded by the National Institute of Mental Health, have found that they were far less likely to graduate from college (5% of the ADHD sufferers, versus 35% in a control group in a study based in Milwaukee), suffer depression (27% versus 4% of 20-year-olds in a control group), and far more likely to be judged by bosses to be "fair to poor" performers at work.

ADHD is a famously controversial ailment. It's characterized by extreme problems with attention and planning, and a lack of normal inhibitions. Some, but not all, children with the disorder are hyperactive, particularly boys. The symptoms must be present from a young age -- there's no such thing as late-onset ADHD -- and they must pose impairments. The disorder has a strong genetic link, says Thomas Spencer, assistant director of pediatric psychopharmacology research at Massachusetts General Hospital.

Some critics over the years have argued that ADHD isn't really a disorder at all, or if it is, it's widely over-diagnosed in children. The same questions are likely to arise in adult diagnoses. But despite the public controversy, the U.S. Surgeon General, American Medical Association and American Psychiatric Association, among others, recognize ADHD as a disorder.

Most medications for ADHD, including Ritalin, are stimulants. Paradoxically, they calm down the hyperactive and heighten attention among the inattentive by "waking up" parts of the brain that mediate attention, an effect that can be seen in brain scans. Some doctors, however, say they feel worried giving stimulant medication to adults who have ADHD and substance-abuse problems.

The medication that Shire is seeking approval to market for adult ADHD, Adderall XR, is a stimulant reformulated to last up to 12 hours. Side effects can include decreased appetite, stomachache, difficulty falling asleep and, rarely, quick mood changes. People with high blood pressure, glaucoma and hyperthyroidism shouldn't take Adderall XR.

Unlike the stimulants, Strattera isn't a controlled substance, a class of drugs tightly regulated to prevent abuse. Patients taking stimulants often have to return to a doctor's office every time they need a refill, but with Strattera, they don't have to do that. But side effects can include insomnia, nausea, decreased appetite, constipation and sexual dysfunction. Strattera must build up in the body, and can take a month to reach full effectiveness. Stimulant medications, on the other hand, work rapidly, within an hour or two.

Cassaundra Adler, a 39-year-old Minneapolis financial adviser with ADHD, could be impulsive, at times telling co-workers their ideas were stupid. Taking Strattera and an antidepressant, she says, made her more productive and less edgy. "It's helped a lot with relationships," she says. "You're just calmer and not so crass."

Not all adults like the effect of medication, however. Dr. Barkley tells of a patient he treated in Massachusetts, a poet who said that Ritalin helped her balance her checkbook and get her children to school on time. But she thought the poetry she wrote while on it was boring -- so she would go off the medication to write.

Write to Robert McGough at bob.mcgough@wsj.com and Patricia Callahan at patricia.callahan@wsj.com