Spring is in full bloom in the mountains of West Virginia when Joy and Kenny Johnston's son Paul, 13, bursts through their kitchen door like a superhero in a movie that only he is watching. He pauses long enough to show off his pair of muddy, mismatched sneakers, then streaks through the house in noisy pursuit of his baby sister Destiny. "She's like the Terminator!" he cries. "She never stops!"

Paul Johnston's sudden, seismic appearance barely fazes his parents. "He's a boy, an adolescent," says homemaker Joy, 37, with a sigh. But for years, as far back as kindergarten, Paul's doctors have insisted that he suffers from attention deficit/hyperactivity disorder (ADHD) Paul began taking Ritalin, a drug commonly used to treat the condition, when he was 5. When that failed to calm him, other drugs—stimulants, antidepressants, antipsychotics—followed, but nothing seemed to help. By the time Paul turned 13, he was gulping 10 pills a day—and still subjecting his family to tantrums so violent that they sometimes called the police.

In time Paul began hallucinating and hearing voices. After he was found desperately stabbing himself in the chest in 1997, the Johnstons became convinced that something drastic had to be done. "Our son was a walking drugstore," says Kenny, 41, a substitute school custodian. With the help of Peter Breggin, a Maryland psychiatrist, the Johnstons weaned Paul off almost all his pills. He is now far more stable. But because of all the school he missed during the years he was on heavy medication, Paul simply can't keep up with students his own age. In May his parents pulled him out of seventh grade, and have begun homeschooling him with the help of a friend who is a former teacher. "The drugs were supposed to help Paul stay in school," says Joy. "All they did was rob him of his education."

Paul Johnston's experience, while extreme, helps explain why Ritalin—a drug many doctors consider one of the safest and most effective on the market—is also one of the most controversial. Last year lawyers in New Jersey and Florida filed class-action suits against Novartis, the maker of the drug, which is used by an estimated 4 million American children every day. The suits charge the firm with conspiring with the American Psychiatric Association and the national advocacy group Children and Adults with Attention Deficit/Hyperactivity Disorder to boost drug sales by broadening the guidelines doctors use to diagnose ADHD. Novartis, CHADD and the APA vehemently deny the charges—and so far judges have dismissed similar suits in Texas and California, where a federal court in March found no "misrepresentation of any material facts" on the part of Novartis.

Even so, more moderate critics are also alarmed by the sharp increase in the drug's use. According to one recent study, the number of Ritalin prescriptions for school-age children has more than tripled in the past five years, with a marked rise in use by kids as young as 2 or 3—even though the U.S. Food and Drug Administration has approved the drug only for children 6 and older. That has some experts worried that medication intended for patients with a serious brain disorder is being doled out by parents too busy or impatient to devote more of their time to children who may be troublesome but have no significant clinical problems. "In this fast-paced culture, we are tempted to go for quick solutions," says psychiatrist Edward Hallowell, coauthor of Driven to Distraction, a book about coping with ADHD. "And what could be quicker than writing a prescription and taking a pill?"

The furor over Ritalin doesn't stop there: According to the U.S. Drug Enforcement Agency, illicit use of the powerful stimulant is also on the rise among high school and college students who crush the pills and snort them for an illegal high. Given all the negative headlines, it's little wonder doctors now report a backlash against the drug among some parents, says Russell Barkley, professor of psychiatry at the University of Massachusetts medical school: "Most physicians will tell you that the problem is not parents beating down the door to get Ritalin, but even persuading families to give it a try."

Concerns notwithstanding, the drug has long been embraced by the medical mainstream. Ritalin's active ingredient, methylphenidate, has been used to treat hyperactivity in children and adults for more than 40 years, and while it can cause unwanted side effects—the most common being insomnia and reduced appetite (which can slow growth in developing children)—most doctors agree that those symptoms can be managed by adjusting the dosage or switching to similar medications. Ritalin is not for everyone, says psychiatrist Lawrence Greenhill, an ADHD researcher at the New York State Office of Mental Health, but "when used at the appropriate dose level for a child who has been properly diagnosed, the medication works extremely well."

How it works remains something of a mystery. Researchers now believe Ritalin increases chemical activity in an area of the brain that controls judgment and decision making. Instead of responding to every impulse, for instance, a child on Ritalin can more easily consider the consequences of his or her actions. "It's like putting in a two-second delay in their brains," says Greenhill. Ritalin often allows kids to focus more sharply on their work, but even advocates won't call it a panacea. Sally Smith, founder of Washington, D.C.'s Lab School for children with learning disabilities, explains the drug's effect by holding up a ruler. "I tell parents Ritalin can give their child one inch [of help]," she says. "The rest has to come from them."

For a parent like Eileen LaGrotta of St. Louis, who is raising two boys with ADHD, any amount of help is welcome. In April the youngest of her three children, Matt, 9, a hyperactive third grader, thrust his foot into the path of the family's van as Eileen's husband, Rick, 48, a manager for a company that sells industrial pumping equipment, was backing out of the garage. "It was a three-quarter-ton van rolling right over his foot," says Eileen, 43, a teacher's aide. Matt wasn't seriously hurt, but for Eileen and Rick, keeping the boys out of harm's way is a full-time job. "With Matt, it's just, 'Ready, fire, aim,' " says Eileen. "He's that impulsive."

She learned about ADHD almost three years ago when her older son, Tony, now 11, was diagnosed. Tony was quiet and shy—hardly fitting the hyperactive-child stereotype. He also seemed unduly sad. When he started school, he made painfully slow progress, venting his frustration through fierce tantrums at home. Day after day he spent recess period copying homework assignments from the blackboard while his classmates, their work completed, played outside. But that changed when a pediatrician diagnosed Tony with ADHD and prescribed Ritalin. "Within a week, he was playing at recess," says his mother. "It was amazing."

It was also the beginning of a personal revelation for Eileen. Like Tony, she had been a reserved, compliant child. Dropping out of the University of Missouri, she worked as a commercial artist, a department-store salesperson, a lifeguard, a bookkeeper, a hotel reservationist. "I've had 15 employers and 25 job titles," she says. According to Sari Solden, author of Women with Attention Deficit Disorder, LaGrotta's situation was typical of the estimated 5 million women who suffer from a type of ADHD that doesn't include hyperactivity. Unlike rowdy boys, says Solden, 52, "women tend not to be diagnosed as children because they never made trouble." Instead, they are often labeled daydreamers or disorganized.

Eileen finally sought professional help and was diagnosed with ADHD in 1999. One morning that July she took her first dose of Adderall, an amphetamine used to treat the disorder. "My head was quiet for the first time in 40 years. I could hear myself think, I could decide what to think," she recalls. "It was the most amazing day in my life." With the medication and sessions with a psychologist every other week, LaGrotta has completed business and computer classes with a 4.0 grade-point average.

For kids with ADHD and their parents, the diagnosis itself sometimes brings enormous relief. Ellen Kingsley, an Emmy Award-winning former TV journalist, recalls feeling that doctors and teachers blamed her and her husband for her 14-year-old son T.K. Hirshfeld's problems at school. "We thought we were being called bad parents," says Kingsley, 49, who was also raising T.K.'s two older stepsisters, both of whom were well-behaved high achievers.

But T.K. was different. He had problems learning language skills in class and pushed kids on the playground. That led other children to shun him. "These kids take a beating," says Kingsley. "They don't get chosen to be on teams. They can become outcasts." When T.K. was diagnosed with ADHD in 1991, Kingsley decided to devote herself full-time to his care and in 2000 began publishing ADDitude, a magazine for adults and children with ADHD, from her office in Houston. Earlier this year, T.K., who takes medication and receives behavioral therapy for his ADHD, completed months of one-on-one tutoring to study Hebrew for his Bar Mitzvah. "I think he's over the hump," says his mother.

Compared with such success stories, though, the experience of Paul Johnston and his family only seems more harrowing. Paul, who began taking Ritalin in 1993, reacted badly almost immediately. "He was moody. He would not sleep. He would not eat," recalls Joy. Even so, the Johnstons felt they had little choice but to keep Paul on medication. In fact the principal of his school, Joy says, had threatened to call Child Protective Services unless they got medical help to stop their son's disruptive behavior in class.

Soon, Paul was behaving just as badly at home. "Little things would set me off," he says. "If I was trying to put together a model and I couldn't fix it, I'd get mad. I'd destroy it." The Johnstons took him to no fewer than 14 doctors. Most upped his Ritalin dosage, while others prescribed antidepressants. After Paul started hearing voices in 1997, he was put on Risperdal, an antipsychotic that can have permanent side effects, including involuntary tics. "The boy was falling apart," says Kenny.

So was the Johnstons' marriage. "I had had my fill of it," says Kenny, who drank heavily to escape the tension. But a crisis would bring him and Joy together to save their son. On Sept. 19, 1997, Paul's older sister Vickie, now 16, found him in his room brandishing a bloody knife: The boy had slashed himself in the chest several times. In all, Paul made four visits to a psychiatric crisis center before his parents consented to commit him to a long-term facility in Barboursville, W.Va., last year.

Paul stayed there until his mother, searching the Web with a borrowed laptop, learned about Peter Breggin, the controversial Maryland psychiatrist whose fierce criticism of Ritalin helped to inspire the class-action suits against Novartis. "I'm seeing kids like him who are on five or more psychiatric drugs who have substantially nothing wrong with them," says Breggin, 65. "What they really need is better discipline at home."

Breggin's contention that no child should take Ritalin for ADHD is accepted by only a slim minority of medical experts. In fact the National Institute of Mental Health has published study findings that support stimulant medication, along with behavioral therapy, as the best treatment for ADHD. And for the 30 percent of people who don't respond well to the ADHD medicines currently on the market—some parents say they turn their kids into "zombies"—new drugs are in development with the potential to deliver better results.

But the Johnstons are resolved to try a drug-free solution. Joy and Kenny are doing their best to provide a disciplined environment at home and are pleased with Paul's progress, although the boy's erratic behavior—he recently became enraged after his father happened to touch him—can still be worrisome. "He's come a long way," says Kenny, "but he's still got a long way to go."