context: ADHD and Tourette's syndrome are two separate conditions, but they have a few things in common. They often start around the same age, and in some cases children can have both conditions. But there are some key differences between them. It's important to get the right diagnosis for your child. The main symptom of Tourette's syndrome is repeated movements or sounds, called tics, that a person can't control. They can be simple, like constant eye blinking, sniffing, grunting, or coughing. They can also be complex, like shoulder shrugging, facial expressions, head movements, or repeating words or phrases. The tics usually happen several times each day. Sometimes, kids with ADHD can have symptoms that seem a lot like tics. They might fidget, squirm, or make random noises if they are being silly. Sometimes kids who take a type of ADHD medicine called stimulants might have tics. The drugs don't cause them, but they may make them noticeable. And they often go away on their own. Signs of both conditions tend to show up around the same age. Symptoms of ADHD can start to appear between ages 3 and 6. Most kids are diagnosed during elementary school. On average, Tourette's syndrome begins around 7 years old. And some children have both conditions. More than 60% of those with Tourette's syndrome also have ADHD. They also may have related conditions, like obsessive-compulsive disorder ( OCD), learning disorders, and depression. Researchers have found that there may be a genetic link between Tourette's syndrome and disorders like ADHD and OCD. They have a similar biology that makes them more likely to happen together. Tics from Tourette's syndrome are different from the movements or noises that kids with ADHD might make. They almost always involve fast, repeated face or shoulder movements or sounds, which happen the same way each time. Often, kids with ADHD won't have any tic-like movements. Instead, they have trouble staying focused or paying attention. They might be easily distracted or have problems staying organized. Children with Tourette's syndrome often outgrow their tics by their late teens or early adult years -- they happen less often and sometimes disappear altogether. ADHD symptoms often last into adulthood. Also, Tourette's syndrome is rare. The CDC found that about 138,000 kids in the U. S. have been diagnosed with it, while about 6.4 million have ever been diagnosed with ADHD. Researchers believe that genetics have a lot to do with both conditions. But other possible causes of ADHD might include brain injury, low birth weight, or smoking and drinking during pregnancy. Your doctor will be able to tell whether your child's symptoms belong to ADHD, Tourette's syndrome, both, or something else. There's no special test to diagnose either condition. Your doctor will ask about symptoms and when they started. He might do a blood test and medical exam to see if anything else could be causing the problem. Treatment for kids with ADHD often includes a mix of medication and behavior therapy. Stimulants are the drugs that are most commonly prescribed for the condition, but other drugs, like atomoxetine, guanfacine, clonidine, and antidepressants, can help, too. In behavior therapy for ADHD, kids learn or build on positive behaviors to replace others that cause problems. If your child has Tourette's syndrome, his doctor will likely suggest that he take medication to help with his tics. They might include some types of ADHD medicines, anti-seizure drugs, antidepressants, antipsychotic drugs that block the brain chemical dopamine, and Botox shots. Drugs don't get rid of tics completely, but they can help control them. Kids with Tourette's syndrome can also try behavior therapy. One type, called habit reversal, helps them learn to identify that a tic is coming on and then learn a new behavior to do instead. If your child has both ADHD and Tourette's syndrome, his doctor may treat the ADHD first. That may ease stress and improve attention, which can sometimes strengthen a kid's ability to control his tics.