The symptoms of TS usually appear before the age of 18. If they develop afterwards, TS is unlikely to be diagnosed because the symptoms are usually less severe or are attributed to other medical conditions. Symptoms are often worse before the mid-teens and improve as the person gets older. But for about 10% of people with TS, the symptoms get progressively worse into adulthood.
Most people with TS have simple motor and vocal tics. Continual eye blinking is one of the most common simple motor tics. Others include grimacing, head jerking, shrugging, and leg tapping. Simple vocalizations can include constant throat clearing, sniffing, grunting, barking, or other noises.
Some people with TS experience more complex motor and vocal tics that involve more muscles and more complicated movements. Complicated motor tics include shrugging combined with head jerking, copying other people's movements (echopraxia), sniffing objects, touching other people, and, very rarely, self-harming behaviours such as banging the head or biting the lip.
Complex vocal tics can involve words and groups of words, including repeating other people's words (echolalia) and loud swearing and cursing (coprolalia).
Coprolalia is a symptom popularly associated with TS, but only a minority of people have this symptom. Many people with TS can control their symptoms for a few minutes to hours at a time, but it's like trying to hold back a sneeze. It must eventually come out, and it's likely to come out in a bigger way if it's delayed.
People with TS often find that their symptoms get worse when they're nervous and ease when they're relaxed or concentrating hard on something.
People with TS may also have other conditions that affect their behaviour. Obsessive-compulsive disorder (OCD) and attention deficit hyperactivity disorder (ADHD) are very common in people with TS. These additional conditions may cause more functional and social problems for people with TS than the tics caused by TS.
ADHD is characterized by poor attention span and impulsive behaviours, whereas OCD involves repetitive and intrusive thoughts or repetitive behaviours. In adults, this often involves habits like continually checking that the door is locked, making sure the oven is turned off, or endless hand washing. A typical OCD behaviour in children is touching something with one hand, then feeling like they must "even things out" by touching it with the other hand.
People with TS may also be more at risk of experiencing depression and anxiety.