Clonidine (Catapres) & Tenex (Guanfacine):
Clonidine and Tenex are not very good as single drugs used by themselves to treat ADD. Where they find their role is alongside another drug, used to enhance the effect or modify the side effects of the primary medication. The reason for this is that while they do help certain children with ADD, they do so in a less comprehensive way than most other ADD drugs do. Specifically, these medicines can reduce impulsivity dramatically, but they do not improve learning, attention span, task persistence, distractibility, or fidgeting.
These two very similar agents were originally developed to treat high blood pressure in adults. Their main chemical action is to boost the secondary effects of adrenaline (“alpha-2”) in the brain. In childhood, however, they have been shown to also help Sleep Disorders, Tic Disorders (including Tourette’s Syndrome), and ADD. Clonidine is actually used more frequently in children as sleep medicine than it is for ADD. It has strong sedative properties and is non-addictive. This makes it preferable to many of the sleep medicines used in adults, and so it has been used for many years to treat a variety of pediatric sleep disorders. For controlling tics it is one of the best medicines we have.
The two main side effects of these medicines are, not surprisingly, excessive tiredness or sleeping and dizziness from low blood pressure. Tenex has less sedative effect than Clonidine, so is less likely to cause tiredness, but is also less useful as a sleep aid. Neither of these medications has much impact, good or bad, on depression or anxiety.
The most common justifications for using Clonidine in combination with another ADD medicine are as follows:
- To aid an ADD child who has trouble falling asleep at bed time, whether this is due to medications which are otherwise helping or due to the ADD itself.
- To reduce tics in a child with both ADD and a tic disorder, particularly if his or her ADD medicine has worsened the tics.
- To reduce impulsivity even further in a child who has responded to another ADD medication but remains very impulsive.
These two drugs are often also used in a situation with a very aggressive and/or violent child. Clonidine and Tenex are frequently effective in reducing violent/aggressive behaviors. However, these are NOT typical characteristics of ADD. When a child has such behaviors in addition to ADD, they often don’t respond to “routine” ADD medications, indeed stimulants in particular often make them worse. While use of Tenex or Clonidine to control the behaviors may be appropriate, at the same time one should try to determine WHY the behaviors exist, rather than just “chalking them up” to the ADD.
Finally, it should be noted that Clonidine is NOT the same medicine as Klonopin (Clonazepam). While the names sound very similar, Klonopin is actually an anti-seizure medicine more closely related to Valium than to Clonidine, and it has no role in ADD treatment.