ebook_ADHD2019_engl.

The World Federation of ADHD Guide 105 ADHD + tics Comorbid tics may sometimes be worsened by stimulants. This is not inevitable, and stimulants are sometimes useful even for the hyperactivity seen in Tourette’s syndrome. Guanfacine and clonidine are alternatives, since both, have demons- trated to reduce tics in addition to their effectiveness in ADHD. 30 Atomoxetine is also an option which appears less likely to exacerbate tics than stimulants. Where guanfacine, clonidine and atomoxetine are ineffective at reducing the tics and they continue to cause significant psychosocial impairment or where methylphenidate, whilst effective for the core ADHD symptoms, is exacerbating tics (and where a dosage reduction does not lead to an improvement), the use of a tic-reducing me- dication either as a monotherapy or in parallel with ADHD medication (e.g. aripi- prazole, risperidone, pimozide, tiapride, SSRI’s) seems to be indicated. Some drug interaction checkers warn against the combination of stimulants with the alpha- -2-agonists guanfacine and clonidine for possible heart rhythm problems. In ge- neral, the risk would appear to be low, however particular care should be taken in cases of pre-existing vulnerability; i.e. where there is personal or family history of arrhythmias, cardiac malformations, or sudden unexpected death. 31 Also, the risks for rebound hypertension after a sudden stopping of the alpha-2-agonists when given alongside a stimulant may be increased and therefore due care should be exercised with slower tapering of the alpha-2-agonist should it need to be stopped. Behavioural therapy may also be helpful for tics and obsessive symptoms. ADHD + autism spectrum disorder It is always appropriate for these, usually complex, cases to be seen by a multidisci- plinary team of specialist services. There is little trial evidence, but we suggest that where ADHD is comorbid with autism, a trial of medication for the symptoms of ADHD should be considered. Medications should be started at the lowest practi- cal dose and titrated slowly and carefully as these children are more likely to suffer from adverse effects, even at low doses. Stimulants are often the most helpful with the strongest evidence for methylphenidate. Atomoxetine, clonidine, guanfacine, and even risperidone and aripiprazole may have their place. Behavioural therapy, targeting the ADHD symptoms, is also widely applicable. ADHD + substance misuse There is little in the way of research evidence to guide clinicians when treating those with ADHD and an established substance-misuse disorder. Treatment plans should address both disorders and should include psychosocial interventions ai- med at reducing substance misuse and preventing relapse. There are indications that effective treatment of core ADHD symptoms may enhance effective treat- ment of substance misuse. Pharmacological therapies for ADHD should be star-