Pharmacological treatment options for ADHD and co-morbid disorders

Brief guide to treatment options

Pliszka et al. (2000a and 2000b) have published 2 papers which draw on expert consensus methodology to develop evidence-based consensually agreed-upon medication treatment algorithms for ADHD with and without comorbid conditions. Detailed guidelines, which are of immense interest clinically, are offered for implementing the chosen treatment strategies and should result in a more standardised approach. The treatment algorithms and information relating the dosing tactics for a number of medication options can be accessed via (http://www.dshs.state.tx.us/mhprograms/adhdpage.shtm). The original algorithm for pharmacotherapy of ADHD has since been updated (Pliszka et al, 2006).

Stimulants continue to ameliorate the symptoms of ADHD in the presence of other co-morbid psychiatric disorders and may even show a positive benefit on both (e.g. ADHD plus conduct disorder or ADHD plus anxiety disorder) (Greenhill et al, 2002).

See also Remschmidt by the Global ADHD working Group (2005) for consensus statement on current best practice in the treatment of ADHD and treatment algorithms for ADHD alone and in combination with common co-morbidities such as depression, conduct disorder and tics.

ADHD and conduct disorder

ODD or conduct disorder co-exist with ADHD in ~35% of children. As the conduct disorder is often secondary to the ADHD, it is suggested that the ADHD is treated first. Additional parent behaviour management and/or Cognitive Behaviour Therapy (CBT) may be helpful. The American Academy of Child and Adolescent Psychiatry's practice parameter for the use of stimulant medications in the treatment of children, adolescents and adults (Greenhill et al, 2002), recommends the addition of a mood stabilizer or alpha agonist (e.g. clonidine) to the stimulant medication if aggressive outbursts remain a problem despite the improvement in the core ADHD symptoms. Where aggression is severe, pervasive and persistent and the child or adolescent is thought to be a danger to himself and or others, it may be justifiable to add in an atypical neuroleptic e.g. risperidone 0.5mg daily to the stimulant. See also The Children’s Medication Algorithm Project website (CMAP) (http://www.dshs.state.tx.us/mhprograms/adhdpage.shtm).

ADHD and anxiety

The coexisting association between ADHD and anxiety disorder is ~ 25%. If symptoms are not improved by a trial of stimulant medication, then additional psychological intervention should be considered. Atomoxetine may chosen as a first choice mediaction for ADHD with comorbid anxiety (Sumner et al, 2005). An SSRI can also be added to a stimulant as treatment for anxiety (Pliszka et al 2006). See also The Children’s Medication Algorithm Project website (CMAP) (http://www.dshs.state.tx.us/mhprograms/adhdpage.shtm).

ADHD and tics

Although tics may be exacerbated by stimulant medication, this is not always the case. If this occurs, in the first instance the dose of stimulant should be reduced. Alternatively, consideration can be given to using the stimulant alongside a second medication which aims to reduce the tics e.g. risperidone or clonidine. It may be necessary to involve a tertiary centre. Pimozide or haloperidol can be added to a stimulant but only after failure of several atypical antipsychotics (Pliszka et al 2006). See also The Children’s Medication Algorithm Project website (CMAP) (http://www.dshs.state.tx.us/mhprograms/adhdpage.shtm). Atomoxetine may prove be a useful alternative to stimulant medication in these children.

ADHD and Autistic Spectrum Disorders (ASDs)

The literature in this area is sparse. Taylor et al (2004) suggest consideration of a trial of methylphenidate or perhaps clonidine, atomoxetine or risperidone, again with the early involvement of a tertiary centre.

ADHD and substance misuse

Effective treatment of core ADHD symptoms may enhance effective treatment of substance misuse but there is little research evidence to guide the clinician. Consideration should be given to modified release forms of methylphenidate e.g. Concerta XL, Equasym XL, as there is less potential for abuse. Bupropion and atomoxetine are possible useful alternatives to stimulants in this patient group.

ADHD and depression

The coexistence of ADHD and mood disorders is ~ 18%. Treat whichever disorder is the most severe first then add treatment for the second disorder if monotherapy does not result in remission of both disorders (Pliszka et al 2006). A selective serotonin re-uptake inhibitor (SSRI) e.g. fluoxetine may be added to methylphenidate when treating ADHD and co-morbid depression. For further information consult the CMAP website (http://www.dshs.state.tx.us/mhprograms/adhdpage.shtm).

N.B. Advice regarding antidepressant use in adolescents has been rapidly changing recently and clinicians are advised to update themselves on the current position before prescribing. See NICE guideline on depression in Children and young people ( www.nice.org.uk/)

Useful web-based sources of information on pharmacological treatment of ADHD and co-morbid disorders