When and How Should We Adjust Treatment?

Comorbid Considerations Q&A: Treating Bipolar Disorder, Depression, Anxiety, or Autism Alongside ADHD

This Q&A for ADHD clinicians is the first in a five-part series with Dr. Anthony Rostain, a pre-eminent ADHD clinician with a primary clinical focus on complex neurodevelopmental issues including ADHD, autism spectrum disorders, learning disabilities, and social communication disorders. Here, he offers treatment recommendations for patients diagnosed with more than one condition.

By Anthony L. Rostain, M.D., M.A. Verified Updated on April 8, 2024

Comorbidity is the rule, not the exception, in most psychiatric practices. Clinicians today must possess a thorough and nuanced understanding of disparate conditions in order to effectively diagnose and treat their patients’ symptoms attention deficit disorder (ADHD or ADD).

This is the overarching principle of Dr. Anthony Rostain, professor of psychiatry and pediatrics at the Perelman School of Medicine at the University of Pennsylvania and attending and supervising psychiatrist at the Children’s Hospital of Pennsylvania and the University of Pennsylvania Health System. Dr. Rostain — who is triple boarded in pediatrics, adult psychiatry, and child and adolescent psychiatry — was interviewed recently for an Ask the Experts webinar hosted by The American Professional Society of ADHD and Related Disorders (APSARD). This is the first of five articles based on his responses to questions from Dr. Gregory Mattingly of Washington University School of Medicine about aspects of treating ADHD. This article is presented for general educational purposes, not medical advice.

Dr. Mattingly: Mood disorders, bipolar disorder, and emotional dysregulation all occur with great regularity alongside symptoms of ADHD. As a clinician, how do you balance treating your patients for ADHD and for these and other comorbid conditions?

Dr. Rostain: The majority of patients seeking psychiatric treatment arrive with not just attention deficit disorder, but also a variety of mood disorders, anxiety disorders, substance use disorders, and the like. As clinicians, we must expect that adults with ADHD — particularly those who have not ever been treated or those who have been treated for ADHD but continue to experience impairing symptoms of the disorder — will come to us with complex presentations.

For this reason, my rule of thumb is this: Complete a comprehensive history regarding every aspect of the person’s past and present functioning, as well as a thorough history of past treatments for psychiatric disorders. That is the sine qua non of good care.

[Free Download: 9 Conditions Often Linked to ADHD]

The four most common conditions diagnosed alongside ADHD are bipolar disorder, depression, anxiety, and autism spectrum disorder.

1. ADHD and Bipolar Disorder

Data from the National Comorbidity Study suggests that, among people with ADHD, almost 20% report having some form of bipolar spectrum disorder. These patients not only have inattention, impulsivity, and hyperactivity, but also the severe mood swings and/or prolonged downturns associated with bipolar disorder.

In treating patients with comorbid ADHD and bipolar disorder, clinicians have historically been concerned about the possibility that stimulant treatment might induce or exacerbate bipolar mania. Thus, a mood stabilizer, if not already part of the treatment plan, should be introduced to minimize the chances of triggering mania.

The bigger challenge, as we have come to understand bipolar disorder better, has to do with the persistent depressive states that affect patients with both bipolar disorder and ADHD. Because stimulants don’t significantly improve the mood of patients with bipolar depression, I suggest treating bipolar depression first and saying to your patient, “Once your mood is more stable and/or you’re no longer as depressed then we can address your cognitive difficulties, your inattention, your problems with sustaining effort.”

[Self-Test: Bipolar Disorder in Adults]

I am asked frequently: What is your point of view on treating patients for bipolar disorder who are already successfully using stimulant medications? Does it make sense to keep patients on ADHD medications while initiating treatment for bipolar disorder? For example, a recent trial found that children with both ADHD and bipolar who were treated for both ADHD and bipolar had the best outcomes of any patients treated for bipolar disorder.

This is important. There is no reason to stop a medication that’s been helpful when you’re trying to treat a second condition. The bipolar patients I worry about using stimulants are college-aged students and/or people who are not getting enough sleep. With that rare exception, there is no reason not to use a stimulant while you’re treating the aspect of bipolar disorder that remains a problem.

2. ADHD and Depression

Both depression or dysthymia — either longstanding low-level depression or more severe depression — present frequently in patients with ADHD. The notion now is to introduce a medication such as bupropion (Wellbutrin) initially. Once the patient shows improvement in their mood, the clinician can decide how to add a stimulant to address ADHD symptoms.

There’s no simple algorithm for adding stimulants to medications for depression. The evidence suggests that stimulants can be effective in conjunction with these medications, but it is important to watch for side effects such as cardiovascular problems, weight loss or insomnia. As long as these basic functions are monitored carefully, you can proceed safely with stimulants.

[Self-Test: Depression in Adults]

It turns out that clinicians in the depression unit here at the University of Pennsylvania are more and more inclined to add stimulants to boost effective antidepressants. It is a fascinating time to be in psychiatry as we learn that the persistent cognitive impairments and/or inattentiveness or distractibility that many patients experience with depression can be helped by prescribing stimulants as an adjuvant for treatment-resistant depression.

3. ADHD and Anxiety

I am frequently asked by residents in my clinic how to disentangle anxiety from ADHD. Truth be told, it’s very difficult to do.

Anxiety can interfere greatly with both performance and focus. Thus the first step is to probe the patient’s history to understand how anxiety presents itself. In patients with both anxiety and ADHD, the two conditions feed one another. If the patient’s anxiety is largely performance anxiety — centering on difficulties with task performance or, in the case of a prior history of ADHD, on school, interpersonal or occupational difficulties caused by the patient’s ADHD-driven lack of reliability — then my advice is to treat the ADHD first.

If, on the hand, the patient presents with obsessive-compulsive disorder (OCD), longer-standing generalized anxiety disorder, or panic disorder, then I start a treatment plan directed at the anxiety itself. Some clinicians use Atomoxetine because it addresses both ADHD and comorbid anxiety. I have also come to appreciate the use of alpha agonists for people with anxiety and ADHD, especially those who have had a bad response to stimulants.

[Self-Test: Symptoms of Generalized Anxiety Disorder]

4. ADHD and Autism

Until the DSM-5, we were not supposed to diagnose autism and ADHD simultaneously, an error that has now been corrected. For patients with both conditions, ADHD stimulant medications have an effect size slightly lower than would be observed for patients without autism, but the data is clear that treatment for ADHD is warranted. The effect size in autism patients might be 0.5 instead of 0.7 or 0.7 instead of 0.9 for different stimulant classes. Nevertheless, there is absolutely no reason not to use doses that are comparable to any other patient to start with.

As long as your patient is not having side effects, start the dosage low and increase it slowly — continuing until the patient has a clinical response. As a rule, I try both methylphenidates and amphetamines so I can judge which is more effective. In cases of patients with sensory difficulties, I sometimes use the new liquid and oral disintegrating tablet (ODT) formulations of ADHD stimulant medications.

Medication efficacy is challenging to assess when your patient cannot report well or is not able to observe the effects of medications. You need good collateral information, such as the usual teacher or parent data, and you also need to observe the patient’s performance on tasks presented in the office.