Aashish R. Parikh, MD
Staff psychiatrist, Veterans Affairs North Texas Health Care System. Assistant professor, University of Texas Medical School at Southwestern
Dr. Parikh has disclosed that he has been a speaker for Sunovion. Dr. Carlat has reviewed this article and has found no evidence of bias in this educational activity.
Over the past decade, it’s become apparent that ADHD does not suddenly end when children grow up, and that the disorder often continues into adulthood. Since 2011, I have run a clinic specializing in adult ADHD. ADHD is relatively common in adults, with conservative estimates of a 4%–5% prevalence in the adult population, equal in men and women (http://tinyurl.com/grgb5j9). However, only about 10% of adults with ADHD are receiving treatment for their condition (Kessler RC et al, Am J Psychiatry 2006;163(4):716–723).
Assessment Before doing an ADHD assessment, keep in mind that most ADHD symptoms are nonspecific and can be present in many other psychiatric disorders—or even present in people without any disorder at all. I suggest a number of useful questions to ask patients below, but note that positive answers to any of them cannot “make” the diagnosis; instead, they are clues that may (or may not) prompt a suspicion of ADHD.
When patients come into my clinic, the first thing I do is to assess their motivation. It takes significant time and energy to see a psychiatrist, especially given the shortage of practitioners and the long waits usually required. So I will ask, “Why are you coming in for an ADHD evaluation at this age? Why now? Have there been any major changes in your life recently?” Frequently, there’s a precipitating factor that prompts a patient to seek treatment, such as a promotion, increased work responsibilities or educational demands, the birth or adoption of a child, or a new marriage.
If a patient comes in and says, “I have poor attention,” I ask how long the problem has been going on. For my patients with ADHD, the most common answer is “my whole life.” Many of them have teary eyes when answering this question.
I’ll dig into patients’ education—for example, I’ll ask, “Was school a struggle for you?” They will often say yes, or they might say their problems didn’t surface until college, in which case I ask, “How long did it take you to get your degree?” Patients may say it took them many years and multiple attempts to attain it.
I like to ask about patients’ daily home life. For example, I’ll ask, “What does your bedroom closet look like?” and many will simply laugh, because it is so disorganized. I’ll also ask, “How often do you lose important things, like cell phones or keys?” and often patients will show me that they have these items tied to their waists, saying, “This is what I have to do to not lose them.”
I additionally ask about feelings of restlessness. The way I phrase this is not just, “Are you unable to sit still?” but rather, “Do you have an urge to constantly be on the go? What is it like to sit in a meeting? Are you able to stand in line at a coffee shop?” Given the growing data that ADHD may increase the risk of mortality (Barbaresi WJ et al, Pediatrics 2013;131(4):637–644), especially due to motor vehicle accidents, I will ask patients about the number of near misses they’ve had while driving.
After these initial questions, I will more systematically go through the formal list of ADHD symptoms. I don’t simply read off a list for patients to answer out loud—instead, I have them fill out the ADHD Rating Scale IV With Adult Prompts (ADHD-RS-IV) in the waiting room. Then I go through the items with them during the interview, clarifying and asking patients to expand on select answers.
After the ADHD questions, I will do a psychiatric review of systems, because mood, anxiety, and trauma-related disorders are common in patients with ADHD.
If a patient describes symptoms of depression, it may be hard to tell whether the poor concentration is due to depression or due to ADHD. I find it helpful in these situations to ask about self-esteem. If most of the patient’s depressive symptoms are related to statements like, “I feel down on myself” or, “I feel like a failure,” I am more likely to consider ADHD, because ADHD often leads to poor self-esteem due to an inability to function well (Cook J et al, Atten Defic Hyperact Disord 2014;6(4):249–268. doi:10.1007/s12402-014-0133-2. Epub 2014 Mar 26). Anecdotally, I’ve found poor self-esteem to be more common in my female ADHD patients than my male ADHD patients.
ADHD has been found to increase rates of suicide attempts (Dalsgaars S et al, Lancet 2015;385(9983):2190–2196), probably in part because people with ADHD are impulsive, and some suicide attempts are impulsive acts (Chronis-Tuscano A et al, Arch Gen Psychiatry 2010;67(10):1044–1051). The key point is to ask about suicidal ideation in all patients you are screening for ADHD.
I make sure to take a good substance use history. I specifically ask about caffeine usage (which I don’t ordinarily do when interviewing patients without possible ADHD), and find that patients with ADHD are often using multiple energy drinks throughout the day. I ask about nicotine use, and I have observed an unusual pattern in which these patients smoke a small number of cigarettes a day, such as 4 or 6, as opposed to just saying “a half pack” or “a pack.” It’s possible they are dosing themselves with cigarettes to enhance attention.
I ask about family history, because ADHD is highly heritable: “Have any of your family members been diagnosed with ADHD?” To further clarify, I ask, “Whom do you suspect has problems with attention in your family?” In terms of past psychiatric history, I’ve found that patients with possible ADHD have had poor responses to multiple antidepressants and antianxiety meds.
When I get a patient’s medical history, I spend extra time on cardiac history to screen for preexisting cardiovascular disease. I’ll ask, “Have you ever been told that there is anything wrong with your heart? Have you had fainting spells, severe chest pains, or palpitations so severe that you had to go to the emergency room?” I try to ascertain whether there is a history of sudden cardiac death in the patient’s family, which can be difficult with some patients. My highest-yield question is, “Has anyone in your family younger than 35 passed away for an unknown reason?”
If a patient has a history of documented cardiac disease, before I prescribe a stimulant, I send a prepared letter to the patient’s cardiologist, which essentially asks, “In your opinion, do you think it is reasonably safe to use stimulants in your patient?” Most of the time, the cardiologist will approve. Only a few conditions are absolute contraindications to prescribing stimulants: cardiomyopathy, prolonged QT interval, short QT interval, Brugada syndrome, Wolff-Parkinson-White syndrome, and Marfan syndrome.
Research has not demonstrated an increased risk of serious cardiovascular events in healthy young and middle-aged adults receiving stimulant medications for ADHD (Habel et al, JAMA 2011;306(24):2673–2683). A baseline EKG is not required before starting a stimulant if there is no personal or family history of cardiac disease.
ADHD is a clinical diagnosis based on a clinical assessment and history. Neuropsychological testing has not been found beneficial for diagnosing adult ADHD. In my experience, unnecessary neuropsychological testing often serves as a barrier to treatment, because of the time-consuming process of making an appointment and receiving a report. Nor is there any utility to be found in the many device-based “diagnostic tests,” such as the TOVA, CPT, quantitative EEG, and SPECT scans.
Medication treatment Before I start any medication, I run a patient’s name through my state’s prescription drug monitoring program (PDMP). After querying the system, it can be quite obvious that someone is doctor-shopping in order to get stimulants, and I will confront patients with this information; they will need to seek specialized substance abuse treatment before I will treat them. But PDMPs are useful for other reasons, too. For example, when patients can’t remember all the medications they’ve been prescribed, a search of the PDMP can be helpful; however, note that only scheduled medications will be listed.
There are two main categories of drug treatment for ADHD: stimulants and non-stimulants. Stimulants have a much larger effect size than non-stimulants, in the range of 0.9 for stimulants as opposed to 0.45 for non-stimulants such as atomoxetine (Arnold LE, J Atten Disord 2000;3(4):200–211). For this reason, I encourage most patients to start with stimulants. If they are reluctant, I will say that they are the gold-standard treatment for ADHD, that we’ve been using them since the 1940s, and that they are safe at the prescribed dosages.
Among stimulants, there are essentially two main choices: amphetamine vs. methylphenidate preparations. Although studies have not shown any difference in efficacy between the two classes, my clinical impression is that amphetamines are somewhat more effective for adults, and for that reason about 90% of my adult ADHD patients are on one of the amphetamines.
My first choice is generic Adderall IR (mixed amphetamine salts, immediate release) because it is effective, very well tolerated, and cheap. I set a target dose of 0.5 mg per kilogram of body weight, and I prescribe it twice daily, to be taken morning and noon. For the first week I have patients take 0.25 mg/kg, increasing to the target dose of 0.5 mg/kg in the second week. Methylphenidate is less potent, and its target dose is about 1 mg/kg.
Easy Pound-to-Kilogram Conversion
Divide weight in pounds by 2
Subtract 10% from the result
Example: Calculating Adderall dosing for a 130 lb. woman
Divide weight by 2: 130 / 2 = 65. Subtract 10% (6.5, but you can round down for simplicity): 65 – 6 = 59 kg. Use rule-of-thumb Adderall dosing of 0.5 mg/kg, and round up to 60 kg: 0.5 x 60 = 30 mg, prescribed as 15 mg twice daily.
Regular dextroamphetamine is interchangeable with Adderall, and has the same dosing. However, it’s generally more expensive than Adderall.
Extended-release formulations Some patients do better on extended-release medications, which yield more consistent serum levels of the stimulant. Adderall XR is my usual choice because it is generic, and the same total dose can be maintained when switching from the IR to the XR version. Although theoretically the duration of action of Adderall XR is long enough for once-a-day dosing, in my experience it must still be dosed twice daily for most patients.
In general, I avoid prescribing Vyvanse (lisdexamfetamine) as a first-line treatment because it is costly and no more effective than Adderall. Its advantages include being longer-acting, often allowing once-a-day dosing, and lower abuse potential, because it requires digestion in the GI tract before it is active. I’ve seen a lot of variability in responses to Vyvanse. When I have switched patients from Adderall formulations to Vyvanse, half of my patients have said, “This is great; it’s smooth and I don’t have a crash,” but half have said, “I want to go back on my Adderall.” I speculate this has to do with variability in how efficiently the drug is activated.
There is a subset of patients for whom Vyvanse is clearly the best choice: those who have had bariatric surgery. Whereas most stimulants require an intact stomach for absorption, Vyvanse is absorbed in the small bowel, which is preserved after such operations.
If I have a patient who has responded to a methylphenidate product in the past or who requests it for some other reason, I will generally start with the immediate-release version (brand name Ritalin) and may switch to other versions, such as Focalin IR/XR or Concerta, as dictated by response and patient preference.
Stimulant side effects In terms of side effects, I warn patients that appetite suppression is common in the beginning and that they may lose 8–10 pounds over the first several months, but that this weight loss should not persist. If appetite loss is a problem, I recommend eating before taking the medication. Insomnia can occur, but it is usually not an issue, because paradoxically sleep improves—either because of decreased bedtime ruminations, or because of symptoms wearing off due to decreased blood levels of a stimulant (“crashing”). For patients with significant insomnia, I recommend only morning dosing. If crashing becomes a problem, splitting the medication into three daily doses sometimes helps.
Irritability is a potential side effect of stimulants, but it is less common than many assume. In fact, I often see decreased irritability, since many people say the medications produce a calming effect. Irritability and increased anger are likely more common among amphetamine abusers who do not have ADHD.
One of the most common side effects of stimulants is dry mouth. Patients usually do well with oral rinses (brands include Biotene and SalivaMAX), but if they are having gingival recession, I will prescribe pilocarpine, a medication approved for xerostomia.
Non-stimulant treatments I will prescribe a non-stimulant for patients who have failed a stimulant in the past, have responded well to a non-stimulant in the past, or have recently gone through substance abuse treatment.
My first choice is Wellbutrin (bupropion), which is equally effective as and cheaper than Strattera (atomoxetine), and has the added benefit of being an approved antidepressant. Bupropion can be used for ADHD, but many doctors do not dose it high enough. In the clinical trials for ADHD, the mean daily doses were 362 mg of bupropion SR and 393 mg of bupropion XL. I typically use the XL formulation because it is difficult for patients to remember to take the second dose of the SR. I will start at 150 mg daily for one week, then 300 mg for another week, then 450 mg. I warn patients of potential side effects like sleeplessness, decreased appetite, and jitteriness. It may take 5–6 weeks to see the full benefit.
My second choice is atomoxetine (Strattera). I start with 40 mg daily for a week, then go up to 80 mg, and if needed increase to 100 mg. The side effects are similar to antidepressants, such as insomnia, sexual dysfunction, and nausea. I will wait about 6–8 weeks before declaring a non-response.
Other potential non-stimulants are alpha 2 agonists, which I have not found effective for adults, and modafinil (Provigil), which was found effective in clinical trials for ADHD in children but not in adults.