October 23, 2023

Safety and efficacy of long-term use of guanfacine for adults with ADHD

Guanfacine extended-release(GXR) is a non-stimulant α2A-adrenergic receptor agonist, approved worldwide for ADHD in children and adolescents.

A Japanese research team set out to explore the long-term administration of once-daily GXR in adults with ADHD over a year of treatment. Their primary objective was to evaluate the safety, and the secondary objective was to evaluate efficacy.

This was an open-label trial. Open-label trials are the opposite of double-blind trials. In a double-blind trial, neither the researchers nor the participants know what treatment they participants are receiving. In an open-label trial, on the other hand, both the researchers and participants know what treatment the participant is receiving, which can introduce significant bias. These studies are therefore at the lowest rung in the evidentiary base.

It is worth noting, however, that the risk of bias would be primarily for efficacy, and the primary aim of the trial was to evaluate safety.

The trial was funded by the manufacturer, but preregistered, a way of assuring that results would be released regardless of the outcome.

The study population consisted of 191 ADHD patients 18 and older at 71 locations in Japan. There was no control population. The 50-week flexible titrated dosing treatment period was followed by a 2-week period over which doses were gradually reduced, and then a one-week follow-up period. That means the trial covered an entire year. Of the enrolled patients, 67 dropped out, mostly due to adverse events, leaving 124 patients after the trial.

A total of 830 treatment-emergent adverse events (TEAEs) were reported by 180 patients. One in five patients (34)discontinued treatment due to adverse events. The most commonly reported adverse events were somnolence, thirst, nasopharyngitis, decreased blood pressure, postural dizziness, bradycardia (abnormally slow heartbeat), malaise, constipation, and dizziness. Except for nasopharyngitis, all were considered related to the medication. There were two serious adverse events, one unrelated to the medication, the other a supraventricular tachycardia (abnormally fast heart rhythm arising from improper electrical activity in the upper part of the heart) in a patient simultaneously medicated for a preexisting condition. The patient recovered after treatment and discontinuation of GXR.

The main TEAEs resulting in Discontinuation were somnolence (nine patients), blood pressure reduction (eight patients), malaise (six patients), and bradycardia (four patients, with only one case considered severe), and postural dizziness (three patients) or dizziness(three patients).

Significant reductions in ADHD scores and improvements in executive functioning were measured across the study population following a year's GXR treatment. Again, this was not the primary aim of the trial, and double-blinded randomized controlled trials are the gold standard.

The authors concluded that "there were no new or unexpected safety concerns" and "patients who received dose-optimized GXR had improvements in multiple aspects of ADHD, including symptoms, QoL [Quality of Life], and executive functioning," but acknowledged, "There was a potential for observer bias because of the open-label nature of the study, and the findings may not be representative of real-world settings because patients with psychiatric or cardiovascular comorbidities, which are common in patients with ADHD, were excluded. In addition, there was a potential bias favoring safety and efficacy for continuing patients because those who discontinued owing to adverse events or lack of efficacy were not eligible for inclusion."

Akira Iwanami, Kazuhiko Saito, Masakazu Fujiwara, Daiki Okutsu, and Hironobu Ichikawa, "Safety and efficacy of guanfacine extended-release in adults with attention-deficit/hyperactivity disorder: an open-label, long-term, phase 3 extension study," BMC Psychiatry(2020), https://doi.org/10.1186/s12888-020-02867-8.

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New Expert Guidance on "Deprescribing" Stimulants for Adults with ADHD

The Background: 

Over the past two decades, diagnostic rates for adult ADHD have roughly doubled, and stimulant prescriptions in the United States skyrocketed by more than 50% between 2012 and 2023, particularly among girls and women. While these medications help many individuals manage their symptoms, a landmark 2026 article published in European Neuropsychopharmacology tackles an important question that is rarely discussed: When should doctors and patients consider stopping them?  

The Discussion: 

To answer this, the American Society of Clinical Psychopharmacology (ASCP) gathered a task force of 45 international experts spanning 12 countries. Through a rigorous evaluation process, they reached an overwhelming agreement on a framework for "deprescribing", the planned, supervised reduction or cessation of a medication. Here are the core insights from these ground-breaking guidelines and what they mean for adults navigating long-term ADHD treatment.  

When the Treatment Isn’t Yielding Benefits 

One of the most straightforward reasons to consider stopping a stimulant is if it simply isn’t doing its job. The task force agreed that if a patient does not experience an optimal response, measured by actual symptom reduction, improved daily functioning, and a better quality of life, even after trying a high, optimized dose, it may be time to step back and look at alternative options.  

Sometimes, the issue goes back to the initial evaluation. The criteria for diagnosing ADHD have expanded over the years, and brief psychiatric evaluations can occasionally lead to diagnostic inaccuracies. If a thorough reevaluation reveals that the original ADHD diagnosis was incorrect, the expert consensus is clear: stimulant deprescribing is appropriate unless another stimulant-responsive condition is evident. Furthermore, if a patient develops a persistent tolerance to the drug that cannot be resolved by safe dose adjustments, a temporary taper or drug holiday may be recommended.  

When the Risks to Health Outweigh the Rewards 

Our bodies and health needs naturally shift over time, meaning a medication that worked safely years ago might pose a threat to your health today. The experts concluded that deprescribing should be heavily considered if stimulants exacerbate a concurrent medical or psychiatric illness. For example, although rare, stimulants can unintentionally trigger mania or psychosis in adults with unstable or unrecognized comorbid bipolar disorder.  

Physical health developments are equally critical. If an adult develops a newly arising or unstable cardiovascular condition, such as a cardiac arrhythmia, ischemia, or cardiomyopathy, the risk-benefit balance changes dramatically. Additionally, if severe side effects occur that cannot be managed by reducing the dosage, or if dangerous new drug-drug interactions emerge, stopping the medication under medical supervision protects the patient's long-term well-being.  

Addressing Misuse and the Complex Role of Cannabis 

Because stimulant medications target brain reward and wakefulness circuitry, they can foster a propensity for misuse. Studies indicate that more than 1 in 5 adults prescribed stimulants have misused them, and 1 in 6 have diverted their medication to others. The task force emphasizes that deprescribing is warranted if a patient persistently takes doses higher than prescribed against medical advice, uses the medication purely for unauthorized performance enhancement, or has an untreated, coexisting substance use disorder.  

And what about cannabis? This topic sparked the most debate among the experts, falling just short of an official consensus with 71% agreement that regular cannabis use alone shouldn't automatically trigger a stimulant stoppage. Recognizing the complexity, such as how chronic cannabis use can overlap with ADHD executive function deficits, the task force proposed a structured monitoring approach instead of an immediate cutoff. Clinicians are encouraged to track the patient every 1 to 3 months using standardized symptom tools and random urine drug screens to verify whether cannabis use is actively neutralizing the stimulant's therapeutic benefits.  

The Path Forward: Safe Tapering and Lifestyle Support 

If you and your doctor decide that stopping a stimulant is the right path, it shouldn’t happen overnight. The task force strongly recommends that medications be gradually tapered off at a rate tailored to the individual to minimize potential disruptions and distinguish between transient withdrawal and a true return of ADHD symptoms.  

Crucially, stopping a medication doesn't mean stopping treatment. The experts highlight that the success of any deprescribing plan is significantly enhanced when patients focus on optimizing modifiable lifestyle factors. Prioritizing sleep hygiene, staying physically active, and implementing structured behavioral strategies can support executive functioning and help sustain your cognitive gains even as the medication is reduced or eliminated.  

The Takeaway: 

The decision to continue or stop an ADHD medication is a deeply personal one that requires balancing real-world efficacy, safety, and individual health changes. These new consensus recommendations provide an essential roadmap to help adults navigate their long-term mental health journeys safely and effectively.  

Are you or a loved one currently evaluating your long-term relationship with ADHD medication? Consider scheduling a check-in with your healthcare provider to discuss whether your current treatment plan still perfectly matches your health needs today. 

ADHD and Health: How Sex Differences Impact Physical Health into Adulthood

Girls are diagnosed with ADHD at less than half the rate of boys, but this gap closes significantly by adulthood. ADHD also looks different in females than in males, with distinct patterns in symptoms, development, functional impairment, economic impact, and long-term outcomes. Despite this, sex differences in how ADHD relates to physical health have been poorly studied. 

Prior research has established that both children and adults with ADHD face elevated risk for a range of physical health conditions. But that work has been hampered by small samples, retrospective designs, and limited population coverage. 

The Study

Denmark's single-payer national health system makes it possible to conduct truly population-wide research. This study drew on Danish national registers to follow more than 825,000 individuals, born between 1984 and 1995, from birth through adolescence and into young adulthood, tracking them across 13 categories of physical disease. Only individuals free of a relevant physical diagnosis at birth were included, and ADHD diagnosis was treated as something that could be acquired over time rather than a fixed characteristic. 

The Results: 

Across both sexes, people diagnosed with ADHD consistently showed higher disease risk than the general population, with cancer being the one notable exception. The absence of a meaningful cancer signal is expected, given that cancer predominantly affects older age groups than those captured in this study. 

For most other disease categories (including infectious, endocrine, metabolic, respiratory, digestive, musculoskeletal, and genitourinary diseases), elevated risk emerged in early adolescence. For the remaining categories, elevated risk was present at all ages studied. 

The magnitude of these risks was often substantial: 

  • Infectious diseases: Males aged 14–23 with ADHD faced about 20% greater risk than peers without ADHD; females in the same age group faced roughly 80% greater risk. These differences converged to around 45% above baseline beyond that age. 
  • Eye diseases: Before age 11, males with ADHD had more than twice the risk of their non-ADHD peers; females had more than five times the risk. By age 22, both sexes converged at roughly 35% above baseline. 
  • Ear diseases: Risk was more than five times higher in children with ADHD under age 7. 
  • Nervous system diseases: Risk more than doubled across all ages studied. 
  • Endocrine, nutritional, and metabolic diseases: Risk more than doubled between ages 7 and 23. 
  • Skin conditions: Risk more than doubled through age 11. 

By early adulthood, individuals with ADHD showed at least 20% greater risk across every disease category except cancer, regardless of sex. 

Sex Differences Shift With Age 

One of the study's more nuanced findings concerns how sex interacts with ADHD diagnosis over time. In the general population, females tend to have higher physical disease risk from the teenage years onward, while males show higher risk in early childhood. ADHD diagnosis disrupted these patterns unevenly, amplifying risk in some groups and age windows more than others. 

Perhaps most notably, the transition into young adulthood appeared to reduce the ADHD-associated gap between the sexes for endocrine, nutritional, and metabolic diseases (from a ninefold female-to-male disparity down to roughly 4.5-fold). The authors suggest this may reflect ADHD's influence on sex hormone activity during this developmental period. 

Takeaway 

This large, population-representative study confirms that an ADHD diagnosis is associated with meaningfully elevated risk across nearly all categories of physical disease, and that this relationship is neither uniform across sexes nor static across the lifespan. The findings underscore the need for sex-sensitive, developmentally informed approaches to the physical healthcare of people with ADHD. 

Antidepressants in Pregnancy and ADHD Risk: What a Major New Analysis Found

Antidepressants are the primary drug treatment for depressive disorders, which affect 15–20% of pregnant women. They are among the most widely prescribed medications worldwide, and their use has increased in recent decades. Understanding their reproductive safety is critical to support informed, evidence-based prescribing during pregnancy. 

A new meta-analysis sheds important light on one of the most debated concerns: whether children born to mothers who took antidepressants during pregnancy face a higher risk of ADHD. 

The Study: 

Pooling 14 studies covering more than 14 million participants, the analysis found that prenatal antidepressant exposure was associated with a 35% higher rate of ADHD in offspring compared to no exposure. A separate look at SSRIs (the most widely prescribed class of antidepressants, including Prozac and Zoloft) across 11 studies and over four million pregnancies found an even higher apparent risk (44%)  after correcting for publication bias. On the surface, these are striking numbers. 

Both associations came with an important caveat: enormous variation between individual studies, a statistical red flag suggesting the results may not reflect a true underlying effect. More tellingly, the apparent risk evaporated entirely when researchers applied a more rigorous method — comparing siblings within the same family, where one child was exposed to antidepressants in the womb, and another was not. 

This sibling-comparison design is particularly powerful because it automatically controls for factors that run in families: shared genes, household environment, parenting, and socioeconomic conditions. When those influences are held constant, the link between antidepressant exposure and ADHD disappears. The same pattern held for SSRIs specifically. 

Two other antidepressant classes, SNRIs (serotonin norepinephrine reuptake inhibitors) and tricyclics, showed no significant association in any analysis. 

“Confounding by Indication”: 

The probable driver of the initial association is what researchers call confounding by indication. The very condition being treated (depression) is itself a risk factor for ADHD in offspring, independently of any medication. Mothers with more severe depression are also more likely to be prescribed antidepressants, meaning the drug and the underlying illness are difficult to disentangle in standard analyses. Sibling studies cut through this problem cleanly. 

The Take-Away: 

The authors concluded that the association between antidepressants and ADHD risk was non-significant across all analyses designed to account for these confounding factors. This doesn’t mean antidepressants are without any reproductive considerations, but it does suggest that ADHD risk, at least, is driven by heritable and family-level factors rather than medication exposure itself. 

For clinicians and patients weighing the risks of treating or not treating depression during pregnancy, this distinction matters considerably.