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Attention Deficit Hyperactivity Disorder (ADHD) is a common condition affecting children and adolescents worldwide, characterized by symptoms such as hyperactivity, impulsivity, and inattention. While traditional treatments like medication and behavioral therapy are often used, some individuals are turning to complementary and alternative therapies (CAM) for help. One such option gaining attention is acupuncture. But does it really work for ADHD?

A recent comprehensive study aimed to evaluate the effectiveness of acupuncture in treating ADHD symptoms. Here’s a breakdown of the findings, with a focus on the age groups included in the research and what these findings could mean for ADHD treatment options.

What the Study Explored

The study in question conducted a systematic review and meta-analysis (SR/MA) of acupuncture trials for ADHD, comparing its effects to traditional treatments such as pharmacotherapy and behavioral therapy. The researchers focused on acupuncture’s impact on core ADHD symptoms like hyperactivity, impulsivity, inattention, and conduct problems, while also exploring how acupuncture might help with other issues, such as learning difficulties and psychosomatic symptoms.

One key feature of this study was the inclusion of a broad age range of participants, specifically children and adolescents. These two groups are the most commonly diagnosed with ADHD, and their responses to treatments can vary significantly. Understanding how acupuncture works for these age groups is critical for evaluating its effectiveness as an ADHD treatment.

Here’s what the study found across the different age groups:

• Children: Acupuncture appeared to be particularly effective in reducing hyperactivity and impulsivity in younger children with ADHD. These symptoms, often more prominent in younger populations, responded well to acupuncture when used alongside other treatments like medication.
  
  
• Adolescents: For adolescents, acupuncture seemed to improve both hyperactivity and inattention, two symptoms that can often become more challenging as children grow older. This age group also benefited from acupuncture’s ability to reduce side effects from ADHD medications, such as irritability or sleep disturbances.
  
  
• Combined Effects for Both Groups: When acupuncture was used in combination with pharmacotherapy, it also helped reduce side effects such as sleep problems and appetite loss in both children and adolescents. This could make it an attractive adjunctive treatment for those already on medication but experiencing undesirable effects.
  
  
• Inattention and Conduct Problems: For both children and adolescents, acupuncture used in conjunction with either medication or behavioral therapy showed notable improvements in inattention and conduct problems—two of the most difficult symptoms of ADHD to manage.
  
  
• Learning Difficulties and Psychosomatic Symptoms: Interestingly, the combination of acupuncture and medication provided significant improvements in learning difficulties, which are particularly relevant for children with ADHD. Meanwhile, acupuncture paired with behavioral therapy had a positive impact on psychosomatic symptoms, such as anxiety or stress, that often co-occur with ADHD.
  
  

Despite these promising results, the study also highlighted several limitations:

• Study Quality Issues: The quality of the studies reviewed was often low, with many trials lacking the rigorous controls needed for high confidence in their results. For example, only a small number of trials used objective ADHD diagnostic tools, which could lead to biases in assessing acupuncture’s effectiveness.
  
  
• Need for More Research: There is a lack of large-scale, high-quality randomized controlled trials (RCTs) comparing acupuncture with placebo treatments, which makes it hard to determine whether acupuncture’s effects are truly therapeutic or simply a placebo.

Conclusion: Is Acupuncture a Good Option for ADHD?

In short, and as is so often the way of evidence-based medicine, we still can’t say with absolute certainty one way or the other. These studies may show promise in improving hyperactivity, impulsivity, inattention, and conduct problems– in both children and adolescents. However, the evidence is not yet strong enough to recommend it as a primary treatment. While it may serve as a helpful complement to standard therapies, especially for those struggling with medication side effects or access to behavioral therapy, more research is needed to establish its effectiveness.

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This New York Times article, “5 Takeaways from New Research about ADHD”, earns a poor grade for accuracy. Let’s break down their (often misleading and frequently inaccurate) claims about ADHD. 

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The Claim: A.D.H.D. is hard to define/ No ADHD Biomarkers exist

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The Reality: The claim that ADHD is hard to define “because scientists haven’t found a single biological marker” is misleading at best. While it is true that no biomarker exists, decades of rigorous research using structured clinical interviews and standardized rating scales show that ADHD is reliably diagnosed. Decades of validation research consistently show that ADHD is indeed a biologically-based disorder. One does not need a biomarker to draw that conclusion and recent research about ADHD has not changed that conclusion. 

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Additionally, research has in fact confirmed that genetics do play a role in the development of ADHD and several genes associated with ADHD have been identified.  

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The Claim: The efficacy of medication wanes over time

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The Reality: The article’s statement that medications like Adderall or Ritalin only provide short-term benefits that fade over time is wrong. It relies almost entirely on one study—the Multimodal Treatment Study of ADHD (MTA). In the MTA study, the relative advantage of medication over behavioral treatments diminished after 36 months. This was largely because many patients who had not initially been given medication stopped taking it and many who had only been treated with behavior therapy suddenly began taking medication. The MTA shows that patients frequently switched treatments. It does not overturn other data documenting that these medications are highly effective. Moreover, many longitudinal studies clearly demonstrate sustained benefits of ADHD medications in reducing core symptoms, psychiatric comorbidity, substance abuse, and serious negative outcomes, including accidents, and school dropout rates. A study of nearly 150,000 people with ADHD in Sweden concluded “Among individuals diagnosed with ADHD, medication initiation was associated with significantly lower all-cause mortality, particularly for death due to unnatural causes”. The NY Times’ claim that medications lose their beneficial effects over time ignores compelling evidence to the contrary.

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The Claim: Medications don’t help children with ADHD learn 

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The Reality: ADHD medications are proven to reliably improve attention, increase time spent on tasks, and reduce disruptive behavior, all critical factors directly linked to better academic performance.The article’s assertion that ADHD medications improve only classroom behavior and do not actually help students learn also oversimplifies and misunderstands the research evidence. While medication alone might not boost IQ or cognitive ability in a direct sense, extensive research confirms significant objective improvements in academic productivity and educational success—contrary to the claim made in the article that the medication’s effect is merely emotional or perceptual, rather than genuinely educational. 

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For example, a study of students with ADHD who were using medication intermittingly concluded “Individuals with ADHD had higher scores on the higher education entrance tests during periods they were taking ADHD medication vs non-medicated periods. These findings suggest that ADHD medications may help ameliorate educationally relevant outcomes in individuals with ADHD.”

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The Claim: Changing a child’s environment can change his or her symptoms.

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The Reality: The Times article asserts that ADHD symptoms are influenced by environmental fluctuations and thus might not have their roots in neurobiology. We have known for many years that the symptoms of ADHD fluctuate with environmental demands. The interpretation of this given by the NY Times is misleading because it confuses symptom variability with underlying causes. Many disorders with well-established biological origins are sensitive to environmental factors, yet their biology remains undisputed. 

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For example, hypertension is unquestionably a biologically based condition involving genetic and physiological factors. However, it is also well-known that environmental stressors, dietary

habits, and lifestyle factors can significantly worsen or improve hypertension. Similarly, asthma is biologically rooted in inflammation and airway hyper-reactivity, but environmental triggers such as allergens, pollution, or even emotional stress clearly impact symptom severity. Just as these environmental influences on hypertension or asthma do not negate their biological basis, the responsiveness of ADHD symptoms to environmental fluctuations (e.g., improvements in classroom structure, supportive home life) does not imply that ADHD lacks neurobiological roots. Rather, it underscores that ADHD, like many medical conditions, emerges from the interplay between underlying biological vulnerabilities and environmental influences.

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Claim: There is no clear dividing line between those who have A.D.H.D. and those who don’t.

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The Reality: This is absolutely and resoundingly false. The article’s suggestion that ADHD diagnosis is arbitrary because ADHD symptoms exist on a continuum rather than as a clear-cut, binary condition is misleading. Although it is true that ADHD symptoms—like inattention, hyperactivity, and impulsivity—do vary continuously across the population, the existence of this continuum does not make the diagnosis arbitrary or invalidate the disorder’s biological basis. Many well-established medical conditions show the same pattern. For instance, hypertension (high blood pressure) and hypercholesterolemia (high cholesterol) both involve measures that are continuously distributed. Blood pressure and cholesterol levels exist along a continuum, yet clear diagnostic thresholds have been carefully established through decades of clinical research. Their continuous distribution does not lead clinicians to question whether these conditions have biological origins or whether diagnosing an individual with hypertension or hypercholesterolemia is arbitrary. Rather, it underscores that clinical decisions and diagnostic thresholds are established using evidence about what levels lead to meaningful impairment or increased risk of negative health outcomes. Similarly, the diagnosis of ADHD has been meticulously defined and refined over many decades using extensive empirical research, structured clinical interviews, and validated rating scales. The diagnostic criteria developed by experts carefully delineate the point at which symptoms become severe enough to cause significant impairment in an individual’s daily functioning. Far from being arbitrary, these thresholds reflect robust scientific evidence that individuals meeting these criteria face increased risks for the serious impairments in life including accidents, suicide and premature death. 

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The existence of milder forms of ADHD does not undermine the validity of the diagnosis; rather, it emphasizes the clinical reality that people experience varying degrees of symptom severity.

Moreover, acknowledging variability in severity has always been a core principle in medicine. Clinicians routinely adjust treatments to meet individual patient needs. Not everyone diagnosed with hypertension receives identical medication regimens, nor does everyone with elevated cholesterol get prescribed the same intervention. Similarly, people with ADHD receive personalized treatment plans tailored to the severity of their symptoms, their specific impairments, and their individual circumstances. This personalization is not evidence of arbitrariness; it is precisely how evidence-based medicine is practiced. In sum, the continuous nature of ADHD symptoms is fully compatible with a biologically-based diagnosis that has substantial evidence for validity, and acknowledging symptom variability does not render diagnosis arbitrary or diminish its clinical importance.

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In sum, readers seeking a balanced, evidence-based understanding of ADHD deserve clearer, more careful reporting. By overstating diagnostic uncertainty, selectively interpreting research about medication efficacy, and inaccurately portraying the educational benefits of medication, this article presents an overly simplistic, misleading picture of ADHD.

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Recent research suggests that inflammation may play a role in ADHD. Inflammation, marked by elevated proteins and cytokines, affects brain development and structure. Evidence suggests it plays a role in the development of ADHD, making the study of inflammatory markers crucial. 

The platelet-to-lymphocyte ratio (PLR) is a cost-effective test for predicting outcomes of chronic inflammation and neuroimmune diseases. Studies show PLR may be an important inflammatory marker in the pathophysiology of ADHD in children. 

The Study:

A Chinese study team used the National Health and Nutrition Examination Survey (NHANES) database maintained by the National Center for Health Statistics of the United States to investigate the association between PLR and ADHD in children aged 6–14. 

The team identified ADHD through prescriptions of ADHD medications. 

After exclusions for missing information, the study encompassed 1,455 children. 

The authors adjusted for the following potential confounders: sex, age, race, poverty-to-income ratio, maternal age at childbirth, smoking during pregnancy, asthma, health insurance status, dietary inflammatory index, monocyte count, segmented neutrophil count, eosinophil count, and basophil count. 

They also split the PLR results into quartiles, with the first quartile having the lowest readings. 

Prescriptions of ADHD medications were twice as frequent among children in the second quartile as they were among children in the first quartile. They were four times as frequent among children in the third quartile than among children in the first quartile.  

Conclusion: 

The team concluded, “These findings further support the potential role of inflammation in the onset and development of ADHD, providing preliminary evidence for PLR as a potential biomarker for ADHD and suggesting its possible use in identifying high-risk populations. However, considering the limitations of this study, future research should be designed as larger-scale, prospective, multi-center randomized controlled trials to validate these findings and further explore the relationship between inflammatory mechanisms and ADHD.” 

In other words, this study suggests that while high PLR values may serve as a potential biomarker for ADHD, particularly in specific high-risk groups, further research is needed to confirm these findings and fully understand the role of inflammation in ADHD development. Larger, more robust studies will be crucial to validating PLR as a reliable tool for identifying at-risk populations.

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ADHD is the most prevalent neurodevelopmental disorder. Nearly 1% of pregnant women in the Nordic countries and more than 1% in the United States are prescribed ADHD medications, ranking these among the most commonly used medications during pregnancy. However, the safety of exposing a fetus to ADHD medications is still uncertain, prompting many expectant mothers to stop using them out of fear for their unborn child’s well-being. 

The Study:

A European research team conducted a comprehensive nationwide study on the safety of ADHD medications during pregnancy using populations from Sweden and Denmark. The Swedish population was studied first, followed by inclusion of a separate study of the Danish population. Results were then combined through meta-analysis. Nordic countries, with their single-payer national health insurance systems and national population registers, facilitate the tracking of residents’ health from birth to death, thus providing robust data for such studies. 

The team accounted for various potential confounders, including maternal age, year of delivery, whether the mother was a first-time parent, self-reported smoking during pregnancy, and any psychiatric history. They also considered psychiatric inpatient or outpatient treatment received within two years before pregnancy, as well as the dispensing of other psychotropic medications during pregnancy, including antidepressants, antipsychotics, antiseizure medications, and anti-anxiety medications. Additionally, they examined the highest level of maternal education and civil status at delivery (married or cohabiting compared to single, divorced, or widowed). 

Out of 861,650 Swedish children, 2,257 were exposed to ADHD medications during pregnancy. Another 3,917 were born to mothers who discontinued ADHD medications before pregnancy.  

Children exposed to ADHD medications had lower rates of ADHD, autism spectrum disorder, and overall neurodevelopmental disorders; however, none of these differences were significant. 

Limiting the analysis to siblings to control for family environmental influences and genetics likewise found no significant differences.  

A meta-analysis combining the Swedish results with a separately conducted nationwide population study in neighboring Denmark similarly found no significant differences between children exposed to ADHD medications during pregnancy and children born to mothers who discontinued ADHD medications before pregnancy. 

Conclusion:

The team concluded, “Overall, our study provides reassuring evidence that continuing ADHD medication during pregnancy does not increase the risk of long-term NDDs [neurodevelopmental disorders] in offspring." 

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A new large-scale study has shed light on which treatments for attention-deficit/hyperactivity disorder (ADHD) in adults are most effective and best tolerated. 

Researchers analyzed 113 randomized controlled trials involving nearly 15,000 adults diagnosed with ADHD. These studies included medications (like stimulants and atomoxetine), psychological therapies (such as cognitive behavioral therapy), and newer approaches like neurostimulation.

The Findings

Stimulant medications (lisdexamfetamine and methylphenidate) as well as selective norepinephrine reuptake inhibitors (SNRI) (atomoxetine) were the only treatments that consistently reduced core ADHD symptoms—both from the perspective of patients and clinicians. It may be worth noting that atomoxetine, while effective, was less well tolerated, with more people dropping out due to side effects.

Psychological therapies such as CBT, mindfulness, and psychoeducation showed some benefits, but mainly according to clinician ratings—not necessarily from the patients themselves. Neurostimulation techniques like transcranial direct current stimulation also showed some improvements, but only in limited contexts and with small sample sizes.  

Conclusion 

So, what does this mean for people navigating ADHD in adulthood? Stimulant medications remain the most effective treatment for managing ADHD symptoms day-to-day but nonstimulant medication are not far behind, which is good given the problems we’ve had with stimulant shortages. This study also supports structured psychotherapy as a viable treatment option, especially when used in conjunction with medication. 

The study emphasizes the importance of ongoing, long-term research and the need for treatment plans that are tailored to the individual ADHD patient– Managing adult ADHD effectively calls for flexible, patient-centered care.

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Precocious puberty (PP) is defined as the onset of secondary sex characteristics before age 8 in girls or age 9 in boys.  

Because it accelerates skeletal maturation by prematurely shutting down the cartilage growth plate at the tip of long bones, it tends to lead to shorter height in adulthood. It is also known to place an additional psychological burden on children, especially girls. Girls are four to 38 times more likely to develop PP than boys. 

Taiwan has a single-payer national health insurance system, called National Health Insurance, that encompasses 99.6% of the island’s population. The Ministry of Health and Welfare uses it to maintain the National Health Insurance Research Database (NHIRD), enabling researchers to conduct nationwide population studies. 

Using this database, a Taiwanese study team investigated the relationship between ADHD and precocious puberty among children and adolescents (under 18). And because methylphenidate (MPH) is the only psychostimulant approved for the treatment of ADHD in Taiwan, the team also explored the effect of MPH on this relationship. 

Most diagnoses of ADHD in the NHIRD are made by board-certified psychiatrists, enhancing diagnostic validity. 

Of the more than 3.3 million persons born in Taiwan between 1997 and 2001, 186,681 were diagnosed with ADHD. Of these, 122,302 were prescribed MPH. 

After adjusting for sex, low-income households, and neuropsychiatric comorbidities, children diagnosed with ADHD were twice as likely to be diagnosed with PP. This held equally true for boys and girls. 

However, children diagnosed with ADHD and prescribed MPH were more than a third less likely to subsequently be diagnosed with PP than those diagnosed with ADHD but not prescribed MPH.  

For girls with ADHD, who without an MPH prescription were nine times more likely than boys with ADHD to be diagnosed with PP, an MPH prescription reduced that ratio to five times more likely than boys with ADHD and prescribed MPH. 

That suggests a strong protective effect of MPH.  

The team concluded, “Our study found that children with ADHD were at a greater risk of PP, and girls with ADHD were a particularly vulnerable group. … MPH appeared to be protective against PP in patients with ADHD, especially in girls. However, these preliminary results need further validation.” 

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Maternal infections and inflammatory responses during pregnancy have been proposed as risk factors for neurodevelopmental disorders such as ADHD. 

Taiwan has a single-payer health insurance system that covers virtually the entirety of its population. Its Ministry of Health and Welfare maintains the National Health Insurance Research Database (NHIRD), with detailed information on outpatient services, hospitalizations, and medical treatment for nearly 99% of all residents. 

A Taiwanese study team used NHIRD to examine to examine the relationship between maternal hospitalization for infection, and early childhood infection, and subsequent ADHD in offspring. The study cohort originated with all 3,260,879 individuals born between 2001 and 2018. 

The team excluded births from foreign mothers, still births, births with congenital defects, low birth weights, abnormally late births, twins, triplets, and other multiple births, culminating in a final population cohort of 2,885,662 live-born single infants across 1,893,171 families, and 1,864,660 individuals with full siblings from 872,169 families comprising the full sibling cohort. 

Study participants were followed until diagnosis of a neurodevelopmental disorder, their death, or the end of 2021. 

After adjusting for sex, birth year, paternal and maternal ages, birthweight, birth season, parity, delivery method, 1 minute APGAR score (evaluating baby’s appearance, pulse, grimace, activity and respiration at birth), gestational age, pregnancy and delivery complications, parental history of neurodevelopmental disorders, maternal asthma and diabetes, urbanization level of the residential area, and family’s insurance amount, offspring of mothers hospitalized for infections had 14% greater odds of being subsequently diagnosed with ADHD. 

However, in the full sibling cohort of over 1.8 million, this association vanished. That held true for each of the three trimesters of pregnancy. It also held true for bacterial infections. Surprisingly, offspring of mothers hospitalized for viral infections were 24% less likely to be diagnosed with ADHD than their siblings not exposed to maternal viral infection. Because of that, they also had a 6% lower risk overall. 

After the same adjustments, early childhood infection was associated with 16% greater odds of being diagnosed with ADHD. 

Nevertheless, in the full sibling cohort of over 1.8 million, this association again vanished. That held true overall, as well as separately for childhood infections in months 1-6 and months 7-12. The association vanished altogether both for bacterial infections as well as for viral infections. 

The authors concluded, “the results of this nationwide birth cohort study with population and sibling analyses suggest that the association between maternal infection during pregnancy and offspring neurodevelopmental risk is largely due to familial confounding factors.” 

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Most previous studies of suicide and self-harm risk among persons with ADHD have focused on adolescents and adults. They’ve also tended to be cross-sectional, analyzing data from a population at a specific point in time. 

An Australian study team took a different approach, conducting a before-and-after study through the birth cohort of the Longitudinal Study of Australian Children (LSAC), comprising 5,107 children who have been followed up every two years since birth. 

The diagnosis of ADHD was based on parents reporting that their child had received a diagnosis of ADHD at or before age ten.  

Suicide and self-harm were defined as children’s self-report at age 14 of any thought or attempt of suicide and self-harm respectively over the past year. 

The team adjusted for the following confounders: socioeconomic status, birth weight, ADHD medication history, maternal education level, maternal age at birth, experience in bullying victimization at age 12, and depression score based on Short Mood and Feelings Questionnaire (SMFQ). 

Of the 5,107 participants, 3,696 had all the valid data required for analysis and were included in the final cohort. Of these, 3.6% were diagnosed with ADHD by age 10. 

With diagnosis of ADHD at age 10 and all other factors held constant: 

• The odds of suicidal thought, plan, or attempt at age 14 increased elevenfold. This was twice as pronounced among boys as among girls. 

• The odds of self-harm at age 14 increased 25-fold. This was more than three times as pronounced among boys as among girls. 

Both depression and exposure to bullying were statistically significant mediators for the relationship. Nevertheless, depression and exposure to bullying each accounted for well under 10% of the overall effect. 

Neither socioeconomic status nor maternal factors had any significant mediating effect on outcomes. 

Conclusion:

The authors concluded, “This study provides compelling evidence that children diagnosed with ADHD at the age of 10 years face significantly elevated risks of experiencing suicidal thoughts, planning, or attempts, as well as self-harm, by the age of 14 years, which underscores the critical importance of recognizing and addressing these heightened risks in children with ADHD.” 

While factors like depression and bullying contribute, ADHD itself remains a key risk factor. Early intervention and strong mental health support are crucial to protecting these children’s well-being.

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Noting that “Recent research has demonstrated that some gut bacteria can affect the nervous system,” and speculating that “dysregulation in the gut microbiota may increase the incidence of ADHD by overproducing reactive oxygen and nitrogen species, thereby causing neuroinflammation and oxidative stress”, a Taiwanese study team decided to explore whether early-life use of antibiotics – in the first two years – is associated with increased risk of subsequent diagnosis of ADHD. 

Because Taiwan has a single-payer national health insurance system that covers 99.8% of the island’s population, they were able to use the system’s National Health Insurance Research Database (NHIRD) and Maternal and Child Health Database (TMCHD) to include all 1.6 million children born between 2004 and 2012. 

Of these, a little over 1.1 million were given antibiotics before turning two years old, and just over 460,000 were not given antibiotics in the same time frame. 

The mean follow-up period for records of subsequent ADHD diagnoses was seven years. 

The team adjusted for confounding variables: sex, gestational age at birth (weeks), and birth weight (grams) of the children, and age at birth (years), insurance amount (New Taiwan Dollar (TWD)), insurance location, method of delivery, comorbidities, and medication used during pregnancy. 

With these adjustments, early-life antibiotics use was associated with a 12% increase in likelihood of being subsequently diagnosed with ADHD. 

However, looking at the effects of antibiotics as an undifferentiated grouping turned out to be misleading, because the association was limited to only some classes of antibiotics.  

Penicillins were associated with a 22% increase in risk of subsequent ADHD diagnosis, cephalosporins with a 10% increase.  

On the other hand, there was absolutely no such association for tetracyclines, macrolides, and quinolones. 

The Take-Away: 

This study found that children in Taiwan who took certain types of antibiotics before age 2 had a slightly higher risk of developing ADHD later in life.  More work is needed to determine if this finding is due to unmeasured confounding before a causal link can be concluded.

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Background: 

Noting that “the results of previous investigations into the therapeutic benefits of probiotics in the treatment of ADHD symptoms remain inconsistent,” a Taiwanese study team conducted a systematic search of the peer-reviewed medical literature to perform a meta-analysis. 

The Study:

The team identified seven randomized controlled trials (RCTs) that met criteria for inclusion: focusing on children and adolescents under 18, with ADHD diagnoses, comparing probiotic interventions with placebo, and using standardized behavioral rating scales to assess ADHD symptoms. 

Meta-analysis of these seven RCTs with a combined total of 342 participants found no significant improvement in ADHD symptoms. In fact, six of the seven RCTs clustered tightly around zero effect, while the seventh – a small sample (38) outlier – reported a very large effect size improvement.  

Meta-analysis of the three RCTs with a combined 154 individuals that used probiotics with single strains of microorganisms showed absolutely no improvement in ADHD symptoms with no between-study variation (heterogeneity). 

Meta-analysis of the four RCTs with a total of 188 participants that used multiple strains pointed to a medium – but statistically nonsignificant – effect size improvement, with high heterogeneity. Removing the previously mentioned outlier RCT collapsed the effect size to zero. 

Two of the RCTs (with 72 total individuals), including the outlier, offered probiotics in conjunction with methylphenidate treatment. Meta-analysis of the other five RCTs with 270 persons that were structured around pure supplementation yielded absolutely no improvement in ADHD symptoms with no heterogeneity. 

Meta-analyses of the four RCTs with a combined total of 238 participants that examined ADHD subtypes reported no effect on either inattention symptoms or hyperactivity/impulsivity symptoms. 

Trivially, given the lack of efficacy, probiotic regimens were tolerated as well as placebo. 

The Take-Away: 

Ultimately, this meta-analysis found no evidence that probiotics improve ADHD symptoms in children and adolescents. Across seven randomized controlled trials, results consistently showed no significant benefit compared to a placebo. While probiotics were well-tolerated, they did not meaningfully impact inattention, hyperactivity, or impulsivity. These findings suggest that probiotics, whether single or multi-strain, are not an effective treatment for ADHD.

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