Alzheimer’s drugs improve key cognitive skills in children with autism and low IQ

By Priyanjana Pramanik, MSc.Reviewed by Susha Cheriyedath, M.Sc.Nov 18 2025

New evidence suggests that Alzheimer’s medications may strengthen key cognitive skills in young people with autism and low IQ, offering a promising direction for future clinical trials.

Systematic Review: Effect of Alzheimer’s disease medications on neurocognitive outcomes in children and adolescents with autism spectrum disorder and low IQ: a scoping review. Image Credit: QINQIE99 / Shutterstock

In a recent review published in the journal Translational Psychiatry, researchers synthesized current evidence regarding the use of medications used to treat Alzheimer’s disease AD to improve cognitive outcomes in children with autism and other developmental challenges.

They concluded that a small, methodologically heterogeneous number of studies provides preliminary evidence that AD drugs may improve general cognitive ability, attention, executive functioning, and language. Benefits were particularly marked for younger children.

Autism and intellectual disability increase AD risk

Children and adolescents with autism spectrum disorder ASD who also have intellectual disability ID face substantial developmental challenges and are at higher risk of poorer long-term outcomes than those with ASD alone.

Research also shows that individuals with ASD plus ID have an elevated likelihood of developing AD later in life, raising the possibility of shared biological mechanisms between the two conditions.

AD is characterized by memory loss and broader cognitive decline, and several medications that have received regulatory approval, such as cholinesterase inhibitors and N-methyl-D-aspartate NMDA receptor antagonists, are used to address these deficits.

Current ASD drugs target irritability, not cognition

Importantly, many of the neurotransmitter systems disrupted in AD, including cholinergic and glutamatergic pathways, are also implicated in ASD, particularly among individuals with low intelligence quotient IQ scores. Despite this overlap, current ASD treatments are limited to managing irritability, with no approved medications targeting cognitive difficulties.

Because cognitive impairments in early childhood strongly influence developmental trajectories, and because neuroplasticity is greatest during this period, there is growing interest in whether early pharmacological intervention might improve outcomes.

However, the cognitive effects of AD medications specifically in young people with ASD and co-occurring ID have not been systematically reviewed in recent years. Researchers addressed these gaps using a scoping review.

A Limited Evidence Base

Researchers initially identified 404 records, of which 16 were screened in full, and only 12 met the inclusion criteria.

These studies, published between 2002 and 2024, involved 353 children and adolescents with ASD and low IQ scores, with sample sizes ranging from single cases to 151 participants. Most were conducted in the United States, with additional studies from Canada and Israel.

The designs were mixed: four randomized controlled trials, two open-label extensions, several retrospective observational studies and case series, and one case report. Six studies evaluated cholinesterase inhibitors (donepezil or rivastigmine), and six examined the NMDA receptor antagonist memantine. Of the eight FDA-approved AD medications that met the eligibility criteria for consideration, only three (donepezil, rivastigmine, and memantine) were represented in the available studies.

Dosing and treatment duration varied substantially. Donepezil was typically titrated from 2.5–5 mg/day to 5–10 mg/day, rivastigmine was given at a stable low dose, and memantine doses ranged widely from 2.5–30 mg/day. Treatment periods spanned from under two weeks to more than four years.

Evidence Regarding Effectiveness

Across cholinesterase inhibitor studies, language was the most frequently assessed domain. Three of five studies detected statistically significant gains in receptive or expressive language, often emerging earlier in younger children. For example, donepezil improved receptive vocabulary in children but not adolescents, with benefits persisting after washout.

Expressive language gains were also reported with both donepezil and rivastigmine. Improvements in executive functioning were consistently observed in the two studies that assessed it, including reductions in hyperactivity and better performance on standardized executive tasks. One study showed better complex attention, and only one of two studies reported enhanced general cognitive ability after long-term treatment.

Memantine studies showed similarly encouraging results. Both studies assessing learning and memory demonstrated significant improvements, typically emerging after longer treatment durations.

Language outcomes were positive in three of five studies, including large case series and caregiver-reported improvements over the longer term. Executive function improved in three of four studies, most consistently in measures of hyperactivity and working memory.

Two of three studies evaluating perceptual-motor functioning reported gains in visuospatial skills, and the one study assessing complex attention found improvements after extended treatment.

One of two studies measuring general cognitive ability reported substantial increases in verbal IQ scores, with five memantine-treated children showing gains of 10 points or more compared with none in the placebo group. Overall, all twelve studies demonstrated improvement in at least one neurocognitive domain, although findings varied by domain and study design.

The Way Forward

This scoping review found preliminary, domain-specific evidence that cholinesterase inhibitors and memantine may improve certain neurocognitive skills in children and adolescents with ASD and low IQ. Gains were most evident in language, executive functioning, learning and memory, and in some cases general cognitive ability, particularly among younger children.

The review’s strength lies in its unique focus on cognitive outcomes rather than core ASD symptoms. However, the evidence base is limited by small samples, heterogeneous designs, short or highly variable treatment durations, inconsistent baseline cognitive assessments, and substantial reliance on caregiver reports in some studies. Few studies included standardized safety assessments or robust long-term follow-up.

Well-designed trials, especially involving younger children and standardized cognitive measures, are needed to clarify efficacy, mechanisms, and optimal treatment timing.