
Frequently Asked Questions
Memantine (Namenda)
Memantine (brand name Namenda) is a prescription medicine that affects a brain signaling system linked to glutamate (a major “excitatory” brain chemical). It is not a cure for autism and it does not replace therapy, school supports, or skill-building services. The goal is a time-limited, closely monitored trial to see whether memantine helps with specific, day-to-day problems like sensory overload, big emotional reactions, slow “cool down” after stress, and social withdrawal that worsens when a child is overwhelmed.
Research suggests that memantine may help some youths with autism—especially a subgroup identified in research using specialized brain testing (not available in routine care). In that subgroup, the study showed about 80% improved on memantine vs 20% on placebo. This does not mean everyone will respond, and careful screening and tracking are required.
No. Memantine is FDA-approved for Alzheimer’s disease in adults, and its use for autism is off-
label.
At FHW, only Dr. Hjellen prescribes memantine under this autism protocol. To pursue this
option, you will need to request an appointment with Dr. Hjellen.
When it helps, families most often report things like:
Improved social engagement – most common
Fewer or less intense meltdowns and faster recovery after distress
Better tolerance for noise, touch, transitions, or busy environments
Better ability to pause before reacting
Memantine is not expected to:
“Remove” autism or change identity
Replace speech therapy/OT/behavior therapy/school supports
Automatically improve every area of functioning (benefits—if present—tend to be specific and gradual)
Before starting, FHW requires a comprehensive diagnostic assessment to confirm autism, check for co-occurring conditions, and document a clear baseline. FHW also uses a parent checklist called the GPS-A (Glutamatergic Profile Screener for Autism) to estimate whether a child’s pattern matches the subgroup most likely to benefit. The GPS-A is research-informed and under clinical evaluation (not a diagnostic test).
No. You can self-refer and request an appointment directly. If you prefer, your child’s primary
care clinician or another provider can also send a referral.
This protocol requires frequent in-person monitoring, especially early on:
Baseline visit
Higher frequency during titration
Lower frequency during maintenance
Families should expect at least 16 appointments over a 12-month course if accepted into the
protocol.
FHW tracks change using structured measures, including:
GPS-A (pattern tracking over time)
SRS-2 (social responsiveness)
CGI-I (clinician rating of improvement)
The GPS-A (Glutamatergic Profile Screener for Autism) is a parent-completed questionnaire used in the FHW memantine protocol to help estimate whether a child’s symptom pattern looks like the subtype of autism that may be more likely to respond to memantine. It asks about real-world patterns such as sensory overload, physiologic over-arousal, intensity of reactions, recovery time after stress, and related regulation features. It is not a diagnostic test and it does not “prove” that memantine will work; it is a structured way to guide clinical decision-making when the university grade brain scanning equipment used in research is not available in routine clinical care. The GPS-A is also used as a tracking tool over time so changes can be compared against the child’s baseline profile during the trial.
The research that best identifies which autism patients are most likely to respond to memantine used a specialized type of brain imaging to measure glutamate. That imaging is not available as a routine clinical test for most families in Alaska. FHW developed the GPS-A to bridge that gap by using a structured parent questionnaire that captures the real-world symptom pattern (phenotype) that typically matches the subgroup described in research.
Asking families to travel out of state for advanced imaging is not realistic for most patients, and a commercial screening tool could take many years to reach the clinic due to research validation, publication timelines, and industry/regulatory hurdles. Instead, FHW reviewed the available research on memantine in autism and on the related phenotype and created a screening tool now, with transparency that it has unknown false-positive and false-negative rates. The tradeoff is intentional: we accept some uncertainty in screening so that patients can access a potentially meaningful treatment sooner, within a structured, closely monitored, measurement-based trial.
The GPS-A was created as an evidence-informed replacement for the research-only brain imaging (¹H-MRS glutamate measures) that identified likely memantine responders as this type of brain scan is not clinically available in Alaska.
In practical terms, this is how the GPS-A was created:
Step 1: Start with the research phenotype. Dr. Hjellen reviewed and integrated a wide range of peer-reviewed neuroimaging, neurochemical, and clinical treatment studies linking elevated glutamate with a recognizable pattern of over-arousal, sensory hyperreactivity, and regulation difficulty. This research review was extensive and iterative—requiring cross-comparison across study designs, careful reconciliation of inconsistent findings, review of memantine in general, all available research on memantine’s use in pediatric autism cases, and repeated refinement as the evidence base evolved—rather than relying on any single paper or summary.
Step 3: Add clinic-pattern reality checks. He then converted the research-described profile into parent-observable items across the symptoms most consistently linked to the “high-glutamate” subgroup (sensory reactivity, physiologic arousal/recovery, cognitive/behavioral reactivity, medication/stimulation sensitivity, and stress-linked social withdrawal).
Step 3: Add clinic-pattern reality checks. Item selection and wording were also informed by patterns repeatedly observed in clinical practice, especially in children who appeared to respond to interventions that reduce excitatory “overdrive.”
Step 4: Attempt to reduce false positives. Dr. Hjellen cross-checked the wording against DSM-5-TR autism criteria so the questions would not just restate common autism symptoms. The items were written to focus on how this specific subtype tends to look (for example, not “irritability” in general, but the irritability pattern that happens with overload and excitatory “overdrive”).
Step 4: Draft a structured, scorable tool. The result is a 20-item parent questionnaire rated on a 0–3 scale, producing subscale scores and a total score (0–60) with interpretation bands (e.g., “Probable/Possible/Unlikely” subtype) and pattern cues for clinical review.
Step 5: Filter it through AI. Dr. Hjellen ran the draft through three AI systems to find flaws, check for unclear or “double-meaning” wording, confirm the questions would capture the intended response, and flag items that might be too broad (to limit false positives) or too narrow (to limit false negatives). AI was also used to improve consistency across items, reduce accidental “leading” wording, and tighten readability for parents.
Step 6: Use it as both screening and tracking. The protocol uses the GPS-A at baseline and repeat intervals to help decide whether a trial is reasonable and to document whether the “excitatory overdrive” profile is decreasing over time.
Step 7: Be clear about limits. The GPS-A is an imperfect tool, it has not been subject to academic scrutiny, and will have false positives and false negatives—but it lets families access a structured trial now rather than waiting years for a better vetted tool to be commercially available.
Dosing is weight-based and increases slowly (about every 2 weeks). Each dose increase requires an appointment.
FHW uses immediate-release tablets (commonly 5 mg and 10 mg). Tablets may be split in some cases; they should not be crushed.
Common (usually mild) side effects include headache, sleep changes, stomach upset,
constipation, dizziness, and irritability.
Although these are not expected, a comprehensive approach should include monitoring for:
Behavioral activation / worsening irritability (more impulsive, more explosive, new aggression)
Increased anxiety or overstimulation
Sleep disruption (especially if worse for more than 3 nights in a row)
Daytime fatigue or “flat” engagement (slowed thinking)
Dizziness or balance changes (unsteady—pause dose and call)
Urinary problems (trouble starting urine, going less often, new accidents)
Seizure-like events – exceptionally rare (staring spells, rhythmic movements, confusion after)
Hold the next dose and call if you see:
A dramatic behavior change
Extreme sleepiness, confusion, or unsteady walking
New urinary retention/difficulty voiding
Any seizure-like event
Sleep disruption lasting more than 3 nights
Yes. Memantine should be used with caution (or avoided) with other medicines that act on the same NMDA system, including amantadine, ketamine, and dextromethorphan (a common cough/cold ingredient).
Also tell the clinic if your child is taking things that can make urine more alkaline (for example sodium bicarbonate/baking soda or certain “urine alkalinizing” medicines), because memantine can build up in the body under alkaline urine conditions.
In the published research, after titration, some patients saw improvements within the first
weeks. For others, it may took up to about 8 weeks to see clear benefit. When we reach that 8-week point, we will re-evaluate the treatment course, repeat the scoring tools, and make a joint decision with you about whether to continue the protocol for the remainder of the year.
Do not double the next dose. If several days are missed, contact the prescriber before restarting.
This is treated as a time-limited trial, not an automatic long-term medication. If there is no clear benefit after a fair trial, or if side effects outweigh benefits, the protocol calls for tapering off (rather than stopping suddenly).
At the end of the first year, we will re-evaluate whether continuing the treatment still makes
sense based on the risk-to-benefit balance for your child. We will also review any new research that has been published since the protocol started to make sure decisions reflect the most current evidence. You can choose to leave the treatment protocol at any time, and you can also return to your previous prescriber whenever you want.
Part of the screening process is to determine if a patient is a good match for the expectations within this protocol as well. We will only accept patients/families into this protocol who can commit to consistent follow-through with scheduling and treatment adherence during this time window. Each visit is required to safely monitor side effects, track progress, and decide whether to continue, adjust, or stop the medication. If you cannot commit to the full appointment schedule (especially during dose increases), we should postpone until your schedule allows for consistent attendance.
Although FHW does provide telehealth services, this memantine protocol requires in-person
appointments during this first year. This is intentional: it keeps the process consistent across participants, allows for direct observation so side effects or clinical changes are less likely to be missed, and allows height and weight to be tracked on the same scale for accuracy. It also allows required forms to be completed in real time during designated visits. In-person care also lets the provider gather additional safety data when needed, including vital signs (heart rate and blood pressure) and brief neurological checks (for example reflexes, balance, and dizziness screening such as walking in a straight line or standing still with eyes closed).
Because this is off-label, insurance coverage should not be expected, and families may have
out-of-pocket medication costs.
Most families taking generic memantine tablets who use a discount program can expect a low monthly cost, often around $15–$25/month, depending on the dose. At the time of this writing, Bernie’s Pharmacy was providing a one month supply of the 10mg tablets for around $15.00. However, these prices are not guaranteed and each family should do their own research on cost prior to pursuing this treatment protocol.
No. At this time, protocol participants must use Bernie’s Pharmacy. This is required for
consistency and safety: we want to reduce problems that can come from different distributors or manufacturers, and we want to avoid pharmacy-level delays that can interrupt a structured titration plan. It also reduces the risk of a prescription being delayed because a pharmacist is unfamiliar with off-label use. Using one pharmacy also helps avoid corporate approval barriers that can occur with large chains or mail-order systems. FHW contacted Bernie’s directly, reviewed the protocol expectations with them, and they confirmed they can reliably support the expected patient volume and the specific workflow needs of this protocol.
Yes. Not being a fit for this protocol does not prevent you from receiving care at FHW. We can
still complete an evaluation and discuss other treatment options and supports that better
match your child’s needs.
FHW will want to take over management of the full treatment plan while your child is in this
protocol. This is necessary so we can track medication changes in real time, avoid conflicting
adjustments, and accurately interpret what is helping versus what is causing problems or
benefits. If another prescriber continues to make changes at the same time, it becomes
unreliable (and less safe) to judge the protocol medication’s true effects.
