What Medications Require an AIMS Assessment?

Any medication that blocks dopamine receptors in the brain can trigger tardive dyskinesia, and those medications are the ones that call for regular screening with the Abnormal Involuntary Movement Scale. In practice, this means antipsychotic drugs are the primary category, but the list extends to a handful of non-psychiatric medications and, in rare circumstances, other psychotropics. The risk varies widely depending on the specific drug, the dose, and the person taking it, which is exactly why routine AIMS assessments exist.

Why Certain Drugs Trigger Involuntary Movements

Tardive dyskinesia is a delayed movement disorder that shows up as repetitive, involuntary motions, most commonly in the face, jaw, tongue, and lips but sometimes in the limbs and trunk. It develops after prolonged exposure to drugs that block dopamine D2 receptors in the central nervous system. The word “tardive” means late-appearing, and that delay is a defining feature: symptoms typically emerge after months or years of treatment, not days.¹ Clinicians use the AIMS exam specifically to catch these movements early, when they may still be reversible or manageable.

The underlying mechanism is still debated among researchers, but the core connection is straightforward: drugs that chronically block dopamine signaling can cause the brain’s movement-control circuits to become hypersensitive. That hypersensitivity produces the characteristic involuntary movements. Any drug capable of sustained dopamine receptor blockade in the brain is, at least in theory, capable of producing tardive dyskinesia and therefore warrants AIMS monitoring.

First-Generation Antipsychotics

The oldest and most established link is with first-generation (or “typical”) antipsychotics. These drugs, including haloperidol, chlorpromazine, fluphenazine, and perphenazine, were the first antipsychotics developed and tend to bind tightly to dopamine D2 receptors. That strong binding is exactly what makes them effective against psychosis, but it also makes them the highest-risk category for tardive dyskinesia.

A meta-analysis of comparative randomized trials found the annualized incidence of tardive dyskinesia in patients taking first-generation antipsychotics was about 6.5%, compared to roughly 2.6% for those on second-generation agents.² That means in any given year, about one in fifteen people taking a first-generation antipsychotic develops new tardive dyskinesia. Over years of treatment, the cumulative risk climbs considerably.

Research in patients with first-episode psychosis reinforces this. One study of 86 patients found that while overall tardive dyskinesia rates were similar between first- and second-generation drug users in that sample, the severity of movements was significantly higher in the first-generation group.³ So the risk with older antipsychotics isn’t just about whether tardive dyskinesia appears; it’s about how bad it gets. Anyone prescribed a first-generation antipsychotic should be receiving AIMS assessments at regular intervals, full stop.

Second-Generation Antipsychotics

When second-generation (or “atypical”) antipsychotics arrived, there was genuine hope that tardive dyskinesia would become a thing of the past. Drugs like risperidone, olanzapine, quetiapine, aripiprazole, and ziprasidone were designed to have a different receptor-binding profile, and they do carry a lower average risk. But “lower” is not “zero,” and patients on these medications still need AIMS screening.

A systematic review of one-year studies estimated the annual incidence of tardive dyskinesia at about 0.8% in adults taking second-generation antipsychotics, compared to roughly 5.4% in adults taking haloperidol.⁴ That is a meaningful reduction. But the same review found that in older adults, the incidence jumped to over 5% per year even with second-generation drugs, approaching the rates seen with older agents in younger adults. Age, it turns out, matters as much as which drug you take.

More recent post-market surveillance data complicates the picture further. A large analysis found significant variation in tardive dyskinesia risk across individual second-generation antipsychotics, meaning they are not uniformly safer than older drugs. Clozapine stood out as having a lower risk compared to other antipsychotics in the analysis.⁵ The practical takeaway is that switching someone from haloperidol to, say, risperidone does not eliminate the need for AIMS monitoring. It may change how urgently and how often you screen, but the screening itself remains essential.

Non-Psychiatric Medications

The medications most likely to surprise people on this list are the non-psychiatric ones, particularly metoclopramide (sold as Reglan). Metoclopramide is widely used for gastroparesis and nausea, and because it crosses into the brain and blocks dopamine D2 receptors, it carries a risk of tardive dyskinesia.⁶ The FDA added a black box warning to metoclopramide in 2009 for this reason, and treatment guidelines generally advise against using it for more than twelve weeks.

The actual risk, however, appears to be lower than early estimates suggested. One analysis found the rate of tardive dyskinesia from metoclopramide was in the range of 0.1% per 1,000 patient-years, far below the 1% to 10% figures that had been cited in earlier regulatory guidance.⁷ A more recent real-world epidemiology study spanning 2011 to 2020 found the incidence among metoclopramide-treated gastroparesis patients was about 0.37%, and when researchers adjusted for other variables, metoclopramide use itself was not independently associated with increased tardive dyskinesia risk in those patients.⁸

That doesn’t mean metoclopramide is risk-free. The same study identified clear high-risk groups: older adults over 65, women, people with diabetes, those with psychiatric conditions or Parkinson’s disease, and anyone already taking another dopamine-blocking drug.⁸ For patients in these groups who need metoclopramide long term, AIMS assessments are warranted. Prochlorperazine (Compazine), another anti-nausea drug that blocks dopamine receptors, falls into the same category, though it is prescribed less frequently for chronic use.

SSRIs and Other Psychotropics

Antidepressants don’t typically appear on AIMS screening lists, and for good reason: their association with tardive dyskinesia is rare and poorly understood. Still, published case reports exist. A review of 71 cases of movement disorders linked to selective serotonin reuptake inhibitors found that while akathisia and dystonia were the most common reactions, about 11% of reported cases involved tardive dyskinesia-like states.⁹ A separate review cataloging 127 published reports of SSRI-induced movement disorders identified six cases of tardive dyskinesia specifically.¹⁰

These numbers are small enough that routine AIMS screening of all patients on SSRIs would not be practical or warranted. SSRIs are among the most widely prescribed drugs in the world, and the overwhelming majority of patients never develop involuntary movements. But if someone on an SSRI (or SNRI, or another non-antipsychotic psychotropic) begins showing unexplained repetitive movements, clinicians should recognize that the medication is a possible culprit and use the AIMS to document and track the symptoms. Lithium and certain anticonvulsants used as mood stabilizers have also been linked to movement abnormalities in isolated reports, though these associations are even more tenuous.

Who Faces the Highest Risk

Not everyone on a dopamine-blocking drug faces the same odds, and AIMS screening frequency should reflect individual risk. A review of clinical risk factors identified several that increase the chance of developing tardive dyskinesia:¹¹

Older age: The annual incidence of tardive dyskinesia in older adults on second-generation antipsychotics can exceed 5%, matching or approaching rates seen with first-generation drugs in younger patients.⁴
Female sex: Women appear to develop tardive dyskinesia at higher rates than men, and this disparity increases with age.
African and white descent: Certain ethnic backgrounds carry higher risk, though disentangling genetic factors from prescribing-pattern differences is difficult.
Diabetes: Both a metabolic and a modifiable risk factor, diabetes appears consistently in risk models.
Substance use: History of alcohol abuse or dependence has been identified as a significant predictor of orofacial tardive dyskinesia specifically.¹²
Longer illness duration and brain injury: Longer psychiatric illness, intellectual disability, and prior brain damage all raise vulnerability.
Mood disorders: People with mood disorders who are prescribed antipsychotics (often as adjuncts or for off-label indications) may be at higher risk than those with schizophrenia on the same drugs.

For patients with multiple risk factors, more frequent AIMS assessments make sense. A 70-year-old woman with diabetes starting an antipsychotic is in a fundamentally different risk category than a 25-year-old man, and the monitoring schedule should reflect that.

How Often the AIMS Should Be Administered

Clinical guidelines generally recommend AIMS screening every three to twelve months for patients on antipsychotics, with the frequency depending on the person’s risk profile.¹³ A common approach in practice is:

Every 3 months: For patients on first-generation antipsychotics, for older adults, or for anyone with multiple risk factors.
Every 6 months: For most adults on second-generation antipsychotics without additional risk factors.
Every 12 months: For lower-risk patients on second-generation agents, though many clinicians err on the side of more frequent checks.
At baseline: Before starting any antipsychotic, to establish whether any involuntary movements already exist. This baseline is critical because some patients have pre-existing dyskinesias from other causes, and without documentation, it becomes impossible to attribute later movements to the medication.

For non-psychiatric dopamine blockers like metoclopramide, there is less formal consensus, but screening is advisable whenever use extends beyond a few weeks, especially in the higher-risk groups identified earlier. Many gastroenterologists aren’t trained in AIMS administration, which means there can be a gap between the known risk and the actual monitoring that happens in non-psychiatric settings.

What the AIMS Exam Involves

The AIMS itself is a structured, clinician-rated exam that takes about ten minutes. The clinician observes seven body regions: face, lips, jaw, tongue, upper extremities, lower extremities, and trunk. Each region is scored on a five-point severity scale. The exam also includes ratings for overall severity, patient awareness of the movements, and whether the movements cause distress. One of the more distinctive parts of the exam is having the patient open their mouth and stick out their tongue, which often makes subtle tongue movements much more visible.

Importantly, the exam should be conducted when the patient is not overly focused on controlling their movements. Voluntary suppression can mask tardive dyskinesia, so clinicians often observe the patient during casual conversation before asking them to perform specific tasks. Activation maneuvers, like having the patient tap their fingers rapidly, can also bring out involuntary movements that are hidden at rest.

Video-based AIMS assessments have become increasingly accepted, particularly after the expansion of telehealth. Expert consensus from a cross-disciplinary panel confirmed that the structured AIMS exam can be reliably performed over video telehealth with a full-body view, or a modified version covering six of the seven body regions can be done with an upper-body camera.¹⁴ This makes screening more accessible for patients who have difficulty attending in-person appointments, which is especially relevant for people with serious mental illness who may face transportation or mobility barriers.

Distinguishing Tardive Dyskinesia From Other Movement Problems

One reason AIMS assessments are so important is that several drug-induced movement disorders look similar to an untrained eye but require completely different management. A patient who develops stiffness and tremor on an antipsychotic likely has drug-induced parkinsonism, not tardive dyskinesia. Someone with intense restlessness and an inability to sit still may have akathisia. Acute dystonia, which involves sudden, sustained muscle contractions, typically appears within hours or days of starting a drug rather than months later.

Duration of drug exposure is one of the clearest distinguishing features. Acute syndromes like dystonia and akathisia tend to appear early in treatment, while tardive dyskinesia by definition appears after prolonged exposure.¹⁵ The AIMS is specifically designed to capture the involuntary, hyperkinetic (excess movement) pattern of tardive dyskinesia rather than the hypokinetic (reduced movement) pattern of parkinsonism. Using the wrong assessment tool, or no structured tool at all, can lead to misidentification and inappropriate treatment adjustments.

There is also a related phenomenon called withdrawal dyskinesia, which looks like tardive dyskinesia but appears when an antipsychotic is reduced or stopped rather than during ongoing use. Withdrawal dyskinesia typically resolves on its own within six to twelve weeks.¹⁶ Ongoing AIMS assessments during dose changes help clinicians distinguish between a transient withdrawal effect and the emergence of true tardive dyskinesia that may need its own treatment.

When AIMS Scores Lead to Treatment Decisions

An AIMS score by itself doesn’t dictate action; it provides a standardized measure that clinicians track over time. A score that increases consistently over several assessments is a red flag. The question then becomes whether to adjust the antipsychotic dose, switch to a lower-risk agent, or add a medication specifically designed to treat tardive dyskinesia.

Two VMAT2 inhibitors, valbenazine (Ingrezza) and deutetrabenazine (Austedo), are now FDA-approved for treating tardive dyskinesia. In pivotal trials of deutetrabenazine, the highest dose group saw AIMS scores improve by about 3.3 points from baseline over twelve weeks, compared to about 1.4 points in the placebo group.¹⁷ Analysis of what constitutes a meaningful improvement from the patient’s perspective found that a reduction of roughly 2 to 2.5 points on the total motor AIMS score corresponded to a noticeable clinical change. About two-thirds of deutetrabenazine-treated patients achieved at least a 2-point improvement.¹⁸

These numbers highlight why consistent AIMS scoring matters: without a reliable baseline and regular follow-up scores, clinicians can’t tell whether a treatment is actually working or whether apparent improvement is just normal fluctuation. The AIMS turns an otherwise subjective impression into something trackable.

The Gap Between Recommendations and Reality

Despite clear guidelines, AIMS screening rates in clinical practice have historically been dismal. A quality-improvement project at one outpatient psychiatry clinic found that before a targeted intervention, only about 3% of patients on antipsychotics had documented AIMS assessments in their charts. After a structured initiative by residents, that number jumped to 87%.¹⁹ That gap, from 3% to 87% with just a process change, suggests the problem is more about workflow and awareness than clinical disagreement about whether screening should happen.

Several factors contribute to low screening rates. Busy clinic schedules make it easy to deprioritize a ten-minute assessment when there are more pressing concerns. Clinicians outside of psychiatry who prescribe dopamine-blocking drugs, such as primary care physicians managing behavioral symptoms or gastroenterologists prescribing metoclopramide, may not be aware of AIMS or trained to perform it. Electronic health record systems that don’t prompt for AIMS at appropriate intervals also contribute. And there’s a broader issue: for decades, tardive dyskinesia was viewed as something unfortunate but untreatable, which reduced the incentive to screen for it. The availability of VMAT2 inhibitors has changed that calculus. Detecting tardive dyskinesia now leads to a concrete treatment option, giving the AIMS assessment a therapeutic purpose it lacked for most of its history.

Medications Used Off-Label in Non-Psychiatric Settings

Antipsychotics are prescribed far beyond their original psychiatric indications. Quetiapine is widely used for insomnia. Aripiprazole is added to antidepressant regimens for treatment-resistant depression. Olanzapine is sometimes used for chemotherapy-induced nausea. Haloperidol is given in hospital settings for delirium. In each of these situations, the patient is exposed to a dopamine-blocking drug and therefore carries some risk of tardive dyskinesia, yet AIMS monitoring often doesn’t follow the prescription into these non-psychiatric contexts.

The disconnect is particularly concerning for patients who may not realize their medication is an antipsychotic. A person prescribed low-dose quetiapine for sleep by their primary care physician may never be told about tardive dyskinesia risk, let alone scheduled for AIMS assessments. The risk per individual patient on a low-dose second-generation antipsychotic is small, but across millions of off-label prescriptions, the population-level impact adds up. If you are taking any dopamine-blocking medication, regardless of the reason it was prescribed, it is reasonable to ask your prescribing clinician whether AIMS screening applies to you.