There are no FDA-approved medications specifically for Charles Bonnet syndrome (CBS). Every drug used to manage the visual hallucinations associated with this condition is prescribed off-label, meaning it was originally developed for a different purpose. Several medication classes have shown promise in individual cases and small studies, but the evidence remains limited, and the first step in treatment is almost always improving vision rather than reaching for a prescription.
Why Vision Correction Comes First
Charles Bonnet syndrome occurs when significant vision loss causes the brain to generate its own visual images, producing hallucinations that range from simple geometric patterns to detailed scenes with people, animals, or landscapes. The underlying trigger is the vision loss itself, so the most effective initial approach is optimizing whatever sight remains. Cataract surgery, updated glasses or contact lens prescriptions, and low-vision aids can all reduce the frequency or intensity of hallucinations by giving the brain more real visual input to work with.
When hallucinations persist despite these measures, or when vision can’t be meaningfully improved, medications become the next consideration. Because CBS predominantly affects older adults (the average age in studies is around 80), the choice of medication has to account for the higher risk of side effects in this population.
Antipsychotics
Antipsychotic medications are the most commonly prescribed drugs for CBS, but the evidence supporting their use is surprisingly thin. Most of what clinicians rely on comes from individual case reports rather than controlled trials. Risperidone and olanzapine are the two most frequently mentioned in published cases, with risperidone typically used at low doses.
The challenge with antipsychotics in CBS is twofold. First, their effectiveness for this specific type of hallucination is inconsistent. Some patients respond well, while others see no improvement at all. Second, older adults are particularly vulnerable to antipsychotic side effects, including drowsiness, dizziness, movement problems, and increased fall risk. A case series of eight CBS patients treated with risperidone found them unresponsive to the medication, prompting researchers to explore alternatives.
SSRIs: A Newer Option
When those same eight antipsychotic-resistant patients were switched to escitalopram (a type of antidepressant known as a selective serotonin reuptake inhibitor, or SSRI), the results were striking. Their hallucination severity dropped dramatically over eight weeks, with no reported side effects. This was the first published case series showing SSRIs could effectively treat CBS-related hallucinations, and it’s notable because the patients had already failed antipsychotic therapy.
The average age of these patients was about 82, and the medication was well tolerated at moderate doses. While this is still a small group of patients rather than a large clinical trial, it represents some of the strongest evidence available for any CBS medication. Other SSRIs have also been mentioned in isolated case reports, but escitalopram has the most documented support so far.
Anticonvulsants
Medications originally designed to control seizures have a logical rationale in CBS. The hallucinations are thought to result from abnormal bursts of electrical activity in the visual areas of the brain, similar in some ways to seizure activity. Anticonvulsants work by calming that excessive neuronal firing.
Gabapentin produced complete remission of complex visual hallucinations in one published case at a relatively low daily dose. The proposed mechanism mirrors how the same drug helps with phantom limb pain: the brain is generating sensory experiences from a source that no longer provides real input, and gabapentin dampens that false signal. Pregabalin, a related drug, resolved hallucinations within two days in a patient who had been started on it for nerve pain. Carbamazepine and valproate each have a single successful case report as well.
The advantage of anticonvulsants is that they tend to be better tolerated in older adults than antipsychotics, though they can still cause drowsiness and unsteadiness.
Cholinesterase Inhibitors and Other Approaches
Drugs used to treat Alzheimer’s disease, called cholinesterase inhibitors, have been tried in a handful of CBS cases. The logic is that these medications boost a brain chemical involved in attention and perception, potentially helping the brain better distinguish real visual input from internally generated images. The evidence is limited to case reports.
A few other approaches have appeared in the medical literature, including ondansetron (a nausea medication that affects serotonin receptors) and Yi-Gan San, a traditional Chinese herbal formula with effects on multiple brain chemical systems. None of these have enough evidence to be considered standard treatments.
Why No Standard Treatment Exists
The reason every CBS medication remains off-label is partly practical. CBS is underdiagnosed because many people with the condition don’t report their hallucinations, fearing they’ll be labeled as having a psychiatric illness or dementia. This makes it difficult to recruit enough patients for the large, controlled studies that would be needed to gain regulatory approval for any drug.
The evidence base consists almost entirely of case reports and very small case series. A review in the Journal of Neurology, Neurosurgery & Psychiatry concluded that while case-report evidence exists for anticonvulsants, cholinesterase inhibitors, SSRIs, and atypical antipsychotics, “none can be recommended for routine clinical use without further evidence for their efficacy.”
In practice, this means treatment is highly individualized. A clinician will typically weigh the severity and frequency of the hallucinations against the risks of medication in an older patient, starting with the option that seems safest given that person’s other health conditions and existing medications.
Medication Side Effects to Watch For
Because CBS overwhelmingly affects people over 70, and because older adults are more likely to be taking multiple medications for other conditions, drug interactions and side effects are a real concern. Ironically, some medications commonly prescribed to older adults can themselves trigger visual hallucinations. Blood pressure medications (especially beta-blockers), dopamine-related drugs used for Parkinson’s disease, certain antibiotics, and even some osteoporosis medications have all been linked to visual disturbances.
Before starting a new medication for CBS, it’s worth reviewing whether any existing prescriptions might be contributing to the hallucinations. Removing or adjusting a culprit medication can sometimes resolve the problem without adding another drug to the mix.