Medical Treatments for PCA

Managing Posterior Cortical Atrophy (PCA) requires a highly personalized approach. Because PCA is rare, there have been very few clinical trials focused solely on this condition ^[1]. Instead, doctors often “extrapolate” treatments from what we know about typical Alzheimer’s disease, while also considering newer therapies that target the underlying biology of the disease ^[2][1].

Standard Symptom Management

The goal of standard medications is to manage symptoms and support daily functioning rather than to stop the disease itself.

• Cholinesterase Inhibitors: Medications such as donepezil (Aricept), rivastigmine (Exelon), or galantamine (Razadyne) are commonly used ^[2]. These drugs work by increasing the levels of acetylcholine, a chemical messenger in the brain involved in memory and learning ^[1]. While they were designed for typical Alzheimer’s, some clinicians prescribe them to see if they offer general benefit, although specific evidence for visual improvement in PCA is limited ^[3]. Important side effects to monitor include stomach upset, weight loss, sleep changes, and a potentially dangerous slow heart rate (bradycardia) or fainting.
• Memantine: Often added as the disease progresses, memantine (Namenda) works to modulate a different chemical system (glutamate), and is sometimes considered later, though it requires careful dosing for kidney issues and monitoring for dizziness or confusion ^[2][1].
• Managing Visual Challenges: Because these drugs don’t “fix” the visual processing areas at the back of the brain, they are often paired with non-drug strategies, such as occupational therapy, reading aids, or environmental changes to make your home easier to navigate ^[4][5].

New Disease-Modifying Therapies

You may have heard about new drugs like lecanemab (Leqembi) or donanemab (Kisunla). These are anti-amyloid monoclonal antibodies—treatments designed to clear amyloid plaques from the brain ^[6][7].

It is important to know that PCA patients were not explicitly studied as a separate group in the main clinical trials for these drugs, and any expected benefit would be a modest slowing of clinical decline—not a recovery of lost visual skills ^[8]. However, because PCA is caused by Alzheimer’s pathology in the vast majority of cases, you may be eligible if you meet specific criteria:

• Biological Confirmation: You must have proof of amyloid buildup in the brain, usually through a PET scan or a spinal fluid (CSF) test ^[7].
• Early Symptomatic Stage: These drugs are only approved for people in the “early” stages—either Mild Cognitive Impairment (MCI) or mild dementia ^[6]. Because PCA affects vision first, your doctor will need to determine if your visual-spatial challenges fall within this “mild” window ^[9].
• MRI Safety: Your brain scan must be clear of certain “red flags.” This includes strict, drug-specific limits on the number of microbleeds (tiny spots of old bleeding), larger hemorrhages, or superficial siderosis ^[7][10]. Taking anticoagulants (blood thinners) is also a major safety concern.

Understanding the Risks: ARIA

The biggest safety concern with anti-amyloid drugs is a side effect called ARIA (Amyloid-Related Imaging Abnormalities) ^[6].

• ARIA-E (Edema): Temporary swelling or fluid buildup in the brain ^[6].
• ARIA-H (Hemorrhage): Small spots of bleeding (microbleeds) or iron deposits on the brain’s surface ^[11].

While most cases of ARIA are mild and show no symptoms, some can cause headaches, confusion, or dizziness ^[12]. In rare cases, ARIA can be serious or life-threatening ^[13]. Your risk of ARIA is higher if you carry a specific gene called APOE ε4, so your doctor may discuss genetic testing to refine your risk, which involves privacy and family counseling considerations ^[14][7]. Infusion reactions like chills, fever, and body aches can also occur.

Emergency Warning Signs: Call 911 or emergency services immediately if you experience a sudden, severe headache, new confusion, seizures, sudden weakness, or abrupt changes in balance or vision, as these require immediate assessment.

The Decision-Making Process

Choosing a treatment for PCA is a balance between potential benefits and known risks. Because these new drugs require regular intravenous infusions (usually every two weeks for lecanemab, and every four weeks for donanemab) and strict product-specific MRI schedules, the “burden” of treatment is high ^[7][15].

Currently, there is no evidence yet to prove that these drugs work better or differently in PCA than in typical Alzheimer’s ^[9]. Your medical team will help you weigh whether the possibility of slowing down the disease outweighs the risks of side effects and the intensity of the treatment schedule ^[1].