Blurred Vision as a Side Effect of Vyvanse (Lisdexamfetamine)
Yes, blurred vision is a recognized adverse effect of Vyvanse (lisdexamfetamine), documented in both FDA labeling and clinical case reports, though it occurs less commonly than other side effects.
Evidence from FDA Drug Labeling
- The FDA-approved product label for lisdexamfetamine explicitly lists blurred vision, difficulties with visual accommodation, and diplopia among postmarketing adverse reactions reported by patients 1.
- These visual disturbances are documented alongside other ocular effects including mydriasis (pupil dilation) in the official prescribing information 1.
Clinical Case Evidence
- A published pediatric case report documented a 9-year-old boy who experienced significant decrease in visual acuity secondary to accommodation disorder after treatment with lisdexamfetamine (Vyvanse), representing an acute adverse effect that resolved after medication adjustment 2.
- This case emphasizes that any change in vision following introduction of psychostimulant medication should be considered a potential adverse effect 2.
- A 32-year-old man developed sudden blurred vision 17 days after beginning lisdexamfetamine, which was ultimately diagnosed as branch retinal artery occlusion (BRAO), likely due to vasospasm induced by the medication 3.
Mechanism and Clinical Context
- Amphetamine-based psychostimulants like lisdexamfetamine can cause accommodation disturbances (difficulty focusing the lens), which manifests as blurred vision, particularly when trying to focus on near objects 2.
- The mechanism involves mydriasis and interference with the ciliary muscle's ability to adjust lens curvature, leading to impaired visual accommodation 4.
- These ocular effects are listed in the product monograph but are rarely reported in the pediatric literature, suggesting they may be underrecognized 2.
Frequency and Severity
- Visual side effects occur less frequently than the most common adverse reactions such as dry mouth (36%), insomnia (20%), and decreased appetite (8%) in adult patients 1.
- In controlled trials, blurred vision and visual accommodation difficulties were reported in the postmarketing phase rather than during initial clinical trials, indicating they are relatively uncommon but clinically significant when they occur 1.
Clinical Recommendations
- Any patient reporting new or worsening blurred vision after starting Vyvanse should be evaluated promptly, as this may represent accommodation disorder, mydriasis, or in rare cases, more serious vascular events 2, 3.
- If blurred vision is bothersome or interferes with daily activities, consider dose reduction, switching to a different stimulant class (methylphenidate-based), or transitioning to a non-stimulant ADHD medication such as atomoxetine 2.
- Patients should be counseled that visual disturbances may be transient and resolve with continued use or dose adjustment, but persistent symptoms warrant ophthalmologic evaluation 4.