What drugs make you see double? Understanding Medication-Induced Diplopia

According to the American Academy of Ophthalmology, double vision (diplopia) can be a temporary effect of certain drugs like benzodiazepines and anti-seizure medications. Learning what drugs make you see double? is a crucial step in understanding and managing this potentially disruptive side effect of many common medications.

Quick Summary

Double vision can be a side effect of various medications, including anticonvulsants, antidepressants, and sedatives. It often results from neurological effects impacting eye muscle coordination. Discontinuing the causative drug or adjusting dosage typically resolves the issue.

Key Points

• Common Culprits: Medications such as anticonvulsants (Topiramate, Lamotrigine), benzodiazepines (Alprazolam), and certain antidepressants are known to cause double vision.

• Diverse Mechanisms: Diplopia can be caused by CNS depression, disruption of neurological pathways, or effects on eye muscles, depending on the drug class.

• Dosage Matters: For many drugs, the risk of double vision is dose-dependent, meaning it is more likely at higher doses or when starting therapy.

• Recreational Drug Effects: Abusing substances like alcohol and opioids can also cause visual disturbances, including temporary double vision.

• Professional Guidance is Key: Never stop a prescribed medication without consulting your doctor, as they can help determine the cause and safe next steps.

• Resolvability: Most drug-induced visual side effects are temporary and resolve once the medication is stopped or adjusted, but prompt medical evaluation is necessary.

Understanding Drug-Induced Diplopia

Diplopia, the medical term for double vision, occurs when the eyes' visual axes become misaligned, preventing the brain from fusing the two images into a single, cohesive picture. This misalignment, known as strabismus, can be caused or exacerbated by certain medications that interfere with the complex neurological and muscular systems governing eye movement. While many medication-induced visual disturbances are temporary and dose-dependent, some can be a sign of a more serious underlying issue. It is important to understand which drugs can cause this effect and the mechanisms involved to ensure patient safety.

The Mechanisms Behind Medication-Induced Diplopia

Different classes of drugs can induce double vision through various physiological pathways:

• Central Nervous System (CNS) Depression: Depressants like alcohol, opioids, and benzodiazepines slow down the CNS, which can impair the neural signals that coordinate eye movements. The slowed processing can result in eye muscle weakness or incoordination, leading to binocular diplopia that resolves when either eye is covered.
• Neurological Pathway Disruption: Some psychiatric and neurological drugs interfere with neurotransmitters like serotonin, which plays a role in visual processing. This can affect the brain's ability to coordinate the images from both eyes, causing perceptual disturbances and diplopia.
• Impact on Eye Muscles: Certain medications, like fluoroquinolone antibiotics, have been reported to cause tendonitis in the extraocular muscles, which control eye movement. In cosmetic applications, botulinum toxin can cause temporary double vision if it inadvertently migrates to the extraocular muscles.
• Changes in Accommodative Reflex: Some antidepressants with anticholinergic effects, such as tricyclic antidepressants (TCAs), can disrupt the eye's ability to focus, causing blurred and double vision, especially at high doses.

Classes of Medications That Can Cause Diplopia

Several types of medications are associated with inducing double vision as a potential side effect. This list covers some of the most commonly implicated classes:

• Anticonvulsants/Antiepileptic Drugs (AEDs): Used to treat epilepsy, neuropathic pain, and mood disorders, several AEDs carry a risk of diplopia. The visual side effects of AEDs are often dose-dependent, and symptoms may subside with dosage adjustments. Drugs in this category include:
  • Topiramate (Topamax)
  • Lamotrigine (Lamictal)
  • Lacosamide
  • Gabapentin
  • Carbamazepine
• Benzodiazepines: These depressants used for anxiety and sedation can cause diplopia by suppressing the CNS. Examples include alprazolam (Xanax) and lorazepam. Diplopia may also occur during opioid withdrawal, which can be part of a detoxification process often involving benzodiazepines.
• Antidepressants: While diplopia is considered a rarer side effect, it has been reported with higher doses of certain antidepressants. This can happen due to anticholinergic properties or effects on serotonergic pathways.
  • Selective Serotonin Reuptake Inhibitors (SSRIs): Such as citalopram and sertraline.
  • Tricyclic Antidepressants (TCAs): Such as amitriptyline.
• Opioids: Both opioid use and abrupt withdrawal can cause visual disturbances. While using opioids like heroin, some people may experience a divergence of the visual axes, while withdrawal can cause a convergence, or inward crossing of the eyes.
• Erectile Dysfunction Drugs: Medications such as sildenafil (Viagra) and tadalafil (Cialis) are known to cause visual disturbances, including a bluish tinge to vision and, in rare cases, double vision.
• Heart Medications: Amiodarone, used for heart rhythm problems, is known to cause a vortex pattern on the cornea (vortex keratopathy), which can sometimes lead to visual side effects like halos and blurred vision, and potentially diplopia.
• Antibiotics: Some fluoroquinolones, like ciprofloxacin, have been associated with diplopia due to extraocular muscle tendonitis.
• Bisphosphonates: Used for osteoporosis, drugs like alendronate can cause inflammation in the eye that may result in blurred vision or diplopia.
• Antipsychotics: Certain antipsychotics can affect ocular motor control, and some, like chlorpromazine, have been linked to diplopia.

Comparison of Drug-Induced Diplopia Effects

Drug Class	Mechanism	Risk of Diplopia	Typical Resolution	Additional Vision Effects
Anticonvulsants (e.g., Topiramate, Lamotrigine)	Interference with neurotransmitters, often dose-dependent CNS effects	Common to Very Common, varies by drug	Typically resolves with dose reduction or discontinuation	Blurred vision, nystagmus, glaucoma (rare)
Benzodiazepines (e.g., Alprazolam, Lorazepam)	CNS depression leading to impaired eye muscle coordination	Dose-dependent, can occur during intoxication or withdrawal	Often resolves as the drug clears the system	Blurred vision, altered vision
Antidepressants (e.g., SSRIs, TCAs)	Anticholinergic effects or influence on serotonergic pathways	Less common; reported particularly with high doses	Often resolves with dose adjustment or discontinuation	Blurred vision, dry eyes, pupillary changes
Opioids (e.g., Heroin, Fentanyl)	Affects eye muscle alignment due to CNS effects or withdrawal	Rare during active use, more noted during withdrawal	May resolve spontaneously over weeks or months	Pupil constriction (miosis) during use, dilation during withdrawal
ED Drugs (e.g., Sildenafil, Tadalafil)	Effects on blood flow and retinal photoreceptors	Uncommon	Reversible upon discontinuation	Bluish-tinted vision, blurred vision

What to Do If You Experience Drug-Induced Double Vision

Experiencing new-onset double vision after starting a new medication or changing a dose should be addressed promptly by a healthcare provider. Do not stop taking a prescribed medication on your own, as this can have serious health consequences. A doctor can evaluate your symptoms, determine if they are medication-related, and recommend appropriate steps, which may include:

• Dosage Adjustment: For dose-dependent side effects, simply lowering the dosage may resolve the issue.
• Switching Medications: Your doctor may recommend an alternative medication with a different side effect profile.
• Further Evaluation: Because double vision can signal other serious conditions, a comprehensive eye exam or neurological testing may be necessary to rule out other causes.

Conclusion

Drug-induced diplopia is a recognized side effect associated with a variety of common prescription and recreational substances. It can result from interference with the CNS, neurological pathways, or direct effects on the eye muscles. While many cases are temporary and resolve with medication adjustment, persistent or sudden onset double vision should always be evaluated by a healthcare professional. Open communication with your doctor about any visual changes is critical for your eye health and overall well-being. A recent study identified 17 medications that may cause double vision or harm the eyes, underlining the importance of vigilance.

Frequently Asked Questions

Can over-the-counter medications cause double vision?

Yes, some over-the-counter medications can cause vision problems. Certain antihistamines, for example, can cause blurred or double vision, and some NSAIDs have been linked to visual side effects. It is important to read warning labels and discuss all medications with a healthcare provider.

How long does drug-induced double vision typically last?

The duration of drug-induced double vision is often temporary and depends on the specific drug, dosage, and individual response. Symptoms may subside shortly after the medication is discontinued or the dosage is adjusted.

What is the difference between monocular and binocular diplopia?

Monocular diplopia is double vision that occurs in only one eye and persists when the other eye is covered. Binocular diplopia, which is more commonly linked to medication side effects, is double vision that disappears when either eye is closed.

What should I do if I suspect my medication is causing double vision?

If you experience new or worsening double vision, contact your healthcare provider immediately. It is crucial not to stop your medication abruptly, as this can lead to other complications.

Can illicit drug use cause double vision?

Yes, illicit drug use can cause visual disturbances. For instance, stimulants like amphetamines and cocaine can cause dilated pupils and blurred vision, while opioids like heroin can affect eye alignment and vision.

Can medication-induced double vision be a sign of something more serious?

While often a temporary and dose-dependent side effect, double vision can sometimes indicate a more serious condition, such as increased intracranial pressure or a neurological issue. Prompt medical evaluation is necessary to rule out other causes.

Are older adults more susceptible to medication-induced double vision?

Yes, older adults may be at a higher risk of experiencing medication-induced visual side effects, including double vision. Factors such as pre-existing eye conditions, altered metabolism, and polypharmacy (taking multiple medications) can increase susceptibility.