What Medications Cause Eye Floaters?: Understanding Drug-Induced Visual Disturbances

October 5, 2025 •

4 min read

Approximately 75% of people over the age of 60 experience posterior vitreous detachment (PVD), a common cause of eye floaters, but certain medications can also trigger or accelerate this process. Understanding what medications cause eye floaters is important for recognizing potential drug-related visual side effects and distinguishing them from other ocular issues.

Quick Summary

Certain medications can induce or exacerbate eye floaters by affecting the vitreous gel or leading to other ocular complications. It is crucial to be aware of which drug classes are involved and to promptly report new visual symptoms to a healthcare provider.

Key Points

Fluoroquinolones: Antibiotics like Cipro and Levaquin can disrupt vitreous collagen, increasing the risk of retinal detachment and associated floaters/flashes.
Corticosteroids: Long-term use of systemic steroids like prednisone or intraocular injections can increase eye pressure and accelerate posterior vitreous detachment.
Intravitreal Injections: Injections of medications like Bevacizumab, Ranibizumab, or steroids can physically induce posterior vitreous detachment.
Antihistamines: Drugs like Benadryl can cause dry eyes, which can make existing floaters appear more prominent and noticeable.
Tamoxifen and Cancer Drugs: Certain chemotherapy and hormone therapies, including tamoxifen, are associated with various vision problems and retinal changes.
Sildenafil (Viagra): This medication can cause visual disturbances, including colored vision and floaters, especially at higher doses.
Immediate Evaluation: A sudden increase in floaters or flashes, particularly when accompanied by a shadow or curtain across vision, requires immediate medical evaluation for potential retinal detachment.

The Vitreous and How Medications Interfere

Eye floaters are tiny spots, specks, or strings that drift across your field of vision, caused by microscopic fibers and proteins within the eye's vitreous humor. The vitreous is a clear, gel-like substance that fills the space between the lens and the retina. As a person ages, the vitreous naturally becomes more liquid, and the collagen fibers within it can clump together, casting shadows on the retina that are perceived as floaters.

While age is the most common factor, some medications can accelerate this process or create other conditions that produce floaters. For example, certain drugs can interfere with the structural integrity of the vitreous gel or cause inflammation and bleeding within the eye, introducing debris that appears as floaters.

Fluoroquinolone Antibiotics

Oral fluoroquinolone antibiotics, such as ciprofloxacin (Cipro) and levofloxacin (Levaquin), have been associated with an increased risk of retinal detachment, which often begins with a sudden increase in eye floaters and flashes of light. Research suggests these drugs may interfere with collagen metabolism in connective tissues, potentially affecting the delicate collagen fibers within the vitreous. The risk is highest during current use of the medication.

Corticosteroid Medications

Systemic corticosteroids, like prednisone, and intraocular steroid injections (e.g., dexamethasone, triamcinolone) are linked to several ocular side effects, including increased intraocular pressure and accelerated PVD. In one reported case, a patient developed PVD, which presented as new flashes and floaters, shortly after beginning prednisone. Long-term steroid use is also a known risk factor for cataracts.

Intravitreal Injections

Drugs injected directly into the vitreous to treat retinal diseases can physically induce PVD or cause other visual disturbances. Medications such as bevacizumab (Avastin) and ranibizumab (Lucentis), which are anti-VEGF agents, have been shown to cause PVD after injection. These injections can also cause air bubbles to form, which are seen as shadows until they are absorbed by the eye.

Tamoxifen and Cancer Therapies

The hormone-blocking therapy tamoxifen, used to treat breast cancer, can have various eye-related side effects, including retinal damage, which can lead to visual disturbances like floaters. Additionally, certain chemotherapy drugs and targeted cancer therapies are linked to a range of ocular problems, including blurry vision, dry eyes, and sensitivity to light.

Other Notable Drug Classes

Antidepressants and Antihistamines: Certain older antidepressants (e.g., Elavil) and antihistamines (e.g., Benadryl) can cause visual disturbances or severe dry eyes, which can make pre-existing floaters more noticeable.
Sildenafil (Viagra): This erectile dysfunction medication is known to cause visual side effects, including blue-tinted vision and, in some cases, floaters, especially at higher doses.
Amiodarone: Used for heart rhythm problems, amiodarone can cause deposits to form in the cornea and, more rarely, optic neuropathy, both of which may manifest as visual symptoms.
Anticholinergics: This class of drugs can cause dry eyes and other vision problems that may indirectly make floaters more apparent.
Brimonidine Eye Drops: Used to treat glaucoma, these drops have been listed as potentially causing vitreous floaters.

Comparison of Medications and Their Ocular Side Effects


Drug Class	Example Medications	Ocular Side Effect	Mechanism
Fluoroquinolone Antibiotics	Ciprofloxacin, Levofloxacin	Increased risk of retinal detachment and associated floaters/flashes	Interference with collagen metabolism, potentially affecting vitreous integrity.
Systemic Corticosteroids	Prednisone	Increased intraocular pressure, accelerated PVD, cataracts	Affects fluid balance in the eye and speeds up natural vitreous changes.
Intravitreal Injections	Bevacizumab, Ranibizumab, Triamcinolone	Induction of PVD, air bubbles	Physical disruption of vitreous-retinal adhesion during injection.
Antihistamines	Benadryl	Increased visibility of floaters	Dry eyes caused by the medication can make existing floaters more apparent.
Tamoxifen	Tamoxifen	Retinal toxicity (maculopathy) and visual disturbances	Long-term use can damage the retina, though the exact link to classic floaters can vary.
Phosphodiesterase-5 Inhibitors	Sildenafil (Viagra)	Visual disturbances, colored vision, potential floaters	Mechanism related to inhibition of phosphodiesterase enzymes and blood flow changes.
Heart Medications	Amiodarone	Corneal deposits, optic neuropathy	Accumulation of the drug in eye tissues.

When to Seek Medical Attention

It is crucial to recognize that new or a sudden increase in floaters, especially when accompanied by flashes of light, could be a symptom of a serious condition like a retinal tear or detachment. While many medication-related floaters are benign, a prompt evaluation by an eye care professional is necessary to rule out a medical emergency. Other concerning symptoms include a shadow or curtain moving across your field of vision, which is a classic sign of retinal detachment.

The Importance of a Comprehensive Drug History

When visiting an ophthalmologist or optometrist for visual symptoms, providing a complete and accurate list of all medications you are taking, including over-the-counter drugs and supplements, is essential. This information helps the doctor evaluate if your symptoms could be a side effect of a drug rather than an underlying eye condition. Never stop a prescribed medication without consulting the prescribing doctor, as they can help determine the best course of action.

Conclusion

While eye floaters are often a benign consequence of aging, they can also be an adverse effect of certain medications. From antibiotics that affect connective tissue to steroids that alter vitreous composition and even common antihistamines that cause eye dryness, the pharmacological causes are diverse. Prompt evaluation of new or suddenly worsening visual disturbances, especially those accompanied by flashes, is critical to differentiate a harmless side effect from a serious medical emergency like retinal detachment. Maintaining open communication with your healthcare providers about your medications and any visual changes you experience is the best strategy for protecting your vision.

Learn more about potential drug side effects on the American Academy of Ophthalmology website.

Frequently Asked Questions

Yes, certain eye drops, particularly those containing brimonidine, have been listed as potentially causing vitreous floaters. Additionally, drugs injected directly into the eye can induce posterior vitreous detachment and cause bubbles that look like floaters.

The duration depends on the cause. If related to PVD or other vitreous changes, they may be permanent, though your brain can learn to ignore them. For conditions like drug-induced dry eyes, the floaters may become less noticeable once the medication is stopped and the dryness resolves.

Stopping a medication that causes eye dryness can reduce the prominence of floaters. However, if the medication caused a permanent change like PVD or retinal damage, the floaters may persist. You should always consult your prescribing doctor before stopping a medication.

Floaters from medication are often permanent because the drug may have caused physical changes to the vitreous gel or retina. However, they may become less bothersome over time as your brain adapts. Progressive vision loss from retinal damage can be permanent.

You should contact your ophthalmologist or the prescribing doctor. It's crucial to rule out serious conditions like retinal detachment. Your doctor can evaluate your symptoms and determine if an adjustment to your medication is necessary.

The risk varies significantly depending on the medication. For many drugs, the risk is quite low. However, for certain medications, like fluoroquinolones, the increased risk of floaters and retinal detachment is well-documented, though the overall chance for an individual patient remains small.

No. Many medications can cause vision problems like blurry vision, dry eyes, or sensitivity to light without causing floaters. For example, some drugs can cause corneal deposits or affect the optic nerve, leading to vision changes that do not involve floaters.