Highlights
- Blue vision and other visual side effects from Viagra are rare at lower doses but somewhat more common at higher ones.
- In almost all cases, visual side effects from Viagra are temporary.
- There are several theories as to possible causes of vision side effects, but they haven’t been fully studied.
- If you have risk factors for visual side effects, talk to your doctor before taking Viagra.
Ever taken Viagra and discovered that all of a sudden, you’re seeing the world in shades of blue? If so, you’re not alone — blue vision, also known as cyanopsia, is a potential side effect of Viagra. Users have also been known to experience other visual effects from Viagra, as well. The good news is that these visual side effects are almost always temporary and fade away as the medication clears from your body.
What Are Viagra’s Visual Side Effects?
Generally, when people taking Viagra report vision impacts, they include:
- Cyanopsia, a blue tint to the vision
- Photophobia, a increased sensitivity to light
- Blurred vision
The effects are usually mild to moderate and of short duration. Like many side effects, they will appear naturally and generally fade over time as the body gets used to the medication. But why do these side effects happen in the first place?
Does Viagra Affect Your Vision?
The best place to learn about Viagra side effects is the FDA’s label. The label has a full table of common adverse reactions from Viagra’s clinical trials and how many in clinical trials experienced those effects and at what dosage. We should note that “common” means “experienced by more than 2% of the participants in the trial.”
Abnormal vision is listed as a common side effect, which the FDA defines as “mild to moderate in severity and transient, predominantly color tinge to vision, but also increased sensitivity to light, or blurred vision.” But at low dosages, there doesn’t seem to be much to worry about, as only 1% of the participants experienced any abnormal vision at 25 milligrams, and 2% at 50 milligrams.
However, at 100 milligrams, the percentage goes up to 11%.
Interestingly, though, a second trial found different results. It was a “flexible dose” trial, where dosage was changed according to the data collected during the trial, letting the researchers fine tune the dosage to limit side effects. In that trial, only 3% reported abnormal vision.
In short, the clinical trials found it’s possible to experience vision issues while taking Viagra, but it’s relatively rare except at higher dosages. Further case reports reflected similar results.
Why Does Viagra Cause Blue Vision and Other Visual Side Effects?
There are a few theories as to why Viagra can affect vision, including:
- Enzyme interaction. While Viagra predominantly targets the enzyme phosphodiesterase 5 (PDE5), it can also affect PDE4, which is found in the eye.
- Changes in blood flow. Viagra is a vasodilator, meaning that it works by opening blood vessels to allow better blood flow into the penis. However, this effect isn’t limited to the penis; it affects blood vessels throughout the body, including in the eyes.
- Interaction with other medical conditions. It’s possible that chronic conditions that affect the eyes, like high blood pressure, might interact with Viagra to increase the risk of visual side effects.
These theories have yet to be investigated in large-scale clinical trials, so for now, they’re still theories.
Can I Take Viagra If I Have an Eye Condition?
If you have a condition that affects your vision, you should talk to your doctor before taking Viagra. For most common vision problems, such as astigmatism, you’ll likely be cleared for Viagra use.
There are a few exceptions, however:
- Retinitis pigmentosa
- Any optic nerve abnormality
- Any abnormality of the retina or optic disc (the optic head on the retina where the optic nerve begins)
- Non-arteritic anterior ischemic optic neuropathy (NAION)
If you have any of these conditions, you may be at increased risk of visual problems from Viagra or other prescription erectile dysfunction medications.
What Is Non-Arteritic Anterior Ischemic Optic Neuropathy (NAION) and Does It Interact With Viagra?
Non-arteritic anterior ischemic optic neuropathy is a rare condition where the optic nerve degrades because it’s not receiving enough blood. Although it is rare, it’s the most common form of optic nerve disease, primarily affecting those over the age of 50.
Risk factors for NAION include chronic diseases like diabetes, high blood pressure, and cerebrovascular diseases, but its exact cause is unknown.
It’s not clear that Viagra interacts with NAION based on current studies, in part because people who have these risk factors for NAION are also not good candidates for Viagra. More research would need to be done to draw a definitive conclusion.
If you’re at risk for NAION, check with your doctor before taking Viagra.
What is Retinitis Pigmentosa and Does It Interact With Viagra?
Retinitis pigmentosa (RP) is a hereditary genetic condition where the rod cells of the eye are progressively lost. It’s not clear if there’s any interaction, but men with RP have reported a higher incidence of visual side effects, and a mouse study in 2014 found a potential link.
Current FDA guidance states that “there [is] no controlled clinical data on the safety or efficacy of Viagra in patients with retinitis pigmentosa.”
If you have RP, speak with your doctor about Viagra before seeking a prescription.
Should I Take Viagra If I Have an Optic Nerve Abnormality?
NAION is one of several types of optic nerve abnormality. Others include:
- Optic neuritis. This is the inflammation of the optic nerve that can cause vision problems, pain with eye movement, and even temporary vision loss. Optic neuritis is frequently seen with multiple sclerosis.
- Optic nerve atrophy. This condition involves the gradual degeneration of the optic nerve, leading to vision impairment. It can be caused by various factors, including glaucoma.
- Papilledema. This occurs when there is swelling of the optic nerve head, often due to increased intracranial pressure. It can result from conditions such as intracranial tumors.
- Optic nerve hypoplasia. In this condition, the optic nerve doesn’t develop fully, leading to visual impairment. It can be congenital or acquired.
- Optic nerve glioma. A rare tumor that affects the optic nerve, typically seen in children. It can lead to vision problems.
If you have one of these conditions, speak with your doctor before taking Viagra or any other ED medication.
How Do I Know if Visual Side Effects From Viagra Are Serious?
Some visual side effects could be serious and require immediate medical attention.
These include:
- Sudden vision loss. This is rare but can be a sign of a serious problem that requires immediate medical attention.
- Persistent vision changes. If your visual symptoms don’t resolve after the drug has worn off, that’s a signal to seek medical attention.
- Double vision or severe blurriness. These could be signs of a serious problem that may require immediate treatment.
- Eye pain. Pain in the eyes, sometimes accompanied by vision changes, can be a sign of a severe issue.
If you experience any of these more serious effects, get medical attention right away.
What Should I Do To Limit The Vision Side Effects From Viagra?
There are a few steps you can take if you’re worried about visual side effects from Viagra.
- Get an eye exam before taking Viagra. This is especially important if you’re over 50. Even if you have no history of eye problems, an eye exam will help identify any potential concerns.
- Start with a lower dose. As we noted above, lower doses had much lower incidence of vision effects.
- Check for potential drug interactions. Like any drug, Viagra can interact with other medications in unexpected ways. An easy way to find out if Viagra might interact with a medication you’re currently taking is to check the Drugs.com Drug Interaction Checker. Also, be sure your provider knows about every medication and supplement you’re taking before starting Viagra.
- Buy from a trusted source. Be sure you’re taking authentic, FDA-approved Viagra. Viagra is one of the world’s most popular medications, so it’s a favorite target of counterfeiters. The FDA keeps track of fake pharmacies and tainted supplements as well. Because they’re unregulated, these products can have unexpected side effects.
Buy Your Viagra From eDrugstore, a Source You Can Trust
Viagra has been on the market for nearly three decades and is carefully monitored by authorities around the world, including the FDA. It’s a well-understood medication, and as long as you buy from a trustworthy source, your risk of serious side effects is very low.
At eDrugstore, we’ve been in business since 1998, and we sell only legitimate, FDA-approved medications. Our professional pharmacy and medical staff will answer your questions and help you find the right drug at the right price. We’ll then ship it for free, directly to your door.
To learn more about Viagra and your other ED medication options, visit our erectile dysfunction page.
Dan is a long-time freelance writer focusing on technology, science, health, and medicine, with a lifelong interest in physics, biology, and medicine. His work has taken a particular focus on scientific studies “beyond the headlines,” reading the study to more closely examine the results.