Eye Health More Eye Issues & Safety Eye Redness Causes and Treatments Why are my eyes bloodshot and should I be concerned? By Troy Bedinghaus, OD Updated on January 19, 2024 Medically reviewed by Dagny Zhu, MD Print Eye redness occurs when blood vessels near the surface of the eye (for example, red veins in your eyes) become swollen. The most common causes of red and bloodshot eyes are painless, but serious conditions (like a corneal ulcer) can be quite painful. You can develop bloodshot eyes temporarily after drinking alcohol, staring at a computer screen for too long, or forgetting to change your contact lenses. But bloodshot eyes also can be caused by an eye injury or eye infection, which can sometimes lead to a red, bloodshot eye on one side. This article will discuss the most common causes of bloodshot eyes and what you can do about each one. Of course, it is always best to seek the advice of your eye healthcare provider, but there are a few red eye home remedies you can try in the meantime for relief. Illustration by Brianna Gilmartin for Verywell Health 1 Contact Lens Wear Contact lenses can be irritating to the eyes, causing them to turn red. Some common reasons contacts may irritate your eyes include: Poor fitLeaving them in too longTraumatic removalWearing a damaged contact lensPoor hygiene Sometimes contact lens complications can cause corneal abrasion—a scratch on the cornea that can then become infected and result in an infectious corneal ulcer. What To Do If you have bloodshot eyes associated with contact lens wear, see an eye doctor right away. They will check for possible complications and provide the correct treatment. 2 Frequent Use of Eye Drops Do you reach for eye drops when you wake up with bloodshot eyes? Watch out for drops that include ingredients that constrict blood vessels such as tetrahydrozoline HCL. They can become less effective as you build up a tolerance to the drug, and they can cause rebound redness (symptoms that return) when the drop is stopped. What to Do Using over-the-counter, preservative-free lubricating eye drops are usually a safe bet to try before consulting with your eye doctor. They can help you identify the cause of your bloodshot eyes and prescribe a safe and effective treatment. 3 Computer Vision Syndrome Red, dry eyes result from a lack of moisture to the eyes. Your tears work to replenish moisture to the eyes by blinking. Blinking is one of the fastest reflexes of the body. However, people tend to blink about half as much as normal when working on a computer. This is known as "computer vision syndrome" or digital eye strain. What to Do Try to reduce redness by blinking more often. You can also replenish moisture in the eye by using artificial tears. 4 Lack of Sleep If you don't get enough sleep, your eyes may show it. Losing sleep tends to increase blood and fluid around the eyes. This makes them appear puffy and red. Lack of sleep can also lead to dry eyes. Your eyes need rest to clean and renew. Unfortunately, when you don't get enough sleep, your eyes don't get the long rest they need for proper fluid circulation. What to Do Be sure to get a good night's sleep for overall eye health. Most adults younger than age 60 need between seven and nine hours of sleep; it's a little less in people 60 or older. 5 Swimming Many people develop bloodshot eyes after spending some time in a pool. Redness occurs when chlorine used in pools causes the eyes to become irritated. As with other causes of bloodshot eyes, this leads blood vessels near the surface of the eye to become enlarged and dilated. If you're prone to getting bloodshot eyes from swimming, wearing swim goggles in the pool is a good option. What to Do If you have blurry vision and eye pain, make an appointment with an eye doctor as soon as possible to rule out an infection associated with swimming water. 6 Smoking Cigarettes Smoking a cigarette releases several harmful chemicals that can irritate the sensitive tissues of the eyes. It also leads to dry eye irritation, disrupting the tear film layer and leading to symptoms of eye inflammation and bloodshot eyes. What to Do See your healthcare provider to discuss eye health, and consider strategies for smoking cessation. Some studies suggest smoking (and secondhand smoke) can increase dry eye and the risk of other eye diseases, including cataracts (cloudiness in the lens of the eye) and macular degeneration. 7 Alcohol and Cannabis Drinking alcohol can cause some people to develop eye redness, notably in people assigned female at birth. This is because alcohol can cause vasodilation (widening of blood vessels). Alcohol is dehydrating and can cause the eyes to appear red and tired. It's well known that using cannabis causes bloodshot eyes too, whether you smoke the plant or consume it as an edible. Vasodilation and eye redness happen because substances affect the surface of the eye. In the case of cannabis, however, there's also some evidence of a pathway for treatment of glaucoma, a pressure-related eye disorder. What to Do The only way to avoid bloodshot eyes due to alcohol or cannabis is to avoid using the substances. Using OTC eyedrops may temporarily relieve redness, but the redness will likely reappear when you use alcohol or cannabis again. 8 Allergies Red, itchy, watering, swelling eyes are one symptom of food allergies. A.D.A.M. You can have bloodshot eyes due to allergies. In addition, red eyes from allergies often burn and itch. With allergies, the eyes become red because the blood vessels in the front part of the eye dilate and become larger. As a result, fluid accumulates and causes swelling. What to Do You can treat this type of redness with cold compresses, artificial tears, avoidance of triggers, and OTC allergy medications. Treatment can also include eye drops targeted for allergies. Note that systemic allergy medications (those that affect the full body) can dry out the eyes and thereby worsen symptoms. 9 Pregnancy Pregnancy causes large changes to several hormones in the body. These shifts can cause the body to produce fewer tears, so your eyes may feel irritated or gritty. In addition, they may appear red and sensitive to light. What to Do If you find it challenging to wear contacts during pregnancy, you may opt for glasses until after you give birth. 10 Photokeratitis Photokeratitis is a painful condition that occurs when your eyes are exposed to ultraviolet (UV) rays. Think of photokeratitis as a sunburn that affects the corneas of your eyes. Ultraviolet rays naturally come from the sun and are also artificially produced in tanning beds. You can get photokeratitis by spending time in the sun or in a tanning bed without sun protection. It can also happen when UV rays reflect off of snow or ice and into your eyes. In addition to redness, symptoms of photokeratitis include watery eyes, blurry vision, and light sensitivity. Symptoms typically resolve within six to 48 hours, though they may be more severe if you are exposed to UV rays for a prolonged period of time. Keep in mind that long-term UV exposure can also lead to increased risk of cataracts, and eye conditions including pterygium (a growth in the corner of the eyes) and pinguecula (a type of eye lesion). What to Do It's imperative that you stay away from further UV ray exposure, so avoid the sun, tanning beds, or other sources as your eye heals. Remove contact lenses if you wear them and avoid touching your eyes. Don't patch the eye. You can use artificial tears or take an OTC pain reliever like ibuprofen to ease your symptoms, but if they don't improve within 72 hours, see your healthcare provider. 11 Pink Eye Bloodshot eyes can be caused by pink eye, also known as conjunctivitis. Pink eye is a swelling or infection of the clear, protective layer that covers the front part of the eye. Pink eye can be caused by allergies, bacteria, viruses, or toxic substances. It is common but usually not serious, with one small study finding that 46% of cases were caused by conjunctivitis (another 32% were due to dry eye). Pink eye is extremely contagious and can be easily transferred by touching your eyes. Avoid sharing towels or physical contact with others. What To Do Visit your healthcare provider if you suspect your bloodshot eyes are due to pink eye. This is especially important if it is associated with pain and vision changes. 12 Blepharitis Find out how you can tell the difference between blepharitis and a stye. rob_lan/Getty Images Blepharitis is a common reason for painful, bloodshot eyes. It is caused by impacted oil glands that can't release the oily layer of the tear film well. This leads to inflammation of the eyelid. Common causes include: Poor makeup hygiene Decreased blinking Ocular demodicosis (a skin mite that normally lives on human skin) Blepharitis is not infectious and usually does not cause permanent damage to your eyesight. Blepharitis symptoms include: A sandy or burning sensation in your eyesExcessive tearingItchingRed and swollen eyelidsDry eyesCrusting eyelids You may wake up with red, bloodshot eyes if you have blepharitis. Eyes do not produce tears when someone is sleeping, so you could wake up with dry, red eyes due to a lack of lubricating tears. What to Do Good eyelid hygiene is important. For example, if you have blepharitis, your healthcare provider may instruct you to clean your lids and lashes with eyelid scrubs regularly. If that doesn't help, your healthcare provider may prescribe antibiotics or other medications. 13 Uveitis Uveitis is an inflammation of the eye's uvea, the middle layer of the eyeball. Symptoms of this condition can occur suddenly and get worse very quickly, leading to serious vision threats. It can cause: RednessPainBlurry visionFloatersLight sensitivity Your healthcare provider will most likely prescribe a form of steroids to help reduce swelling. If they can determine the underlying cause for the uveitis, they will treat the cause as well. What to Do Uveitis should be treated quickly. Other complications, such as uveitic glaucoma or retinal and choroidal scarring, may occur if it lingers. 14 COVID and Red Eyes Studies show that eye symptoms occur in about 5% of COVID-19 cases. When eye symptoms do occur, they often appear before other systemic symptoms, such as fever and headaches. The most common eye symptoms associated with COVID-19 include bloodshot eyes, sensitivity to light (photophobia), soreness, and itchiness. Eye symptoms typically resolve around the same time that other symptoms do. What to Do You can use over-the-counter artificial tears to soothe redness and irritation. If your symptoms persist, or if your vision is affected in any way, contact your healthcare provider. 15 Dry Eye Syndrome A common cause of bloodshot eyes is dry eye syndrome. It occurs when there are not enough natural tears to keep the front part of the eye moist. When your eye becomes dry, it also becomes red and irritated. Dry eyes can occur from: Staring at a computer screen for an extended amount of timeLack of quality sleepWearing your contact lenses for too longCertain medicationsHormonal changes Plugged tear glands What to Do If you have bloodshot eyes due to dry eye syndrome, it might be helpful to use eye drops that moisten the eyes. Lubricant, or rewetting, eye drops are sold over the counter and can be used throughout the day. 16 Injury Redness sometimes occurs with an eye injury. Injuring your eye could be as simple as sticking yourself with a mascara wand or accidentally scratching your eye with a sharp fingernail. When you injure your eye, blood vessels inside the eye enlarge and dilate. This brings blood and cells to heal and repair the injury. A red eye from an injury is also a warning sign to tell you something is wrong with your eye. What to Do Visit your healthcare provider to make sure that you did not significantly damage your eye. 17 Corneal Ulcer A corneal ulcer occurs when the eye's cornea becomes infected, leading to a sore on the cornea. When this happens, nearby blood vessels become enlarged and swollen. As cells rush in to help fight the infection, it can cause visible redness. With a corneal ulcer, the nearby blood vessels enlarge to quickly get important inflammatory cells to the site. In addition to bloodshot eyes, symptoms of a corneal ulcer include: PainDischargeWhite spot on the corneaBlurred visionItchingSensitivity to light The cornea is avascular, meaning normally, the cornea does not have any blood vessels in it. Instead, it gets most of its oxygen and nutrients from tears and the air. Medicated drops that are targeted to treat the cause of the underlying infection are often used to treat corneal ulcerations. The drops may be antibacterial, antiviral, or antifungal. Steroids are not commonly started at the beginning of corneal ulcer treatment. However, your healthcare provider may prescribe them to reduce scarring and inflammation once the infection is under control. What to Do Seek treatment right away. Corneal ulcer treatment needs to be aggressive to prevent potential vision loss and blindness. 18 Subconjunctival Hemorrhage A subconjunctival hemorrhage (also known as bleeding in the eye) causes the white part of the eye to become completely red. It occurs when one of the blood vessels bursts underneath the conjunctiva, the transparent, clear tissue that covers the white part of the eye. The blood has no place to go, so it spreads out like ketchup under plastic wrap. Sometimes the blood can gather so much that the eye appears swollen and pouches outward. It usually does not cause permanent harm to the eye and is rarely painful, but one study found subconjunctival hemorrhage was common enough to be the third-leading cause of eye emergency visits. Common causes include: Contact lens use (primary cause in younger people)Eye surgery complicationsConjunctival inflammation or tumorEye traumaHigh blood pressure (typically in older adults)High cholesterolDiabetes What to Do Schedule an appointment with your eye doctor. They will examine your eye and make sure that no other damage is present. They may also measure your eye pressure and look inside your eye. 19 Acute Angle-Closure Glaucoma Sometimes a bloodshot eye can signal a serious condition. For example, one severe eye condition that may cause red eye is acute angle-closure glaucoma. It occurs when the fluid pressure inside the eye rises quickly. This serious type of glaucoma usually causes: Sudden redness in the eyeSevere eye painBlurred vision (usually occurring in only one eye) What to Do Acute angle-closure glaucoma is a serious medical emergency that can lead to permanent vision loss if not treated quickly. Usually a laser is used to make a small hole in the colored part of the eye to drain the fluid and bring the eye pressure back down to normal. 20 Episcleritis Another cause of bloodshot eyes is episcleritis. This is an inflammation of the thin, clear layer of tissue that lies between the conjunctiva and sclera. Episcleritis causes mild eye pain, irritation, and eye redness. Sometimes the eyes become tender to the touch. Scleritis is a deeper inflammation of the outer coat of the eyeball, called the sclera. In this condition, the eye is usually deep red and usually very painful. Often, scleritis is caused by an autoimmune condition (rheumatoid arthritis, for example). Thus, your healthcare provider may order blood work as part of diagnosing your condition. Red eyes due to swimming, drinking alcohol, wearing contact lenses, or another transient cause will go away on their own. However, red eyes can sometimes be due to serious conditions that require medical attention, such as scleritis. What to Do Episcleritis can be treated with artificial tears. In addition, steroids can be used if this condition is causing troublesome symptoms.Scleritis needs immediate medical attention. It often requires oral anti-inflammatories and topical steroid drops. When to See a Healthcare Provider Bloodshot eyes are most commonly due to harmless causes that will resolve on their own, even without treatment. This includes the following: Wearing contact lensesUsing eye drops too frequentlyStaring at a computer screen for long hoursNot getting enough sleepSwimmingSmoking cigarettesUsing alcohol or cannabisBeing pregnantPhotokeratitis It's best to seek medical attention if eye redness or bloodshot eyes are accompanied by certain symptoms, including: Yellow, brown, or green crust in the eyesPain or tendernessLight sensitivityFeverSymptoms lasting more than one weekExposure to pink eye Allergies, pink eye, blepharitis, and dry eye syndrome are also common causes of bloodshot eyes. While they are not cause for concern, you may need OTC or prescription medication to ease your symptoms. COVID can cause you to have red eyes, too, but the symptom should resolve as you recover from COVID. If you think you may have one of the following conditions, you should get medical attention as soon as possible to prevent serious complications: UveitisEye injuryCorneal ulcerSubconjunctival hemorrhageAcute angle-closure glaucomaEpiscleritis Seek immediate medical attention if you experience vision changes, floaters in your eyes, light flashes, a foreign body sensation in your eye, signs of infection, eye pain, or any other eye symptoms that concern you. Summary Bloodshot eyes can result from many things. Most often, the things that cause dry, red, irritated eyes are minor and can be treated at home. Over-the-counter artificial tears can help to quickly resolve bloodshot eyes in many cases. Taking an antihistamine for seasonal allergies, placing a cool compress over closed eyes, avoiding irritants such as cigarette smoke, using a dehumidifier, and practicing good hygiene with frequent hand washing and clean linens are all practices that help relieve red eyes. However, other causes of red eyes can be more serious and threaten your vision and overall health. So, it's always best to consult your healthcare provider for an accurate diagnosis. 26 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. MedlinePlus. Eye redness. Mclaurin E, Cavet ME, Gomes PJ, Ciolino JB. Brimonidine ophthalmic solution 0.025% for reduction of ocular redness: A randomized clinical trial. Optom Vis Sci. 2018;95(3):264-271. doi:10.1097/OPX.0000000000001182 Lema AK, Anbesu EW. Computer vision syndrome and its determinants: A systematic review and meta-analysis. SAGE Open Med. 2022 Dec 9;10:20503121221142402. doi:10.1177/20503121221142402. McMonnies CW. The clinical and experimental significance of blinking behavior. J Optom. 2020 Apr-Jun;13(2):74-80. doi:10.1016/j.optom.2019.09.002. National Institute of Neurological Disorders and Stroke. Brain basics: Understanding sleep. American Academy of Ophthalmology. What you should know about swimming and your eyes. Bhutia P, Sen S, Nath T, Shamshad MA. The effect of smoking on ocular surface and tear film based on clinical examination and optical coherence tomography. Indian J Ophthalmol. 2021 Jul;69(7):1693-1696. doi:10.4103/ijo.IJO_2840_20. Food and Drug Administration. How Smoking Can Contribute to Vision Loss and Blindness. Magno MS, Daniel T, Morthen MK, Snieder H, Jansonius N, Utheim TP, et al. The relationship between alcohol consumption and dry eye. Ocul Surf. 2021 Jul;21:87-95. doi:10.1016/j.jtos.2021.05.005. Cairns E, Baldridge W, Kelly M. The endocannabinoid system as a therapeutic target in glaucoma. Neural Plasticity. 2016 Jan;2016(1):1-10. doi:10.1155/2016/9364091 Rathi VM, Murthy SI. Allergic conjunctivitis. Community Eye Health. 2017;30(99):S7-S10. Yenerel NM, Küçümen RB. Pregnancy and the Eye. Turk J Ophthalmol. 2015;45(5):213-219. doi:10.4274/tjo.43815 Izadi M, Jonaidi-Jafari N, Pourazizi M, Alemzadeh-Ansari MH, Hoseinpourfard MJ. Photokeratitis induced by ultraviolet radiation in travelers: A major health problem. J Postgrad Med. 2018 Mar;64(1):40-46. doi:10.4103/jpgm.JPGM_52_17 American Academy of Ophthalmology. Photokeratitis. Awad RA, Sesma G, Neyaz SY, Ahmad K, Al Hemaidi SS, Awad AH. Virtual Consultation for Red Eye: Accuracy Assessment in a Primary Care Center. Middle East Afr J Ophthalmol. 2021 Dec 31;28(3):180-183. doi:10.4103/meajo.meajo_306_21. Putnam CM. Diagnosis and management of blepharitis: an optometrist's perspective. Clin Optom (Auckl). 2016;8:71-78. doi:10.2147/OPTO.S84795 American Academy of Ophthalmology. Why are my eyes bloodshot when I wake up? Gamalero L, Simonini G, Ferrara G, Polizzi S, Giani T, Cimaz R. Evidence-Based Treatment for Uveitis. Isr Med Assoc J. 2019 Jul;21(7):475-479. PMID: 31507124. La Distia Nora R, Putera I, Khalisha DF, et al. Are eyes the windows to COVID-19? Systematic review and meta-analysis. BMJ Open Opthalmol. 2020 Sep;5(1):1-13. doi:10.1136/bmjophth-2020-000563 Sheppard AL, Wolffsohn JS. Digital eye strain: prevalence, measurement and amelioration. BMJ Open Ophthalmol. 2018;3(1):e000146. doi:10.1136/bmjophth-2018-000146 Turbert D. What is a corneal ulcer (keratitis)? American Academy of Ophthalmology. Chiang PH, Lai JN, Chiang YC, Hu KC, Hsu MY, Wei JC. Association Between Subconjunctival Hemorrhage and Acute Coronary Syndrome: A 14-Year Nationwide Population-Based Cohort Study. Front Cardiovasc Med. 2021 Oct 1;8:728570. doi:10.3389/fcvm.2021.728570. Petsas A, Chapman G, Stewart R. Acute angle closure glaucoma - A potential blind spot in critical care. J Intensive Care Soc. 2017;18(3):244-246. doi:10.1177/1751143717701946 Salama A, Elsheikh A, Alweis R. Is this a worrisome red eye? Episcleritis in the primary care setting. J Community Hosp Intern Med Perspect. 2018;8(1):46-48. doi:10.1080/20009666.2017.1418110 Promelle V, Goeb V, Gueudry J. Rheumatoid arthritis associated episcleritis and scleritis: An update on treatment perspectives. J Clin Med. 2021 May;10(10):2118. doi:10.3390/jcm10102118 American Academy of Ophthalmology. Home remedies for bloodshot eyes. By Troy Bedinghaus, OD Troy L. Bedinghaus, OD, board-certified optometric physician, owns Lakewood Family Eye Care in Florida. He is an active member of the American Optometric Association. See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit