Seeing a bright red patch on the white of your eye can be unnerving. In most cases it’s a subconjunctival haemorrhage (also spelt "hemorrhage"): a tiny blood vessel has burst under the conjunctiva, the clear layer over the eye. The blood sits on the surface, not inside the eye, so vision is unaffected. There’s usually no pain, discharge or swelling – at most a mild scratchy feeling. Although it looks dramatic, it’s usually harmless and clears on its own within one to two weeks.
In this guide, we explain what a subconjunctival haemorrhage looks and feels like, common triggers (coughing, straining, minor knocks, blood-thinning medicines), how long it lasts, treatments and what to avoid. You’ll learn when to see a doctor or head to emergency, how it’s diagnosed, key risk factors, and steps to reduce recurrences. We also cover special situations (contact lenses, children and after eye surgery) and how Bright Sight Eye Specialists supports patients in Sydney’s Eastern Suburbs.
What does a subconjunctival haemorrhage look and feel like?
At first glance, a subconjunctival haemorrhage looks like a bright, sharply edged red patch sitting on the white of the eye (the sclera). It lies under the clear surface layer, the conjunctiva, rather than inside the eye, so the coloured part and pupil are untouched and the cornea isn’t coated with blood. It can be a tiny speck or cover a larger area and usually affects one eye. Over a day or two the patch may shift a little or settle towards the lower part of the eye with gravity. As it heals, the colour often changes from vivid red to maroon or brown, then to a yellowish tint, much like a fading bruise.
How it feels is the reassuring part: typically there is no pain, no discharge, no light sensitivity and no change in vision. Some people notice mild itchiness, dryness or a faint gritty sensation from the surface irritation, which lubricating drops can soothe. The eyelids and eye movements are normal. Because the bleed sits on the surface, it looks dramatic but the eye usually feels entirely fine and the appearance settles on its own within one to two weeks, sometimes a little longer for larger patches.
Common causes of a subconjunctival haemorrhage
A subconjunctival haemorrhage happens when a tiny conjunctival capillary breaks. The most common triggers are sudden pressure changes, minor knocks or surface irritation, but sometimes no cause is found. Certain medicines and health conditions also make these delicate vessels more likely to bleed. Understanding your likely trigger can help you decide whether simple home care is enough or whether you should be checked.
- Straining/Valsalva: coughing, sneezing, vomiting or constipation.
- Heavy lifting or bending forward.
- Minor eye trauma or rubbing.
- Contact lens wear and surface friction.
- Recent eye surgery or injections.
- Head or eye injury.
- Blood-thinning medicines: e.g. warfarin, aspirin, clopidogrel.
- Health conditions: high blood pressure, diabetes, clotting disorders.
- No clear cause (idiopathic): common and usually harmless.
Even when there’s no obvious trigger, a subconjunctival haemorrhage is usually benign — what matters are the warning signs, which we outline next.
Is a subconjunctival haemorrhage serious?
A subconjunctival haemorrhage is rarely serious. For most adults, it’s the eye’s version of a bruise: superficial, painless and self‑resolving within one to two weeks. Because the blood lies under the conjunctiva rather than inside the eye, it doesn’t harm the cornea, iris or your vision.
Seek urgent care if you notice any of the following:
- Eye pain, light sensitivity or any change in vision (blur, double vision, a shadow).
- A recent significant eye or head injury, or something struck the eye at speed.
- Recurrent episodes, a very large bleed, or bleeding elsewhere (nose/gums) — especially if you take blood thinners such as warfarin, aspirin or clopidogrel.
- A visible pool of blood in front of the coloured part of the eye, or a misshapen pupil.
- Marked swelling, pus-like discharge, a bulging eye, or trouble moving the eye.
If none of these apply, monitor at home. Have your blood pressure checked — hypertension commonly contributes — and don’t change any prescribed anticoagulant or antiplatelet medication without medical advice. If bleeds keep returning, book a routine review to look for underlying causes and tailored prevention.
How long does a subconjunctival haemorrhage last?
Most subconjunctival haemorrhages clear without treatment in 1–2 weeks. They often begin to fade within a few days. Like a skin bruise, the colour shifts from bright red to maroon and then a yellowish tint as the blood is re‑absorbed. Larger patches can take longer to clear. The redness sits on the surface and doesn’t involve the cornea or the inside of the eye, so your vision stays normal while it heals.
If you take blood thinners (warfarin, aspirin, clopidogrel), resolution can take up to 3 weeks — don’t stop medication unless your doctor advises. See a clinician if it isn’t fading after two weeks, hasn’t cleared by three weeks, keeps recurring, or you develop pain, discharge or any change in vision. It’s also sensible to have your blood pressure checked, as hypertension commonly contributes.
Treatment and home care
For an uncomplicated subconjunctival haemorrhage, treatment is simple: time and comfort. The blood sits under the conjunctiva like a skin bruise and your body re‑absorbs it over 1–2 weeks. There’s no drop that clears it faster. Focus on soothing the surface and keeping the eye comfortable while it heals.
- Lubricating drops: Use artificial tears as needed for dryness or a gritty feeling; preservative‑free tears are a good choice.
- Cool compress: Apply a clean, cool compress for a few minutes at a time to ease surface irritation.
- Contacts: If you wear contact lenses and the eye feels irritated, switch to glasses until it settles.
- Medicines: Keep taking your prescribed medicines; don’t stop blood thinners such as warfarin or aspirin without medical advice.
- Blood pressure: Arrange a quick blood pressure check, especially if you haven’t had one recently or if bleeds recur.
- Pain relief: Most people don’t need painkillers because a subconjunctival haemorrhage usually isn’t painful.
Expect the colour to shift from bright red to yellow as it clears — that’s normal. If the patch isn’t fading after two weeks, or you develop pain, discharge or any change in vision, arrange a review.
What to avoid while your eye heals
While a subconjunctival haemorrhage is usually harmless, a few simple don’ts can prevent re‑bleeding and reduce irritation. Think of it like a bruise on the eye’s surface: give it time, keep it comfortable, and avoid anything that puts extra pressure on the delicate surface vessels.
- Rubbing or touching the eye: This can restart bleeding; use lubricating drops instead.
- Contact lenses if irritated: Switch to glasses until the eye feels normal and redness is fading.
- Straining and heavy lifting: Avoid forceful coughing, heavy lifting and straining on the toilet; manage constipation.
- Prolonged head‑down positions: Minimise bending forward or head‑down work for a few days.
- High‑risk activities: Pause contact sports and DIY tasks that risk knocks to the eye.
- Changing blood thinners: Don’t start or stop blood‑thinning medicines (e.g. aspirin, warfarin, clopidogrel) without medical advice—continue as prescribed.
When to see a doctor or go to emergency
Most subconjunctival haemorrhages can be watched at home. If you’re unsure, use the checklist below to decide between urgent and routine care. When in doubt — particularly after an injury or if you notice vision symptoms — it’s safer to be seen promptly.
Go to the Emergency Department (ED) or call triple zero (000) now if you have:
- Severe eye pain, sudden vision changes or marked light sensitivity.
- A significant eye or head injury, especially a high‑speed impact.
- Blood in front of the coloured part of the eye (not just on the white) or a misshapen/teardrop‑shaped pupil.
- A bulging eye, marked swelling, copious pus‑like discharge, or trouble moving the eye.
- Other unusual bleeding or widespread bruising, particularly if you take blood thinners.
Book a same‑day or next‑day appointment (GP, optometrist or ophthalmologist) if you have:
- Persistent discomfort, light sensitivity or blurred vision.
- Recurrent episodes or both eyes being affected repeatedly.
- No improvement after 10–14 days, or it hasn’t cleared by three weeks.
- Contact lens wear with pain, discharge or increasing irritation.
- High blood pressure or diabetes and you’ve not had a recent check — arrange a blood pressure review.
- Children: any episode after an injury, or if both eyes are involved or there are other facial bruises.
Don’t stop prescribed anticoagulants or antiplatelet medicines without medical advice. If you’re unsure where your situation fits, call your GP or optometrist for triage; if symptoms are severe or sudden, head straight to ED.
How a subconjunctival haemorrhage is diagnosed
Diagnosis is usually straightforward. Your GP, optometrist or ophthalmologist recognises the bright, sharply edged red patch on the sclera with normal vision and no discomfort, and confirms there’s no discharge or corneal involvement. History and examination focus on likely triggers (strain, minor trauma, contact lenses, blood thinners) and, crucially, on ruling out injury or other causes of red eye.
- Basic eye exam: Visual acuity and pupils; quick check of cornea/anterior chamber to confirm it’s superficial.
- Slit‑lamp and fluorescein (if indicated): When there’s pain, trauma, contact lens wear or atypical features, to rule out abrasion or other injury.
- Blood pressure: Checked in all patients; hypertension is a common contributor.
- Medicines and tests: If you take warfarin, an INR may be checked. Broader blood tests are usually reserved for recurrent cases or other bleeding/bruising.
- Further imaging: Dilated retinal exam or scans are rarely needed unless another diagnosis is suspected.
Risk factors and recurrence
Anyone can have a subconjunctival haemorrhage, but some people are more prone because the tiny surface vessels are fragile or under extra pressure. Ageing and vascular conditions play a big part, as do certain medicines and ocular surface factors like contact lenses or recent eye surgery.
- High blood pressure (hypertension): a leading contributor.
- Diabetes and vascular disease: including hyperlipidaemia.
- Blood-thinning medicines: e.g. warfarin, aspirin, clopidogrel; other drugs can occasionally do the same.
- Contact lens wear: dryness and friction increase risk.
- Recent eye surgery or injections: e.g. cataract or refractive surgery.
- Straining/Valsalva: coughing, sneezing, vomiting, constipation, heavy lifting.
- Clotting disorders: such as haemophilia or von Willebrand disease.
- Older age (especially 65+): vessels are more fragile over time.
Recurrence is common: about 1 in 10 people without obvious risk factors will have another episode, and the rate is higher if you take blood thinners or have hypertension/diabetes. If bleeds keep returning, have your blood pressure checked, review medicines with your doctor, and consider targeted tests if there’s other easy bruising or bleeding.
Prevention tips to reduce the chance of future episodes
You can’t prevent every subconjunctival haemorrhage, but you can reduce repeat episodes by protecting the eye’s surface and avoiding pressure spikes that burst tiny vessels. Most steps are simple lifestyle tweaks that also support heart and eye health. If haemorrhages keep recurring, book a routine review to check blood pressure, medicines and any underlying causes.
- Keep blood pressure in range: regular checks and management with your GP.
- Don’t rub your eyes: use preservative‑free artificial tears for dryness/itch.
- Reduce pressure spikes: treat coughs, avoid straining; manage constipation.
- Lift smart: exhale during effort; avoid heavy lifting and prolonged head‑down poses.
- Optimise contact lens habits: meticulous hygiene, correct fit; switch to glasses if irritated.
- Wear protective eyewear: for sport, yard work and DIY to prevent minor trauma.
- Review blood‑thinning medicines with your doctor: never stop them on your own.
- Manage vascular risks: good control of diabetes and cholesterol supports fragile vessels.
Special situations: contact lenses, blood thinners, children and after eye surgery
Most subconjunctival haemorrhages are straightforward, but a few scenarios need tailored advice. Contact lens wearers, people taking blood thinners, children, and anyone who has recently had eye surgery or injections should know what’s typical, what’s not, and when to seek review.
Contact lenses
Contact lenses can dry and rub the conjunctiva, making tiny vessels more likely to break. If you develop a haemorrhage, switch to glasses until the eye feels normal and the redness is clearly fading. Ensure meticulous lens hygiene and a good fit; if episodes recur, have your lenses and ocular surface assessed before resuming wear.
Blood thinners
Warfarin, aspirin and clopidogrel increase the chance of a subconjunctival haemorrhage and it may take longer to clear (often up to three weeks). Do not stop these medicines without medical advice. If bleeds are frequent or you notice other easy bruising/bleeding, see your GP to review therapy (including an INR if you’re on warfarin) and check for underlying clotting issues.
Children
In newborns, a subconjunctival haemorrhage after vaginal delivery is relatively common and usually harmless, resolving on its own. In older children, any episode after eye/head injury should be examined. Bilateral haemorrhages with facial petechiae can signal non‑accidental trauma — arrange prompt medical assessment. Pain, light sensitivity or vision changes always warrant urgent review.
After eye surgery or injections
Small surface bleeds are common after cataract or refractive surgery, sub‑Tenon’s anaesthesia and intravitreal injections. They look dramatic but are usually benign and settle within one to two weeks. Follow your post‑operative plan, avoid rubbing, and contact your surgeon if you develop pain, blurred vision, increasing redness/discharge, or if the haemorrhage isn’t improving.
Subconjunctival haemorrhage versus other causes of red eye
Not every red eye is a subconjunctival haemorrhage. The giveaway for a haemorrhage is a sharply defined, bright red patch on the white of the eye with normal vision and little to no discomfort or discharge. By contrast, many other conditions cause diffuse redness, pain, light sensitivity or blurred vision. A ring of redness around the cornea (ciliary flush) points to inflammation inside the eye and needs prompt assessment.
- Conjunctivitis: diffuse redness with irritation and discharge; often affects both eyes, and the redness isn’t a single, well‑demarcated blood patch.
- Episcleritis: sectoral redness with mild ache; usually self‑limiting but can mimic a small haemorrhage.
- Scleritis (urgent): severe, deep eye pain and tenderness; redness is not a discrete blood patch.
- Corneal problems (abrasion/ulcer/keratitis) (urgent): pain, light sensitivity and a gritty or foreign‑body sensation; higher risk in contact lens wearers.
- Iritis/anterior uveitis (urgent): photophobia and aching with a ciliary flush; vision can be affected.
- Acute angle‑closure glaucoma (emergency): a painful red eye with reduced vision; requires immediate care.
- Hyphema (urgent): blood pooling in front of the coloured part of the eye, not on the white.
- Trauma/open globe (emergency): after impact, look for severe pain, reduced vision or a teardrop‑shaped pupil.
If your red eye is painful, light‑sensitive, sticky, or blurring your vision, don’t assume it’s a subconjunctival haemorrhage—get it checked promptly.
Care in Sydney’s Eastern Suburbs: how Bright Sight Eye Specialists can help
If you’ve woken with a vivid red patch in one eye, you want reassurance and a careful check for red flags. At Bright Sight Eye Specialists in Randwick, Dr Rahul Dubey and team provide timely, compassionate assessment for subconjunctival haemorrhage — from one‑off episodes to recurrences — including red eyes after surgery or injections, for patients across Randwick, Maroubra, Bondi, Waverley and Kensington.
- Expert assessment: Slit‑lamp examination to confirm a subconjunctival haemorrhage, rule out hyphema, corneal abrasion or uveitis, and check vision.
- Health check and prevention: Blood pressure reading, medication review (including blood thinners) and tailored prevention advice.
- Lens and surface care: Contact lens fit/hygiene review, management of dryness, and a safe return‑to‑lens plan.
- Post‑op guidance: Reassurance and follow‑up for expected small surface bleeds after cataract/refractive surgery or intravitreal injections.
- Urgent care pathway: If warning signs are present (trauma, pain, vision change), rapid escalation to appropriate treatment with retinal and surgical expertise on hand.
- Transparent costs: Clear fees with known‑gap or no‑gap options for insured procedures.
Most subconjunctival haemorrhages need only reassurance and lubricants — and if anything more is uncovered, you’re already with the right team for definitive care.
FAQs about subconjunctival haemorrhage
Here are quick answers to the questions patients ask most. If your situation isn’t covered here — or you have pain, light sensitivity or any change in vision — arrange a prompt review to rule out other causes of a red eye.
- Is it contagious? No. It’s a small surface bleed, not an infection.
- Will it affect my sight? No. Vision should stay normal; if it blurs, get seen urgently.
- How long will it last? Usually 1–2 weeks; up to 3 weeks if you’re on blood thinners.
- Do I need drops or antibiotics? There’s no drop that clears it faster. Use artificial tears for comfort; antibiotics aren’t needed unless there’s infection.
- Can I keep wearing contact lenses? Prefer glasses until irritation settles and the redness is fading.
- Why has the red turned yellow? It’s normal blood breakdown — like a fading bruise.
- Should I check my blood pressure? Yes. Hypertension commonly contributes; have it checked, especially if episodes recur.
- Does recurrence mean something serious? Often not. About 1 in 10 recur without clear risk factors; frequent episodes warrant a medical review (including medicines like warfarin, aspirin or clopidogrel).
Key takeaways
A subconjunctival haemorrhage is the eye’s version of a bruise: dramatic looking, usually harmless and self‑resolving. Vision stays normal and there’s typically no pain. Most clear in 1–2 weeks. Soothe with artificial tears and a cool compress, avoid rubbing and heavy straining, and keep taking prescribed medicines. Check your blood pressure and seek care if anything seems atypical.
- Superficial: under the conjunctiva; vision normal, usually no pain.
- Timeline: 1–2 weeks; up to 3 on blood thinners; not clearing by 2–3 weeks? Get reviewed.
- Triggers/risks: strain, minor trauma, contact lenses; hypertension, diabetes, age; blood‑thinning medicines.
- Home care: artificial tears, cool compress; avoid rubbing/straining; continue prescribed medicines.
- Urgent signs: pain, vision change, major trauma, hyphema/teardrop pupil, bulging eye or pus.
For reassurance or a prompt red‑eye check in Sydney’s Eastern Suburbs, contact Bright Sight Eye Specialists.