Noticed a bright red patch on the white of your eye and worried it’s a sign of something serious? That striking mark is most often a subconjunctival haemorrhage — a tiny burst blood vessel under the clear surface layer (the conjunctiva). Despite how dramatic it looks, it usually doesn’t hurt, won’t blur your vision, and clears on its own within one to three weeks. Many people search “blood in whites of eyes” for this exact reason.
This guide explains what you’re seeing, the common triggers (from a cough or sneeze to rubbing your eye), how long it lasts, what actually helps at home, and when a red eye signals something more urgent. We’ll also cover who’s at higher risk, prevention tips, look‑alike conditions, and when to book an appointment with an eye specialist in Sydney’s Eastern Suburbs.
What you’re seeing: typical signs and symptoms
A subconjunctival haemorrhage shows up as a sharply defined, bright red patch on the white of the eye. It often looks dramatic but is usually painless, with no light sensitivity, discharge or blurred vision. You might notice a slight scratchy or “awareness” feeling, especially if the surface is dry. As it heals, the colour can shift from red to brown and then yellow, like a fading bruise.
- Bright red patch: Flat and well‑outlined on the sclera.
- One eye only: Most cases are unilateral.
- No vision change: Reading and driving should feel normal.
- Usually no pain: At most mild irritation or itch.
- Colour fade: Red to brown/yellow over 1–3 weeks.
What causes a blood spot on the white of the eye
A subconjunctival haemorrhage is a tiny surface vessel that has burst beneath the clear conjunctiva. The usual culprits are brief pressure spikes (a hard cough, sneeze or strain on the toilet) or minor trauma/irritation (eye rubbing or contact lens friction). It can follow eye surgery, be more likely with certain medicines and health conditions, and sometimes no cause is found. If you woke with “blood in whites of eyes,” one of the following is often behind it:
- Straining/pressure spikes: Coughing, sneezing, vomiting, constipation, heavy lifting or bending.
- Minor trauma or rubbing: Accidental poke, vigorous eye rubbing, sports knocks.
- Contact lenses: Dryness or friction from lenses increasing surface irritation.
- Recent eye surgery/procedures: For example, after cataract surgery.
- Medicines that thin blood: Warfarin, aspirin; some cancer drugs (interferon).
- Health conditions: High blood pressure, diabetes, blood‑clotting disorders.
- Conjunctival inflammation/dryness: Makes vessels more fragile and itchy.
- No clear trigger: Many cases are idiopathic and still harmless.
Is it serious? when a red eye is more than a burst vessel
Most “blood in whites of eyes” patches are benign. But a red eye needs prompt care if key warning signs are present. If any of the following apply, arrange same‑day assessment with your GP, optometrist or urgent care; severe cases should go to emergency.
- Eye pain: Subconjunctival haemorrhage is usually painless; pain needs review.
- Vision changes: Blurred vision, shadowing or reduced sight.
- Recent eye or head injury: Especially high‑speed or penetrating trauma.
- Blood inside the eye (hyphema): Pooling in front of the iris is an emergency.
- Discharge or marked light sensitivity: Not typical for a burst surface vessel.
- Frequent episodes or easy bruising/bleeding: Particularly if on blood thinners.
- Not improving by 2–3 weeks: Or if the red area enlarges.
How long it lasts and what healing looks like
Most subconjunctival haemorrhages settle without treatment in about 1–2 weeks, and up to three weeks for larger patches. As the “blood in whites of eyes” clears, the sharp red area softens and the colour fades like a bruise — bright red to brown, then yellow, before the white returns to normal. Your vision should remain unchanged throughout. If the patch isn’t steadily improving after two weeks, or persists beyond three, arrange a check‑up.
What helps at home (and what to avoid)
If you’ve noticed blood in the whites of your eyes, home care is about comfort and patience. There’s no drop or ointment that clears it faster; your body reabsorbs the blood over 1–3 weeks. If the surface feels scratchy, lubricating eye drops (artificial tears) can soothe the dryness and irritation.
- Use artificial tears: As needed; choose preservative‑free if using often.
- Don’t rub or press: Avoid rubbing and protect the eye from further knocks.
- Minimise straining: Ease cough/constipation and skip heavy lifting for a few days.
- Contacts bothering you? Switch to glasses until the eye feels comfortable.
- Keep medicines consistent: Do not stop blood thinners or aspirin without medical advice.
When to see a doctor or go to urgent care
Most burst surface vessels are safe to watch, but don’t ignore warning signs. Arrange same‑day review with your GP or optometrist, and head to the emergency department for severe symptoms. Seek medical care promptly if any of the following apply.
- Eye pain: Subconjunctival haemorrhage is usually painless.
- Vision changes or light sensitivity: Blur, shadowing, double vision, or photophobia.
- Recent injury: Eye or head trauma, high‑speed sports knock, or suspected foreign body.
- Blood pooling in front of the iris: A hyphema is an emergency.
- Recurrent episodes or bleeding tendency: Frequent patches, easy bruising/bleeding, or taking blood thinners — get checked (don’t stop medicines without advice).
- Slow recovery: No improvement after 2–3 weeks, or the red area is enlarging.
How subconjunctival haemorrhage is diagnosed
Most cases are diagnosed on the spot with a simple eye examination. Your clinician will confirm the flat, sharply outlined red patch under the conjunctiva and make sure there’s no pain, discharge or vision change that points to another problem. They’ll ask about recent coughing, sneezing, straining, eye rubbing, injuries and medicines (especially blood thinners), and look for signs of trauma.
- Basic eye exam: Visual check and history.
- Slit‑lamp assessment: To exclude surface injury or other red‑eye causes.
- Blood pressure check: Commonly done, particularly if bruising/bleeding elsewhere.
- Further tests if recurrent: Blood tests for clotting disorders or medication review.
- Urgent referral after injury/pain/blur: To rule out complications such as hyphema.
Who is at higher risk
Anyone can get a subconjunctival haemorrhage, but risk is higher with older age (especially 65+), high blood pressure or diabetes, and if you take blood‑thinning medicines such as warfarin or aspirin or have a bleeding/clotting disorder. Contact lens wearers and people with dry eye or who rub their eyes a lot are more prone, as are those soon after eye surgery (for example, cataract procedures). Frequent straining from coughing, constipation or heavy lifting also increases the chance of seeing “blood in whites of eyes”.
How to prevent it and reduce recurrences
You can’t always stop a tiny surface vessel from bursting, but smart habits make recurrences less likely. Reduce surface irritation, avoid short bursts of pressure, and stay on top of cardiovascular risks. If you’re seeing “blood in whites of eyes” repeatedly, book a review to check for contributing causes.
- Avoid rubbing: Use artificial tears to settle dryness and itch.
- Manage straining: Treat constipation or cough; skip heavy lifting for a bit.
- Contact lenses: Optimise fit and hygiene; switch to glasses if irritated.
- Protect your eyes: Wear safety eyewear for sport, DIY and work.
- Check health and medicines: Monitor blood pressure/diabetes; review blood thinners—don’t stop without advice.
Special situations: blood thinners, contact lenses, children and pregnancy
Some situations call for tailored advice when you notice blood in the whites of your eyes. Most are still harmless, but a brief check or simple tweak can aid comfort and reduce recurrences.
- Blood thinners: You’re more prone to a subconjunctival haemorrhage. Don’t stop aspirin or anticoagulants without medical advice; seek review if episodes are frequent or large, and have your blood pressure checked.
- Contact lenses: Switch to glasses until comfortable, use lubricating drops, and review lens fit and hygiene with your optometrist before resuming wear.
- Children: Often follows coughing, sneezing or rubbing and settles on its own. If there’s pain, an injury, or repeat episodes, see a doctor.
- Pregnancy/childbirth: Vomiting or straining in labour can trigger a harmless patch. If recurrent, discuss with your antenatal team and check blood pressure.
Conditions that look similar but are different
A bright, flat, sharply outlined red patch suggests a subconjunctival haemorrhage, but not all red or bloody-looking eyes are the same. Noticing pain, discharge, light sensitivity or blurred vision points away from a simple burst surface vessel and toward other causes that need different care.
- Hyphema: Blood pooling in front of the iris; pain and blurred vision. Emergency.
- Conjunctivitis: Red, gritty or itchy eye with discharge and sticky lashes.
- Corneal abrasion/keratitis: Sharp pain, tearing, marked light sensitivity.
- Uveitis (iritis): Aching eye, photophobia and blur; needs prompt treatment.
- Scleritis: Severe, deep eye pain and tenderness; often wakes you at night.
- Acute angle‑closure glaucoma: Sudden pain, halos, headache, nausea, vision loss.
- Episcleritis/pinguecula/pterygium: Localised redness or fleshy patch, mild discomfort—not a sharp blood spot.
Can I keep working, exercising, flying or driving?
Seeing blood in the whites of your eyes shouldn’t stop everyday life. For a simple subconjunctival haemorrhage, most people can keep working, exercising gently, flying and driving because vision isn’t affected. If you’re comfortable and have no pain or blur, it’s safe to continue, but go easy for 48–72 hours to avoid straining. Switch to glasses if contacts irritate, and stop activity if symptoms develop.
- Work/drive: OK if vision is comfortable and unchanged.
- Exercise: light only; avoid heavy lifting/straining.
- Flying: safe; use artificial tears.
When to see an eye specialist in Sydney’s Eastern Suburbs
Book an eye specialist review if the red patch follows trauma, is painful, affects vision, recurs (especially on blood thinners), or hasn’t improved after 2–3 weeks. In Sydney’s Eastern Suburbs, Bright Sight Eye Specialists (Randwick) can assess subconjunctival haemorrhage, check for contributing risks (blood pressure, medicines), and exclude serious causes such as hyphema or uveitis. Seek urgent same‑day care for sudden pain, blur or blood pooling.
The bottom line
Most “blood in whites of eyes” spots are simple subconjunctival haemorrhages — dramatic to look at, harmless in most cases, and gone within 1–3 weeks. Soothe with artificial tears, avoid rubbing, and seek care if there’s pain, vision change, trauma, frequent recurrences, or slow healing. If you’re in Sydney’s Eastern Suburbs and want reassurance or a same‑day check, contact Bright Sight Eye Specialists.