Short answer
Cataract surgery removes the eye’s natural lens after it has become cloudy and replaces it with a clear artificial lens, called an intraocular lens (IOL).1 It is usually done under local anaesthetic as a day case, and serious complications are uncommon.12 It treats the cloudiness only: it cannot restore sight lost to other eye conditions, and many people still need glasses afterwards.2 Whether and when to operate depends on how much the cataract affects daily life and on the health of the rest of the eye, which requires examination.2
| Question | Summary |
|---|---|
| What it is | Phacoemulsification: ultrasound breaks up the cloudy lens, which is removed and replaced with an IOL12 |
| Anaesthesia | Usually local anaesthetic drops, sometimes with an injection; you stay awake12 |
| Operation time | Around 20 minutes; 20 to 45 minutes in NHS guidance12 |
| Feeling normal | Most people within two to three days; full healing about 4 to 6 weeks23 |
| Commonest later problem | Posterior capsule opacification: about 1 in 3 within five years, treated with laser2 |
| Serious complications | About 1 in 1,000, including retinal detachment and infection2 |
| Lens on the NHS | Monofocal; toric and multifocal or EDOF lenses mostly private2 |
On this page
- What cataract surgery is and how it works
- What may be causing the change in vision
- Who may be considered
- Alternatives
- Procedure, preparation and anaesthesia
- Recovery and results timeline
- How long results last
- Pain and comfort
- Risks and complications
- How strong is the evidence?
- Lens and technique distinctions, and red flags
- Cost drivers and what a quote should include
- Frequently asked questions
- Bottom line
- Related reading
- Sources
What cataract surgery is and how it works
A cataract is clouding of the lens behind the pupil, which causes blurred or misty vision and can lead to loss of sight.1 Almost all cataract surgery in the UK uses phacoemulsification.2 The surgeon makes tiny incisions, uses an ultrasound probe to break up the cloudy lens, removes the fragments by suction, and places a folded IOL inside the thin capsule that held the natural lens.13 The incisions usually seal without stitches.3
What may be causing the change in vision
Most cataracts are age-related and develop after 65, although some people develop them in their forties or fifties.2 Other recognised causes and risk factors include diabetes, steroid medicines, eye injury, previous retinal surgery, uveitis (inflammation inside the eye), glaucoma and very high short sight; children can also have cataracts, which are managed differently.2 Typical symptoms are glasses that seem dirty, misty vision, glare from headlights and faded colours.2
Not all blurred vision is cataract. Other eye conditions can coexist with a cataract, and replacing the lens cannot restore sight lost to them, so a full examination of the whole eye comes before a decision.
Who may be considered
Surgery can be considered at any stage when the cataract affects day-to-day activities such as reading, using a screen or driving; there is no need to wait for it to ripen.2 The benefit should outweigh the small risk of surgery, and delaying does not permanently harm vision, although very dense cataracts can be harder to remove.2 Difficulty driving is one of the everyday problems that may prompt surgery.2
Who may not benefit or may face additional risk
- People whose sight is limited mainly by another eye condition, who may gain less.2
- People with diabetes, who often develop cataracts earlier, or with other eye conditions such as uveitis or glaucoma, where there may be more concern about complications.2
- People with very dense cataracts, which are harder to remove.2
When a responsible clinician may advise against it
Alternatives
None of the sources we checked describe a medicine or eye drop that clears a cataract; they describe surgery as the treatment once the cataract affects daily life.12 In the meantime, an up-to-date glasses prescription and good lighting may help, and the practical alternative to surgery now is surgery later.
No treatment is a legitimate option
Waiting is reasonable while vision still meets your needs. Delay does not cause permanent damage, so the timing can be your choice, guided by how much the cataract affects you.2
Procedure, preparation and anaesthesia
Before surgery the eye is measured (biometry) to calculate the lens power, and the choice of distance or near focus is discussed. On the day, most people have local anaesthetic drops, sometimes with an injection; general anaesthesia is reserved for particular situations.12 The operation usually takes around 20 minutes, and it is a day case, so plan to be at the hospital for about half a day.2 You should not drive yourself home.2
Usually one eye is done at a time, starting with the worse eye.2 Both eyes may be done on the same day if there are no complicating factors, and this is usually safer when general anaesthesia is needed.2 NICE guideline NG77 recommends same-day surgery on both eyes only for low-risk patients.4
| Lens type | What it does | Trade-offs |
|---|---|---|
| Monofocal | Clear vision at one distance, usually far; offered on the NHS23 | Reading glasses usually needed2 |
| Toric | Monofocal design that also corrects astigmatism23 | Not usually available on the NHS; NICE judged it unlikely to be cost-effective routinely24 |
| Multifocal or EDOF (extended depth of focus) | Aims to cover more than one distance, reducing glasses use23 | Haloes, glare and reduced contrast; may be hard to remove; NG77 advises against routine use45 |
Recovery and results timeline
Vision may be blurry for a few hours, and the eye may ache for a few days.1 Most people feel back to normal within two to three days, and full healing takes around 4 to 6 weeks.23 Eye drops are usually used for about 4 weeks, and the course should be finished.12 A follow-up check is usually arranged around 4 to 6 weeks after surgery.2
| Activity | Typical guidance |
|---|---|
| Driving | Once vision meets the legal standard; many people can drive soon after12 |
| Work | Depends on the job; the surgeon will advise2 |
| Swimming | Avoid, even with goggles, during recovery12 |
| Heavy lifting, sport, eye make-up | Avoid until the eye has recovered or the doctor advises otherwise1 |
| New glasses | After the second eye, wait about six weeks2 |
How long results last
The artificial lens does not become cloudy and is intended to stay in place for life. However, the capsule behind it can thicken over months or years, called posterior capsule opacification (PCO); about 1 in 3 patients develop it within five years.2 It is treated with a short outpatient laser procedure (YAG laser capsulotomy).23 NICE notes that lens material may influence PCO rates, with hydrophobic and possibly silicone lenses having lower rates.4
Pain and comfort
Under local anaesthetic you stay awake but should not feel pain during the operation.1 Afterwards the eye may hurt for a few days, and a protective shield may be advised, especially at night.13 The NHS suggests painkillers such as paracetamol if needed, and advises getting a red or painful eye checked by an optician.1
Risks and complications
| Category | Examples |
|---|---|
| Expected temporary effects | Blurred vision for hours to days, aching, light sensitivity; negative dysphotopsia (a dark crescent shadow) often settles within weeks12 |
| Recognised complications | PCO; macular oedema (fluid at the centre of the retina), which often resolves; ongoing swelling or inflammation; positive dysphotopsia (streaks or starbursts) that may persist23 |
| Rare serious complications | About 1 in 1,000: retinal detachment, lens position problems, a break in the lens capsule, and infection inside the eye (endophthalmitis)23 |
Endophthalmitis is rare but can threaten sight. An antibiotic injected into the eye at the end of surgery (intracameral cefuroxime) was associated with a large fall in infection in a French hospital series, from 35 of 2,826 patients to 1 of 2,289.6 That study was not randomised and its starting infection rate was higher than the overall figure given by the RCOphth.26
Warning signs that need urgent help
The NHS advises urgent help through NHS 111 for sudden new or more floaters, flashes of light, a dark curtain or shadow across vision, or sudden blurring, which may signal a detached retina.1 A red or painful eye, blurry or cloudy vision, or light or dark areas in vision should be checked by an optician.1
How strong is the evidence?
| Claim | Vireon assessment | What supports it | Important limitation |
|---|---|---|---|
| Surgery improves vision when cataract is the main cause | Strong | National guidance and professional information24 | Benefit is smaller when other eye disease is present |
| Multifocal IOLs reduce glasses use but cause more haloes and glare | Moderate | NICE overview including a systematic review of 10 randomised trials5 | 2008 review; lens designs have changed |
| PCO affects about 1 in 3 within five years | Moderate | RCOphth patient information2 | Varies with lens material and follow-up length |
| Intracameral antibiotic reduces endophthalmitis | Limited | Single-hospital before-and-after study6 | Not randomised; high baseline rate |
| Toric IOLs are cost-effective for routine use | Insufficient | NICE research recommendation4 | Update on lens selection under way |
Patient-information figures are rounded averages. Individual risk depends on eye health, cataract density and other conditions, and NICE has said it will update its lens-selection recommendations.4
Lens and technique distinctions, and red flags
The main choices are the lens type and whether both eyes are treated on the same day. Premium lenses can reduce glasses use but bring trade-offs in night vision and contrast that some people find hard to accept.5 Laser-assisted variations exist, but our sources did not assess them, so they are not compared here.
- Pressure to have surgery before the cataract affects daily life.2
- Multifocal lenses offered without discussion of haloes, glare and reduced contrast.5
- Same-day surgery on both eyes without a clear reason.4
- No plan for follow-up at 4 to 6 weeks or for managing PCO later.2
Cost drivers and what a quote should include
Cost depends mainly on the lens type, whether one or both eyes are treated, the anaesthetic, the surgeon and facility, and follow-up. A quote should list pre-operative measurements, the named lens model and power, drops, all follow-up visits, the plan and cost if PCO laser treatment or further surgery is needed, and what happens if a complication requires extra care.
If you are travelling for treatment
- Biometry and a full examination of both eyes must be done in person before surgery.2
- Check that you will not be driving yourself after surgery.2
- UK CAA guidance for health professionals suggests about one week before flying after intra-ocular procedures, and much longer if gas was placed in the eye (about 2 weeks for sulphur hexafluoride and 6 weeks for perfluoropropane); it does not name cataract surgery specifically, so confirm with the surgeon.7
- Plan follow-up at home at around 4 to 6 weeks, and take the lens details with you.2
- Know where to go urgently at home if retinal detachment symptoms appear.1
Questions worth asking a clinician
- How much of my poor vision is due to the cataract, and how much to anything else?
- Which lens do you suggest, and what distance will it focus at?
- Will I need glasses for reading or distance afterwards?
- Will you treat one eye at a time, and how long between eyes?
- What steps do you take to prevent infection?
- Who treats PCO if it develops later?
Frequently asked questions
Does cataract surgery hurt?
You should not feel pain during the operation because of the local anaesthetic, although the eye may ache for a few days.1
How long until my vision feels normal?
Most people feel back to normal within two to three days, with full healing at about 4 to 6 weeks.23
When can I drive and return to work?
You can drive once your vision meets the legal standard, and return to work depends on the job.12
When can I fly?
There is no cataract-specific rule in the CAA guidance; it suggests about one week after intra-ocular procedures without gas, so check with your surgeon.7
Will the cataract come back?
No, but about 1 in 3 people develop clouding of the capsule behind the lens within five years, which a quick laser treatment can clear.2
Are both eyes done at once?
Usually not; one eye is treated at a time, with same-day surgery reserved for selected cases.24
Bottom line
Cataract surgery reliably restores clarity when the cloudy lens is the main problem, but it cannot fix other eye disease and often does not remove the need for glasses. The lens choice, rather than the operation itself, is where most of the trade-offs lie.
Related reading
Sources
- NHS. Cataract surgery. NHS website; page last reviewed 6 March 2025. https://www.nhs.uk/tests-and-treatments/cataract-surgery/ Accessed 5 November 2026.
- RNIB and The Royal College of Ophthalmologists. Understanding Cataracts. RNIB/RCOphth; 2025. https://www.rcophth.ac.uk/wp-content/uploads/2026/09/APDF-SE180804_Understanding-Cataracts-2025-v01.pdf Accessed 5 November 2026.
- American Academy of Ophthalmology (AAO). Cataract Surgery: Risks, Recovery, Costs. AAO; 2026. https://www.aao.org/eye-health/diseases/what-is-cataract-surgery Accessed 5 November 2026.
- National Institute for Health and Care Excellence (NICE). May 2025 surveillance of cataracts in adults: management (NICE guideline NG77). NICE; 2025. https://www.nice.org.uk/guidance/ng77/resources/may-2025-surveillance-of-cataracts-in-adults-management-nice-guideline-ng77-pdf-19904868830149 Accessed 5 November 2026.
- National Institute for Health and Care Excellence (NICE). Implantation of multifocal (non-accommodative) intraocular lenses during cataract surgery (HTG170, formerly IPG264). NICE; 2008. https://www.nice.org.uk/guidance/htg170 Accessed 5 November 2026.
- Barreau G, Mounier M, Marin B, Adenis JP, Robert PY. Intracameral cefuroxime injection at the end of cataract surgery to reduce the incidence of endophthalmitis: French study. Journal of Cataract and Refractive Surgery; 2012;38(8):1370–1375. https://doi.org/10.1016/j.jcrs.2012.03.024 Accessed 5 November 2026.
- UK Civil Aviation Authority (CAA). Surgical conditions (guidance for health professionals on assessing fitness to fly). CAA. https://www.caa.co.uk/passengers/before-you-fly/am-i-fit-to-fly/guidance-for-health-professionals/surgical-conditions/ Accessed 5 November 2026.
Article history
- — First published.