A potent steroid eye drop
Dexamethasone (eye drops)
A potent prescription steroid eye drop used in short, supervised courses to settle inflammation inside or on the surface of the eye.
What is Dexamethasone (eye drops)?
Dexamethasone eye drops are a strong steroid used to calm inflammation in the eye, such as after surgery or in certain uveitis. They are prescription-only and used for short, closely supervised courses, because steroids in the eye can raise eye pressure, encourage cataract and worsen some infections. They are not a treatment for an undiagnosed red eye bought without advice.
Education and reference only. This is a plain-language guide to Dexamethasone (eye drops) — it deliberately contains no doses. Doses depend on the person, the brand and the reason for treatment, and belong with your prescriber. Always check the BNF, the product labelling (SmPC) and follow medical advice.
What it is
Dexamethasone eye drops are a potent corticosteroid applied directly to the eye. They are prescribed to dampen inflammation of the surface or front of the eye — for example after eye surgery, or in some types of uveitis (inflammation inside the eye). Because they are powerful, they are prescription-only in the UK and are used under the supervision of a doctor or optometrist rather than self-treated.
How it works
Like other steroids, dexamethasone calms the body's inflammatory response. Applied to the eye, it reduces the redness, swelling, pain and watering that come with inflammation by quietening the immune cells and chemical signals involved. It treats the inflammation itself rather than any underlying cause, which is why an accurate diagnosis matters before it is started.
Company & origin
Originated / developed by: Originally developed by Merck (MSD)..
Dexamethasone was developed in the late 1950s and has long been used as a topical corticosteroid, including in formulations for the eye.
Practical use
How to take Dexamethasone (eye drops)
General, dose-free guidance — always follow your prescriber's and the leaflet's specific instructions.
- Wash your hands, tilt your head back and pull down the lower lid to make a small pocket for the drop.
- Aim the drop into the pocket without letting the bottle tip touch your eye or lashes, then close the eye gently.
- If you wear contact lenses, ask your prescriber — they are usually removed before use and not worn during treatment.
- If you use more than one eye drop, leave a short gap between them so each has time to be absorbed.
- Use only for the course you have been given and attend any eye-pressure checks; do not extend it on your own.
Weighing it up
Advantages & disadvantages of Dexamethasone (eye drops)
Advantages
- Potent and fast at settling inflammation in or on the eye.
- Acts locally at the site of inflammation, so body-wide steroid effects are limited.
- Well established and widely used in eye care, including after surgery.
Disadvantages
- Can raise the pressure inside the eye and encourage cataract with longer or repeated use.
- Can worsen eye infections — dangerous if used on an undiagnosed red eye.
- Prescription-only and needs supervision, so not suitable for casual self-treatment.
Practical use
Good to know
Dexamethasone is a potent steroid, so it is used for the shortest effective course and tapered off rather than stopped abruptly when courses are longer. Steroids in the eye can quietly raise the pressure inside the eye (a glaucoma risk) and encourage cataract over time, so eye-pressure checks may be arranged for longer use. They can also mask or worsen eye infections — particularly herpes simplex (a 'dendritic' ulcer) — so they must never be used in an undiagnosed red or painful eye. It is important to finish only the course your prescriber sets and to attend follow-up.
Who should not take it / use with caution
- People with an undiagnosed red, painful or sticky eye, where an infection has not been ruled out.
- People with certain eye infections — especially viral (herpes simplex), fungal or untreated bacterial eye infections.
- People with raised eye pressure or glaucoma, who need careful monitoring or an alternative.
Monitoring
- Eye pressure during longer or repeated courses
- The eye's appearance and your symptoms at follow-up
- Signs of infection or any change in vision, which should be reported promptly
Side effects
- Brief stinging or blurring just after the drop goes in.
- A rise in the pressure inside the eye, which may cause no symptoms but is checked for during longer use.
- With prolonged use, cataract formation and slower healing, or worsening of an unrecognised eye infection; on a damaged eye surface, rarely thinning or perforation of the cornea.
Key interactions
- Other eye drops can be used together but should be spaced out so each is absorbed.
- Tell your prescriber about any antiviral or antibiotic eye treatment, as a steroid may be unsuitable or need pairing carefully.
- Generally few whole-body interactions because little is absorbed, but mention all your medicines to your prescriber.
Available as: Eye drops; some preparations are also available as single-use units without preservative.
Answers
Dexamethasone (eye drops): frequently asked questions
Can I buy dexamethasone eye drops over the counter?
No. Dexamethasone is a potent steroid and is prescription-only in the UK. A red eye can have many causes — including infection — and using a steroid on the wrong problem can make it much worse, so it is only started after a proper eye examination.
Why does my optometrist want to check my eye pressure?
Steroid eye drops can quietly raise the pressure inside the eye in some people, which over time is a risk for glaucoma. The check is painless and simply makes sure the treatment is safe to continue, particularly during longer courses.
Can I wear my contact lenses while using them?
Usually not. Contact lenses are generally removed during treatment, both because of the eye condition being treated and because some drops contain preservatives. Ask your prescriber when it is safe to wear them again.
Why must I not use them on a red eye without advice?
A red, painful eye can be caused by infection, including herpes simplex, which a steroid can dramatically worsen. That is why these drops are only used once a clinician has examined the eye and confirmed a steroid is appropriate.
What is the difference between dexamethasone and Maxidex?
They are the same medicine — dexamethasone is the active-ingredient name and Maxidex is one brand of the eye-drop preparation. Both contain the same active steroid.
The wider class
About Corticosteroid eye drops
Dexamethasone (eye drops) belongs to the corticosteroid eye drops class. For how the class as a whole works, its shared safety principles and monitoring, see the full guide.
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Authoritative sources
- BNF: Dexamethasone (eye).
- NICE CKS: Steroid eye drops.
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