Anti-infective
Nystatin (oral thrush)
Antifungal mouth treatment — Treats oral thrush by acting directly in the mouth.
Education and reference only. This is a plain-language class overview — it deliberately contains no doses. Always check the current Summary of Product Characteristics (SmPC), the BNF and your local formulary before prescribing or administering any medicine.
Quick answer
What is Nystatin (oral thrush)?
Nystatin is an antifungal liquid (and pastille) used to treat oral thrush — a candida infection in the mouth. It works on contact in the mouth rather than being absorbed into the body.
- How it works: It binds to the fungal cell membrane and damages it, killing the candida where it is applied.
- In practice: In practice nystatin is a common treatment for oral thrush (a candida infection causing white patches and soreness in the mouth), working locally because it is barely absorbed from the gut.
What it is
Nystatin is an antifungal liquid (and pastille) used to treat oral thrush — a candida infection in the mouth. It works on contact in the mouth rather than being absorbed into the body.
How it works
It binds to the fungal cell membrane and damages it, killing the candida where it is applied. Because almost none is absorbed from the gut, it acts locally in the mouth with minimal effect on the rest of the body.
In practice
In practice nystatin is a common treatment for oral thrush (a candida infection causing white patches and soreness in the mouth), working locally because it is barely absorbed from the gut. The practical key to success is contact time and technique: the liquid is used after food and after any inhaler, swirled around the whole mouth and held in contact with the affected areas before swallowing, and nothing is eaten or drunk for a short while afterwards so it is not washed away. The course is completed and continued for a couple of days after symptoms clear to prevent relapse. Because oral thrush often has a trigger, this is also a prompt to address the cause — for example rinsing the mouth and using a spacer with inhaled steroids, cleaning dentures, or considering diabetes or immune problems where thrush is recurrent or severe. Extensive, recurrent or swallowing-related thrush may need an oral systemic antifungal instead.
Examples
Practical use
How to take it & use it well
- It works by direct contact with the affected areas, so swirl it around the whole mouth and hold it there before swallowing, rather than swallowing it straight down.
- Use it after food and after any inhaler, and avoid eating or drinking for a short while afterwards so it stays in contact with the infection.
- Keep using it for the full recommended course and continue for a short time after the thrush looks better, as stopping early lets it return.
- If you wear dentures, clean them well and treat them too where advised, since they can harbour the yeast and cause reinfection.
- If you use a steroid inhaler, rinse your mouth or use a spacer to reduce the chance of thrush coming back.
- Shake the bottle if instructed, measure with the device provided, and store as directed on the label.
Common uses
- Oral thrush (oral candidiasis)
- Thrush associated with inhaled steroids, dentures or dry mouth
- Prevention in some at-risk groups (specialist)
Monitoring
- Resolution of the thrush
- Underlying triggers (inhaled steroids, dentures, dry mouth, diabetes/immune status)
- Recurrence needing further treatment
Weighing it up
Advantages & disadvantages
Advantages
- It treats oral thrush directly in the mouth with very little absorbed into the body.
- Because it is barely absorbed, it has few interactions with other medicines.
- It is generally well tolerated and suitable across a wide range of ages.
- It targets the infection at the source when held in the mouth as directed.
- It is a useful option for people who cannot take treatments by mouth that act through the bloodstream.
Disadvantages
- It only works where it touches, so it must be swished thoroughly around the whole mouth to be effective.
- It needs to be used several times a day and timed around food and inhalers, which takes discipline.
- Thrush often returns if the underlying trigger, such as inhaler technique or dentures, is not addressed.
- Some people dislike the taste or texture.
- It is less suited to infection that has spread beyond the mouth, which may need treatment taken into the bloodstream.
Key safety principles
What to watch for
- Works by contact — use after food/inhalers, swirl and hold in the mouth, and avoid eating or drinking for a short while after.
- Complete the course and continue a little after symptoms clear to prevent relapse.
- Address the trigger (inhaler technique/spacer, denture care); extensive, recurrent or swallowing-related thrush may need a systemic antifungal.
Key interactions
What to avoid or check alongside
- Because almost none is absorbed, it has very few interactions with other medicines taken by mouth.
- Eating or drinking too soon after a dose washes it away before it can act.
- Continuing to use a steroid inhaler without rinsing or a spacer encourages the thrush to come back.
- Untreated dentures can reinfect the mouth even after a course is completed.
Patient & carer advice
- Use it after meals and after your inhaler, swish it around and hold it in your mouth before swallowing
- Do not eat or drink for a short while afterwards
- If you use a steroid inhaler, rinse your mouth and use a spacer to help prevent thrush
Answers
Nystatin (oral thrush): frequently asked questions
How should I use nystatin for oral thrush?
Use it after food and after any inhaler, swirling and holding it around your whole mouth before swallowing. Avoid eating or drinking for a short while afterwards so it stays in contact with the infection.
How long should I keep using it?
Complete the full course and continue for a short time after the thrush appears to have cleared. Stopping as soon as it looks better is a common reason it comes back.
Why does my oral thrush keep returning?
Recurrent thrush is often linked to triggers such as steroid inhaler use, dentures, dry mouth or other health conditions. Addressing these, alongside treatment, helps prevent it returning.
Does nystatin interact with my other medicines?
Very little nystatin is absorbed into the body, so it has few interactions with other medicines. Even so, always tell your pharmacist about everything else you take.
Can I eat straight after taking it?
It is best to avoid eating or drinking for a short while after a dose, so the medicine stays in contact with the affected areas long enough to work.
Authoritative sources
Always verify against the source
This overview is for orientation. For doses, interactions, contra-indications and the full monograph, use:
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