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Side effects of mometasone nasal spray

NHS medicines information on side effects of mometasone and what you can do to cope.

About this information

This NHS content is written for people in England. Medicine names, availability, prescribing and services may differ in other countries.

Common side effects

These common side effects of mometasone nasal spray may happen in more than 1 in 100 people. There are things you can do to help cope with them:

Headaches

Make sure you rest and drink plenty of fluids. Do not drink too much alcohol. Ask your pharmacist to recommend a painkiller. Talk to your doctor if the headaches are severe.

Unpleasant taste or smell

Rinsing your mouth out with water or brushing your teeth after you use your nasal spray may help.

Sneezing

This will usually settle down as you get used to the medicine.

Nosebleeds, dry or sore nose or throat

If you have nosebleeds, or mometasone is making your nose or throat dry or sore, stop using it for a few days then start again.

Speak to your doctor or a pharmacist if this advice does not help and the side effects still bother you or do not go away.

Serious side effects

Very few people have serious side effects when using mometasone nasal spray.

You're more likely to have a serious side effect if you use high doses of mometasone for more than a few months.

Call a doctor or call 111 straight away if you get:

  • eye problems such as pain or blurred vision – these can be signs of increased pressure in your eyes (glaucoma) or a cataract
  • problems such as nose pain, sores inside your nose or nosebleeds that do not stop

Serious allergic reaction

In rare cases, mometasone may cause a serious allergic reaction (anaphylaxis).

Meds New IA (H4) - serious allergic reaction

Call 999 now if:

  • your lips, mouth, throat or tongue suddenly become swollen
  • you're breathing very fast or struggling to breathe (you may become very wheezy or feel like you're choking or gasping for air)
  • your throat feels tight or you're struggling to swallow
  • your skin, tongue or lips turn blue, grey or pale (if you have black or brown skin, this may be easier to see on the palms of your hands or soles of your feet)
  • you suddenly become very confused, drowsy or dizzy
  • someone faints and cannot be woken up
  • a child is limp, floppy or not responding like they normally do (their head may fall to the side, backwards or forwards, or they may find it difficult to lift their head or focus on your face)

You or the person who's unwell may also have a rash that's swollen, raised, itchy, blistered or peeling.

These can be signs of a serious allergic reaction and may need immediate treatment in hospital.

Other side effects

These are not all the side effects of mometasone nasal spray. For a full list see the leaflet inside your medicines packet.

View the original NHS website page ↗. Refreshed 19 August 2026.

Licensed under the Open Government Licence v3.0 ↗. MyPHU is independent and is not endorsed by the NHS.

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