Many people living with long-term smell loss are told they have chronic rhinosinusitis, a condition that causes ongoing inflammation in the nose and sinuses. This often comes with congestion, post-nasal drip, headaches, or facial pressure. But one of the most disruptive symptoms is the loss or distortion of smell.
So what does the research say about why this happens, and what might help?
A recent review gathered the latest evidence on how chronic rhinosinusitis (CRS) affects our sense of smell and what treatments are proving most effective.
What Is Chronic Rhinosinusitis?
CRS is more than just a stuffy nose. It’s a long-lasting condition where the tissues in your nose and sinuses stay inflamed for months or even years. It’s quite common, and smell loss is one of the most reported symptoms.
In fact, around 60 to 80% of people with CRS experience some kind of smell dysfunction. For some, it means everything smells dull. For others, smells become distorted or unpleasant. And for many, scent disappears altogether.
Why Does It Affect Smell?
There are two main reasons smell can be affected in CRS:
- Obstruction – The passage to the smell receptors (called the olfactory cleft) can become blocked by swelling or polyps, stopping smells from getting through.
- Inflammation – The nerve endings involved in smell can become inflamed or damaged, which can also reduce smell function.
What Treatments Can Help?
The most widely used and well-researched treatment is corticosteroids. These are anti-inflammatory medications, often given as a nasal spray, and sometimes as oral tablets for short-term use.
Here’s what the evidence says:
- Nasal steroid sprays (like mometasone) are usually the first-line treatment for CRS. They’re generally safe for long-term use and can help reduce swelling and improve smell function.
- Oral steroids may be more effective than sprays in the short term, especially when symptoms are severe. However, they’re usually prescribed for short courses due to possible side effects.
- Surgery might be needed in some cases, especially when polyps or other obstructions are blocking airflow to the smell receptors.
- Smell training is still recommended as a supportive strategy alongside other treatments.
What About Side Effects?
Topical steroid sprays are generally very safe. The most common side effect is nasal bleeding, especially if the spray is used incorrectly (e.g. directed at the nasal septum).
Oral steroids can have stronger side effects if used long term, so doctors usually prescribe them for short periods when needed.
Key Takeaway
If you have smell loss due to chronic rhinosinusitis, there’s good evidence that steroid sprays can help, especially when inflammation is part of the problem.
They may not work instantly, and they’re not a cure – but they’re often part of the first step in managing symptoms, improving airflow, and supporting recovery.
As always, speak to your GP or ENT specialist about what’s best for your situation.
Want to dive deeper?
This blog is based on findings from a recent review:
“Mechanisms, diagnosis, and treatment of olfactory dysfunction in rhinosinusitis” – Hai Zhu, Siyuan Qu, Mengdan Gong, Yizhen Xiang, Shengqi Gan, Yaoshu Teng and Dong Ye.
