For one in four people, the arrival of warmer weather marks the beginning of an annual struggle against hay fever. Some sufferers swear by a yearly 'hay fever injection', offered by some private clinics. But is it effective? And more importantly, is it safe?
Hay fever is caused by an allergic reaction to pollen. When it comes into contact with the mouth, eyes, nose or throat, the body reacts by making specific antibodies. Hay fever affects people at different times depending on which pollen they are allergic to. The majority of people are allergic to grass pollen, so will experience their worst symptoms between May and June; tree pollen affects people in late spring between March and May; while others are affected by weed and mould pollens in the autumn.
The condition is characterised by sneezing and coughing, a runny or blocked nose, red watery eyes, itchy throat, mouth, nose, eyes or ears, headaches and sometimes a feeling of fatigue or tiredness. Sufferers may also experience a wheeze and tightness in the chest.
Many people manage their symptoms by taking simple steps to stop the pollen reaching them - wraparound sunglasses to protect the eyes, or Vaseline around the nostrils - or by taking over-the-counter antihistamine drops or tablets, and using a nasal spray.
How does the hay fever jab work?
For around 10% of people though, these medications do not relieve their symptoms and some of them opt for the hay fever jab, a steroid injection marketed as Kenalog. It works by suppressing the body's immune response to histamines and thus relieving symptoms.
"Sufferers of hay fever may consider the hay fever injection, offered by some private clinics," explains Dr Farah Gilani, a Medicspot GP. "This is an injection of a steroid called triamcinolone into a large muscle in the body. Once the steroid is injected, it slowly leaks from the muscle for three to eight weeks and travels throughout the body, theoretically offering relief from hay fever symptoms."
Gilani says there are many anecdotal accounts by individuals who report significant improvements in their symptoms with this injection. David Clare from Lincolnshire has had positive results.
"I get the steroid injection for hay fever every year, although my GP only allows one course per year, due to the side effects," states Clare. "I find getting it just before the worst month (which is August, for me) is best, and keeps my symptoms at bay for a month. During this time, I feel just as I would in autumn and winter, so it is a quite a relief!"
Clare still has to take antihistamines either side of the injection, but says that over-the-counter and prescribed medicines have never really worked for him.
"Only the jab does the job," he adds. "For that reason, I find it worth the cost and the potential side effects (of which I've never experienced any)."
What are the downsides?
The injection was historically available on the NHS, explains Gilani, but it is no longer offered due to a lack of robust evidence supporting its efficacy.
Plus, the treatment can cause a potentially long list of side effects including raised blood pressure, water retention, skin rashes and muscle weakness. Other unwanted secondary effects include swelling, breathing difficulties, abdominal pain, insomnia and taste disturbance.
"Once the steroid has been injected, nothing can be done to prevent it from spreading through the body over the following weeks, even if side effects are experienced," states Gilani. "In addition, it is contra-indicated in some patients, such as those who have stomach ulcers, diabetes or an active infection."
For these reasons, charity Allergy UK does not endorse the injection. "The steroid injection is not recommended as it is a high-dose steroid given by an intramuscular injection and once injected, the amount of steroid cannot be removed and it comes with a high side-effect profile.
"Many patients like it as it does help with their hay fever symptoms and that is why you can get it privately, but it is not given on the NHS in allergy services as the recommendations are to give immunotherapy for severe hay fever," their spokesperson continues.
Chief pharmacist Stuart Gale at Oxford Online Pharmacy adds: "Kenalog is only safe and recommended for use in a small group of people, as intramuscular steroids can exacerbate existing medical conditions. The mainstay of treatment is oral antihistamines, nasal sprays and eye drops."
While it might seem convenient simply to have a single injection rather than having to take tablets every day, there is a lack of strong evidence that supports its effectiveness. GPs and pharmacists recommend conventional treatments such as topical and oral antihistamines, nasal steroids and eye drops.
For those who do experience severe symptoms, immunotherapy - which involves injecting a small amount of pollen under the skin to help build up immunity - is recommended. This usually begins in the winter, around three months before the hay fever season starts. Its aim is to desensitise the body to the allergen so it doesn't react so severely, and although it won't cure hay fever, it will make the symptoms milder and could mean you require less medication.