How your hay fever medication could be a health hazard – after links to ‘poor brain health’ and heart issues
ITCHY eyes, constant sneezing, a runny nose... all signs hay fever season is well and truly here.
Yep, that joyous time of the year when one in four Brits dreads the smell of freshly-cut grass and ends up spluttering, coughing and rubbing their eyes non-stop if they dare head outside.
The common allergy tends to hit between March and September, when the pollen count from grass and trees is at its highest, and sees sufferers taking antihistamines regularly to reduce symptoms.
However, some research suggests that antihistamines can impact brain health.
And some over-the-counter drugs could be dangerous to people with heart issues.
There are several types of medicines you can take to ease maddening hay fever symptoms - though the three main ones are steroid nasal sprays, antihistamines and decongestants.
So how worried should we be about taking these everyday drugs, when many of us are used to popping them throughout spring and summer? We reveal all.
Antihistamines - the main drug of choice
“ANTIHISTAMINES are used to treat allergies, such as hay fever, conjunctivitis, hives and insect stings,” explains Dr Deborah Lee, from .
“They are also used to treat motion sickness and as a short-term treatment for insomnia.”
You can take them as drops, tablets, sprays and more, and they’re available on prescription as well as over the counter in pharmacies and supermarkets.
Most of us have some Piriton in the cupboard somewhere, they’re that common.
“Antihistamines are used by millions of patients each year for allergic conditions,” says Dr Robin Gore, president of the .
“Many patients with mild allergic diseases only take doses intermittently.
“For patients with more severe allergic disease, clear guidelines exist to help doctors add in other, non-antihistamine therapies to control disease so that allergy sufferers do not simply increase antihistamine doses but seek more effective alternatives.”
There are two key groups of antihistamines according to the : drowsy and non-drowsy.
“First generation antihistamines (FGAs) such as diphenhydramine (Benadryl), chlorphenamine (Piriton) and promethazine (Phenergan) easily cross the blood brain barrier and cause sedation,” says Dr Lee.
“FGAs can have anticholinergic side effects, including dry mouth, dry eyes, dilated pupils and a fast heart rate.”
She adds: “The newer, second-generation antihistamines (SGAs) such as cetirizine (Zyrtec), loratadine (Claritin) and fexofenadine (Allegra) do not enter the brain so easily.
“They are regarded as non-drowsy and have a longer duration of action.”
Dr Gore says: “SGAs include cetirizine, loratadine, desloratadine and fexofenadine and are now widely recommended for patients with allergic conditions.
“They are considered much safer than FGAs and are far less likely to have any sedative effects.”
Antihistamines and memory
IT'S become a topic of conversation after Harvard doctor Anthony L. Komaroff, MD said last month he would “think twice about taking antihistamines and other medicines with anticholinergic effects” when asked .
“I weigh the symptom relief they give me against the possibility that they may slightly increase my risk of developing dementia,” he added.
Drug with anticholinergic side effects have been found to have a possible link with dementia - they may increase brain inflammation or block certain important neurotransmitters - but the research is not conclusive.
“These are either observational or case-controlled studies – research methodology where something has been observed to happen to a specific group of people – but causation cannot be proven," Dr Lee says.
Hay fever symptoms can be extremely unpleasant and significantly lower your quality of life
Dr Deborah Lee
However, FGAs are “no longer routinely recommended for use for allergic diseases”, notes Dr Gore.
, by Chun-Hung Su and co, from the Chung Shan Medical University in Taichung, Taiwan, reported on the effects of taking FGAs and SGAs on the risk of dementia.
The researchers looked at patients who were aged over 50 and had allergic rhinitis.
“The authors report a link between the use of antihistamines and the development of dementia,” says Dr Gore.
“The link they report is strongest for older FGAs than with the newer SGAs.
“They report a dose response: taking higher doses for longer seems to make the link look stronger.”
Because the paper is retrospectively reported, Dr Gore says: “This means that patients are studied ‘in the past’ and this makes it difficult to eliminate biases that may affect the accuracy of the results.
“Other large studies using a range of different methods have investigated many different types of medication and the risk of dementia.
“The results from these studies differ widely."
Best hay fever treatments to buy online
1. Allergy Eye Mist
If you hate the thought of drops, consider an eye mist which works in the same way – just spray it once or twice onto closed eyelids to to three times a day.
Try , is suitable for all types of contact lenses too.
2. Cetirizine Allergy & Hay Fever Tablets
Products containing Cetirizine work to combat allergies without making you feel tired.
comes in at £5.49.
3. Hay Fever Relief Nasal Spray
For over-the-counter relief you could try x 60 Sprays from Superdrug, £8.79.
Or for something on prescription, try
4. Jelly
Dabbing a little bit of petroleum jelly around the edges of your nose works as a barrier to trap pollen before you breathe it in.
Try branded balms such as. Or petroleum jelly such as does just the same job for only a fraction of the price.
5. The Eye Doctor Allergy Hay Fever Compress
The Eye Doctor Allergy Hay Fever Compress has thermal dynamic fabric, which uses regulated evaporation to cool more rapidly.
It helps to reduce puffiness, swelling, itching, inflammation and even headaches, and comes with an adjustable comfy strap.
You can buy it at .
6. Throat spray
Ultra Chloraseptic Anaesthetic Throat Spray contains the active ingredient benzocaine which belongs to the group of medicines called local anaesthetics.
You can buy Ultra .
It's not just memory in older age.
Dr Gore says: "In young people, has highlighted the effects of FGAs on concentration: young people on sedating antihistamines with seasonal rhinitis may suffer lower examination grades."
But he adds: “There is no research in young people to show any long-term irreversible effects of antihistamines on memory.”
“In general people should not be overly worried about this,” says Dr Lee.
“The concern is about long term, frequent - not occasional - use of first generation antihistamines.
“The newer second generation antihistamines are more commonly used these days, and they have no demonstrable anticholinergic effects, so an association with dementia risk is less likely.”
She adds: “Hay fever symptoms can be extremely unpleasant and significantly lower your quality of life.
“For the majority of sufferers, taking a second generation antihistamine for a few months of the year is more likely to confer benefit than harm.”
Nasal sprays and heart health
THERE are two main types of nasal sprays. Steroid nasal sprays, like beclomethasone (Beconase) and budesonide (Benacort), of which some are prescription, and antihistamine sprays.
There are also decongestants which unblock the nose.
But people with pre-existing heart or circulatory issues should be cautious about using nasal sprays, Julie Ward, senior cardiac nurse at the .
This is because some contain pseudoephedrine - a common ingredient in products that unblock the nose, like Sudafed - which constricts blood vessels.
"This can raise your blood pressure and heart rate and cause palpitations," Julie .
If your heartbeat becomes noticeable and you have a fluttering or pounding feeling in your chest, you may be experiencing heart palpitations.
"Because of this, the NHS does not recommend decongestants for anyone with high blood pressure or a heart or circulatory disease," the cardiac nurse said.
"If you need a decongestant, talk to your doctor or pharmacist, and always read the medicine information leaflet before taking a hay fever medication as some combine antihistamines with decongestants.
"If you experience heart palpitations, which feel like your heart is racing or skipping a beat, after taking a hay fever medicine, stop taking it and consult your doctor."
Prolonged use of decongestant nasal sprays can also lead to dependency or worsening symptoms.
Antihistamines and blood pressure
ANTIHISTAMINES like loratadine (Clarityn) and cetirizine (Piriteze) are generally safe for people with high blood pressure and heart and circulatory diseases, Julie said.
They work by blocking chemicals in your blood called histamines that cause hay fever symptoms.
"However, another type of antihistamine, called fexofenadine (Allevia or Telfast), can lead to a fast or irregular heartbeat and you should talk to your doctor or pharmacist before taking it," Julie said.
You should also discuss taking fexofenadine with your GP or phramacist if you have liver or kidney problems.
In people with reduced kidney function, fexofenadine can accumulate in the body, potentially leading to higher-than-normal levels and an increased risk of side effects.
Montelukast and depression
MONTELUKAST is ususally used to prevent the symptoms of asthma but it may also help people with seasonal allergies, like hay fever.
The prescription drug, also known as Singulair, helps stop your airways from narrowing to make breathing easier.
But it can have side effects of mood changes such as depression and anxiety, sleep problems such as nightmares, and changes in your behaviour such as aggression, the NHS says - though this is not common.
There have been 82 suicides linked to montelukast since 1998 in the US, the Food and Drug Administration (FDA) reports.
It’s unclear how many suicides in the UK are linked to montelukast, but the UK’s Medicines and Healthcare Products Regulatory Agency (MHRA) has received around 1,205 reports of psychiatric side effects tied to the drug since 1998.
The montelukast UK action group is calling for more prominent warnings of the drug’s possible side effects.
The NHS says to call 999 if you have thoughts of harming yourself while taking montelukast, while Asthma + Lung UK say to tell your GP or doctor if you have a mental health issue, like deression or anxiety.
"If montelukast is a new medicine for you, your GP, nurse or other healthcare professional should check how you're getting on with it after eight to twelve weeks," it says.
Should you change your medication?
DON’T suddenly bin your medications.
Dr Gore says: “Based on current evidence, people with allergic disease who need to use second generation antihistamine tablets (SGAs) such as loratadine, fexofenadine, cetirizine, desloratadine, or the nasal spray azelastine (often given in a combination dose with a nasal steroid) should not stop taking them.
“Allergy sufferers with poorly controlled rhinitis and who are only using antihistamine tablets - especially as we move into spring and summer, peak times for tree pollen allergic rhinitis and grass pollen hay fever - should speak to their pharmacist about other medications to improve symptoms.
"People on any long term antihistamine on repeat prescription should have this medication reviewed at their next annual medication review, to ensure that they are on an appropriate medication.
“Patients using FGAs should get advice from their GP or pharmacist if they are at all concerned.
“There are alternatives available and GPs and pharmacists can help.”
