Hay fever season is well under way and millions are expecting to avoid streaming noses and itchy eyes with their usual antihistamine pills.
Except some are unobtainable. Search for Piriton Allergy Tablets for adults on the Boots website and you’ll see the message: ‘We’re sorry, this product has sold out and we won’t be receiving any further stock.’
It’s a similar message on the Lloyds Pharmacy and Co-op Pharmacy websites.
The reason for the shortage, affecting Piriton and other products, is that a key ingredient, chlorphenamine maleate, is in short supply.
Hay fever symptoms begin when immune cells, B lymphocytes, mistakenly identify pollen proteins as a threat and make antibodies that trigger chemicals called histamines
‘It’s a bad time for this,’ says Sid Dajani, a pharmacist based in Hampshire. ‘Many people rely on these drugs.’
There is also concern as chlorphenamine, an antihistamine, is a common treatment for anaphylaxis, a severe allergic reaction. ‘There is no antihistamine as effective,’ says Sid Dajani.
Hay fever symptoms begin when immune cells, B lymphocytes, mistakenly identify pollen proteins as a threat and make antibodies that trigger chemicals called histamines.
These make the blood vessels dilate, prompting the release of fluid from capillaries, triggering a runny nose, sneezing and weeping eyes.
The chlorphenamine shortage has been blamed on logistical problems, as well as disruption caused by the war in Ukraine.
Also, many suppliers are in China, where 345 million people are living under lockdowns, including in Shanghai — the world’s largest port.
Search for Piriton Allergy Tablets for adults on the Boots website and you’ll see the message: ‘We’re sorry, this product has sold out and we won’t be receiving any further stock’
A Boots spokesman said: ‘We have a range of hay fever relief medicines, with good availability of stock overall. A small number of lines are currently out of stock due to a current, industry-wide shortage of chlorphenamine maleate. However, we are expecting this to be resolved soon.’
If you can’t find your usual brand, Sid Dajani suggests looking for own-brand chlorphenamine maleate tablets, which may still be available.
Other brands that contain the antihistamine cetirizine hydrochloride are available — for instance, Piriteze, Benadryl, Allacan — he says. ‘There are also own-brand products that have different antihistamines.’
The National Institute for Health and Care Excellence says antihistamines such as loratadine cause less drowsiness than chlorphenamine. Products containing loratadine include Clarityn and Boots One-a-Day Allergy Relief 10mg tablets.
Boots Hayfever and Allergy Relief and Benadryl Allergy One-a-day 10mg tablets contain cetirizine, which is unlikely to make you drowsy. Benadryl Relief contains a non-drowsy antihistamine, acrivastine.
The reason for the shortage, affecting Piriton and other products, is that a key ingredient, chlorphenamine maleate, is in short supply. Boots hayfever and allergy relief tablets are pictured above
But some people choose chlorphenamine because it helps them sleep through their symptoms at night. Sid Dajani says adults who can’t get Piriton but need the sleep effect could take Nytol, which contains the antihistamine diphenhydramine.
For now, liquid formulas for children containing chlorphenamine are still available, including Piriton syrup. Other options include Clarityn Allergy syrup for children aged two and over, which contains loratadine.
Children under 12 can sometimes be prescribed cetirizine. ‘Benadryl Allergy for Children oral solution, which also comes in chewable form, contains diphenhydramine, which is still available,’ says Sid Dajani.
Whatever remedy you choose, he says, antihistamines take two to three days to have an effect, so should be taken before problems start.