The advice applies to patients who are taking the common antihistamine for hay fever or allergies
Amber O’Connor Money and Lifestyle reporter U35s
11:57, 05 Feb 2026
The NHS guidance is displayed on the website (stock photo)(Image: Getty)
The NHS has advice for people in the UK taking a common antihistamine for allergies. The health service urges people to avoid certain drinks, as they may interfere with medication and reduce its effectiveness, according to the latest guidance on its website.
The warning is relevant to anyone who takes fexofenadine, which is often sold under the brand names Allevia, Almerg, Histallay, Telfast, and Treathay. Fexofenadine is an antihistamine which blocks the effects of histamine and reduces uncomfortable symptoms such as itchy eyes and sneezing.
According to the NHS: “When you come into contact with something you’re allergic to, such as pollen, animal hair or fur, house dust or you have an insect bite or sting, your body produces a chemical called histamine. Usually, histamine is a useful substance but in an allergic reaction it causes unpleasant symptoms including itchy, watery eyes, running or blocked nose, sneezing and skin rashes.”
Available on prescription and over the counter, fexofenadine is used for conditions such as hay fever, hives, eczema, conjunctivitis, and food allergies. Fexofenadine is often a popular choice because it is non-drowsy, though some people might still feel sleepy after taking it.
The medicine is a tablet, with three strengths available: 30mg, 120mg and 180mg. Adults usually take 120mg once a day when treating hay fever. However, on some occasions, your doctor or pharmacist may suggest taking a higher dose. Always take your medicine as advised by the pharmacist or doctor, and speak to a medical professional about any concerns you might have.
Drinking certain fruit juices could stop the medicine from working properly (stock photo)(Image: Getty)
The NHS has a ‘fruit juice’ alert to people who take it. In a statement on its website, the NHS says: “Do not take your tablets with apple, orange or grapefruit juice as these can reduce how well the medicine works. Swallow them whole – do not chew them.”
If you take antihistamines like fexofenadine with apple, orange, or grapefruit juice, it can really lower how well your body absorbs the medicine, making it less effective by about 30% to 70%. These juices have stuff in them that stops important transporters in your intestines from working, which means the medicine can’t get into your bloodstream the way it should.
The advice says to take the tablet with water. The NHS states: “If you’re taking 30mg fexofenadine tablets, you can take them with or without food. If you’re taking 120mg or 180mg fexofenadine tablets, take them before a meal.” It is always wise to check the leaflet that comes with all medication for any warnings or side effects.
The NHS website shares advice for anyone taking the tablets (stock photo)(Image: Getty)
While the NHS website does not list any other food or soft drinks to avoid while taking the medicine, it does advise people not to drink alcohol. The NHS says: “It’s best not to drink alcohol while you’re taking fexofenadine, as it can make you feel sleepy.”
You should also tell your doctor if you’re taking any other medicines, including herbal remedies, vitamins or supplements. The NHS says there isn’t enough information to know whether it is safe to take supplements, complementary medicines, or herbal remedies with fexofenadine, reports the Mirror.
The advice explains: “They’re generally not tested for the effect they have on other medicines. However, there might be a problem with some of them, especially ones that cause sleepiness, a dry mouth, or make it difficult to pee.”