In treating allergies or a cold with antihistamines , you may experience drowsiness, a common side effect of the medication. How does this happen? Histamine is a chemical produced by the immune system to fight off allergens and germs. When there is a threat of allergies or infection such as the common cold , histamine is even more active. In its search-and-destroy process, it can cause allergy or cold symptoms such as runny nose, coughing, sneezing and itch eyes.
Antihistamine medications relieve these symptoms by blocking the unwanted effects of histamine. Unrelated to the immune system, histamine is also produced in the brain, where it plays an important part in feeling awake.
Antihistamines used to treat respiratory symptoms can get into the brain and interrupt this work, making you feel drowsy. Some antihistamines are less likely to cause drowsiness than others.
Reactions vary considerably from one person to another. What relieves your symptoms without making you sleepy may be different from what works for someone else. When you find one that works for you, stick with it — check chemical ingredients and dosages before changing brands or generics. During pregnancy, they are preferred over Allegra, which has shown adverse fetal effects in animal studies.
Allegra is considered to be safer for breastfeeding mothers compared to Zyrtec and Claritin. However, all three are deemed to be safe during lactation. All three antihistamines may cause side effects such as:. That said, the side effect profile may vary slightly among them. For instance, Allegra is completely non-sedating doesn't make people sleepy , while Claritin is minimally sedating makes only a small number of people sleepy.
Zyrtec, on the other hand, causes sedation in approximately one in six people who take the medication. While you should consult your healthcare provider about the best way to take any medication, there are widely accepted dosing recommendations for all three of these antihistamines.
First and foremost, each works best when taken daily rather than intermittently. All of these antihistamines are indicated for adults and children 2 years of age and older, with Zyrtec and Claritin dosed once a day for all ages.
Allegra is dosed twice a day for children age 2 to 11, and once a day for adults and children age 12 years and older. Finally, since Allegra can be used in children as young as 6 months of age, it's sometimes the ideal choice for young children. Besides dosing, there are some slight differences in how quickly or well the drugs work. For example, while Claritin is effective for treating hay fever and hives, other antihistamines, such as Zyrtec and Allegra, work better and faster and last longer.
Zyrtec and Allegra work quickly for the treatment of allergic rhinitis and hives, typically within less than an hour. On the other hand, studies show that Claritin takes many hours to start working. Studies show that Allegra is nearly as good as Zyrtec at treating hayfever.
However, Zyrtec and its isomer Xyzal levocetirizine appear to be better medicines for the treatment of hives. There are also some unexpected nuances associated with each of the antihistamines. For example, if you're taking Allegra, it's important to avoid drinking fruit juice for one to two hours before you take the medication and one to two hours after.
Juices such as orange juice or grapefruit juice can decrease the absorption of Allegra by nearly half. The best antihistamine choice for any one person is based on the degree of symptom relief desired and the degree of side effects you're willing to tolerate.
For mild to moderate allergy symptoms, Allegra may be preferable to drugs such as Zyrtec since these other drugs are more sedating. Yet for severe symptoms that are interfering with work, school, or play, a medication such as Zyrtec may be needed. Note that every person is different. This means that despite what studies say, there are many people who do not experience any fatigue on Zyrtec or Xyzal.
Likewise, there are people who do experience fatigue on Allegra. It's sometimes helpful to try different medications to see which works best for you as an individual. If you try this, though, talk with your healthcare provider first.
You might keep a journal to get an objective measure of which drug works best. For instance, you can write down your most annoying symptoms, and rank them from 1 to 10 based on how well they are controlled by different medications.
Talk with an allergist about the possibility of allergy testing and allergy shots. While allergy shots require more follow-up and more pokes they can sometimes cure allergies or at least significantly reduce their symptoms so that medications are no longer needed. In addition, it's thought that allergy shots may sometimes help prevent the development of new allergies. If you often forget doses, it may help to set an alarm to remind you.
You could also ask your pharmacist for advice on other ways to help you remember to take your medicine. Fexofenadine is generally very safe. Taking more than your usual dose is unlikely to harm you. If you take an extra dose, you might get some of the common side effects. If this happens or you're concerned, contact your doctor. Like all medicines, fexofenadine can cause side effects, although not everyone gets them. Talk to your doctor or pharmacist if these side effects bother you or do not go away:.
Go to In rare cases, fexofenadine may cause a serious allergic reaction anaphylaxis. These are not all the side effects of fexofenadine. For a full list, see the leaflet inside your medicine packet. Fexofenadine is not usually recommended if you're pregnant as there is not a lot of information about its use in pregnancy. Other antihistamines may be more suitable as better safety information is available. If you think that you need to take fexofenadine in pregnancy, talk to your doctor or pharmacist who will help you decide, or who may recommend other medicines for you.
If your doctor or health visitor says your baby is healthy, you can take fexofenadine while breastfeeding. There is very little information available, but it shows that only tiny amounts get into breast milk.
It is unlikely to cause any side effects in your baby. If you're breastfeeding or planning to breastfeed, talk to your doctor or pharmacist, as other antihistamines called loratadine and cetirizine might be better while you're breastfeeding. If your baby is not feeding as well as usual, seems unusually sleepy, or seems irritable, or if you have any other concerns about your baby, talk to your doctor, pharmacist, health visitor or midwife.
Some medicines and fexofenadine can affect each other and increase the chances of you having side effects. There's very little information about taking herbal remedies and supplements with fexofendadine. There might be a problem taking some herbal remedies and supplements with it, especially ones that cause sleepiness or a dry mouth, or make it difficult to pee. Tell your doctor or pharmacist if you're taking any other medicines, including herbal medicines, vitamins or supplements.
Fexofenadine is a type of medicine called an antihistamine. When you come into contact with something you're allergic to, such as pollen, animal hair or fur, house dust, or insect bites and stings, 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, a running or blocked nose, sneezing and skin rashes.
You may only need to take it as a one-off dose or for a day or two, for example if you have a reaction to an insect bite. You may need to take fexofenadine for longer if you're taking it to prevent symptoms, for example to stop hay fever symptoms when the pollen count is high. Talk to your doctor or pharmacist if you're unsure how long you need to take fexofenadine for.
Fexofenadine is unlikely to do you any harm if you take it for a long time. But it's best to take it only for as long as you need to. It's best not to drink alcohol while you're taking fexofenadine as it can make you feel sleepy. Do not drink grapefruit juice, orange juice or apple juice while taking fexofenadine. It might make you more likely to have side effects. Fexofenadine is classed as a non-drowsy antihistamine, but it's still possible to feel sleepy after taking it.
If you're taking fexofenadine for the first time, see how it makes you feel before driving, cycling, or using heavy machinery or tools. It's an offence to drive a car if your ability to drive safely is affected. It's your responsibility to decide if it's safe to drive. If you're in any doubt, do not drive. Talk to your doctor or pharmacist if you're unsure whether it's safe for you to drive while taking fexofenadine.
UK has more information on the law on drugs and driving. That's because it's less likely to make you feel sleepy than drowsy sedating antihistamines, such as Piriton chlorphenamine. Most people prefer to take a non-drowsy antihistamine instead of a sedating one.
An exception is when you want the medicine to make you sleepy — for example, if you have itchy skin that's keeping you awake.
Other non-drowsy antihistamines like acrivastine , cetirizine , loratadine , desloratadine and levocetirizine seem to work just as well as fexofenadine. But fexofenadine seems to be less likely to make you feel sleepy than other non-drowsy antihistamines. If one non-drowsy antihistamine has not worked for you, it's worth trying another one. Yes, you can take fexofenadine together with paracetamol or ibuprofen.
Sometimes doctors recommend that people with a severe, itchy skin rash take 2 different antihistamines together for a few days. As well as taking a non-drowsy antihistamine during the day such as fexofenadine, cetirizine or loratadine , your doctor may suggest that you take a sedating antihistamine at night time if the itching is making it difficult to sleep. Yes, it's fine to take fexofenadine together with some other hay fever treatments, including steroid nasal sprays such as Beconase, Rhinacort Aqua and Flixonase Nasules or eye drops.
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