Clarinex is a hay fever treatment that can help relieve symptoms like runny nose, watery eyes and sneezing. It’s an antihistamine that works by calming your immune system and doesn’t cause drowsiness. When taken, Clarinex begins working in three hours and can last up to 24 hours.[1]
Hay fever is a common condition that affects millions of people worldwide. It’s primarily caused by pollen from grass, trees and weeds. While it’s typically not a serious condition, if you have severe symptoms such as frequent sneezing, watery and itchy eyes, and tiredness, taking a treatment such as Clarinex can help.[2]
If you have asthma, it’s also helpful to take antihistamines as they can prevent symptoms from being triggered.
How does Clarinex work?
Desloratadine, the active drug in Clarinex, is an antihistamine that binds to histamine receptors.
Hay fever is caused by an allergic response to pollen. When pollen enters the body, it’s treated by our defences as a harmful substance, triggering an immune response and producing antibodies. This causes the release of histamine, the chemical responsible for hay fever.
Histamine causes inflammation in the nose, throat and eyes, resulting in symptoms like itchy eyes and runny nose. Desloratadine binds to histamine receptors to stop histamine from creating an allergic reaction, helping to relieve the symptoms.[1]
What versions of Clarinex are there?
Clarinex comes in various forms: a tablet, an oral solution, or an orally disintegrating tablet (Redi-Tab or ODT). Each form is available in a 5mg dose that’s taken once a day.
Schering Corporation (2005). Cologne, Germany: Institute for Quality and Efficiency in Health Care. Overview: Hay fever.
This page was written by The Treated Content Team.
This page was medically reviewed by Dr. Joseph Palumbo on September 16, 2024. Next review due on September 16, 2027.
How we source info.
When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognised analytics or data body. Read more in our editorial policy.
ClarinexDesloratadine
How to take Clarinex
The instructions for taking Clarinex vary slightly depending on the form.
Clarinex Tablet: Take one Clarinex tablet with some water. It can be taken with or without food.
Clarinex Oral Solution: Take 2 ml-2.5 ml of the solution.
Clarinex RediTabs (ODT): Place one tablet on your tongue and allow it to dissolve. You can then swallow it with or without water.
How long does Clarinex take to work?
Clarinex can take one to three hours to work and reaches peak concentration at the three hour mark. It can last 27 hours, which helps provide all day relief from allergy symptoms.[1] It’s best to take Clarinex a couple of hours before you plan to go outside, allowing it to start working before you’re exposed to pollen.
What should I do if I make a mistake when taking Clarinex?
Only take the recommended amount in 24 hours. Taking more than the recommended amount can cause drowsiness. If you take too much, contact your doctor or seek medical attention.
Treated trusted source:
Haye, R., et al (2005). Morning versus evening dosing of desloratadine in seasonal allergic rhinitis: A randomised controlled study. Clinical and Molecular Allergy : CMA, 3, 3.
This page was written by The Treated Content Team.
This page was medically reviewed by Dr. Joseph Palumbo on September 16, 2024. Next review due on September 16, 2027.
How we source info.
When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognised analytics or data body. Read more in our editorial policy.
ClarinexDesloratadine
Clarinex isn’t suitable for everyone, and there are some things that you need to be aware of when taking it.
Here’s all the official info on it. If anything is unclear, let our clinician know, and they can talk with you about it.
ClarinexDesloratadine
Clarinex: FAQ
Have something specific you want to know? Search our info below, or ask our experts a question if you can’t find what you’re looking for.
Is there a generic version of Clarinex available?
Answer:
Yes, Clarinex is the branded medicine of the drug desloratadine. There isn't much difference between the generic and branded versions, except in the non-active ingredients, the manufacturing company, the forms and the price. Desloratadine is only available as an oral tablet, if you struggle to take tablets, then Clarinex oral solution and Redi-tabs might be better for you. Aside from that, the one you choose is up to you, but the generic version is usually cheaper.
What’s the difference between Clarinex and Claritin?
Answer:
Claritin is another allergy treatment that contains the drug loratadine. Both Clarinex and Claritin are second-generation antihistamines that work similarly to alleviate allergy symptoms. They’re also available as a generic medication.
When comparing the two, Claritin works faster, typically within one hour, compared to Clarinex which can take up to three hours. Both can last between 12-24 hours and are generally non-drowsy. Studies have shown that desloratadine is more potent than loratadine, but this doesn't necessarily mean it’s more effective.[1]
Is Clarinex available over the counter?
Answer:
No, you will need a prescription for Clarinex from your doctor. This is to ensure it’s safe and effective for you to take.
What are the side effects of Clarinex?
Answer:
As with all medications, there is a risk of experiencing side effects when taking Clarinex, including:
dry mouth,
sore throat,
muscles pain,
sleepiness,
tiredness, and
menstrual pain.
Clarinex is a second-generation antihistamine, which is less likely to cause drowsiness and sleepiness. However, an individual's reaction to the medicine can vary. If you feel drowsy when taking it, contact your doctor and they might suggest an alternative treatment.
Can I have alcohol while taking Clarinex?
Answer:
You can drink alcohol while taking Clarinex, but it’s best to avoid it as it can increase the chances of feeling drowsy and sleepy. While Clarinex is a non-drowsy antihistamine, alcohol might increase the risk of some of the side effects.
How is Clarinex different from Zyrtec?
Answer:
Like Clarinex, Zyrtec is an allergy medication containing cetirizine, another antihistamine. It’s quite similar to Clarinex but there are a few differences. Zyrtec works within one hour whereas Clarinex takes three hours. They both last up to 24 hours. While both are considered non-drowsy, Zyrtec is more likely to cause drowsiness.[2]
Treated trusted source:
Geha, R.S. and Meltzer, E.O. (2001). Desloratadine: A new, nonsedating, oral antihistamine. Journal of Allergy and Clinical Immunology, 107(4), pp.751–762.
NHS (2021). Cetirizine: antihistamine that relieves allergy symptoms. FAQ: What’s the difference between cetirizine and other non-drowsy antihistamines? Nhs.uk.
Last updated on Sep 15, 2024.
How we reviewed this page:
Our experts continually monitor new findings in health and medicine, and we update our articles when new info becomes available.
Sep 15, 2024
Published by: The Treated Content Team.Medically reviewed by: Dr. Joseph Palumbo, Senior Medical Adviser
How we source info.
When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognised analytics or data body. Read more in our editorial policy.
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Dr. Joseph Palumbo
Senior Medical Adviser
Joseph joined Treated in 2023, and is one of the lead doctors providing prescribing services for the platform.
When we present you with stats, data, opinion or a consensus, we’ll tell you where this came from. And we’ll only present data as clinically reliable if it’s come from a reputable source, such as a state or government-funded health body, a peer-reviewed medical journal, or a recognised analytics or data body. Read more in our editorial policy.
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