Clarinex (desloratadine) is an antihistamine used to relieve allergy symptoms. It comes as a tablet and orally disintegrating tablet (ODT). Clarinex (desloratadine) is typically less likely to cause side effects, like sleepiness, than some other antihistamines, such as diphenhydramine (Benadryl). Clarinex (desloratadine) isn't over the counter (OTC), but instead is only available by prescription.
Seasonal or year-round allergy symptoms (runny nose, itchy nose, itchy or watery eyes)
Long-term hives - some oral tablets only
Clarinex (desloratadine) is an antihistamine. It blocks histamine, a natural chemical in your body that can cause allergy symptoms, like itchy eyes, runny nose, sneezing, and hives. By blocking histamine, Clarinex (desloratadine) helps relieve allergy symptoms.
Source: DailyMed
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Rare
Anaphylaxis, such as, cough, difficulty swallowing, dizziness, fast heartbeat, hives, itching, puffiness or swelling of eyelids or around the eyes or face or lips or tongue, shortness of breath, skin rash, tightness in chest, unusual tiredness or weakness, wheezing
dyspnea, such as, shortness of breath, difficult or labored breathing, tightness in chest, wheezing
edema, such as, swelling
pruritus, such as, itching skin
rash
tachycardia, such as, fast, pounding, or irregular heartbeat or pulse
urticaria, such as, hives or welts, itching, redness of skin, skin rash.
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
More common
Headache
Less common
Dizziness
dysmenorrhea, such as, difficult or painful menstruation
dyspepsia, such as, acid or sour stomach, belching, heartburn, indigestion, stomach discomfort , upset or pain,
fatigue, such as, unusual tiredness or weakness
myalgia, such as, joint pain, swollen joints, muscle aching or cramping, muscle pains or stiffness, difficulty in moving
pharyngitis, such as, body aches or pain, congestion, cough, dryness or soreness of throat, fever, hoarseness, runny nose, tender swollen glands in neck, trouble in swallowing, voice changes.
somnolence, such as, sleepiness or unusual drowsiness
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
First-choice option for allergies
Unlikely to cause sleepiness
Only need to take once a day
Available as a tablet and orally disintegrating tablet (ODT)
Available by prescription only
Might need a lower dose if you have liver or kidney problems because of risk of side effects
Tablets aren't approved for use for children younger than 12 years old
ODTs aren't approved for use for children younger than 6 years old
Take Clarinex (desloratadine) with or without food.
Instructions for the orally disintegrating tablet (ODT): Right after you take the tablet out of the blister packaging, place it on your tongue. Let it dissolve in your mouth before swallowing. You can take it with or without water.
While Clarinex (desloratadine) typically causes less drowsiness than other antihistamines, it's possible to still feel a little sleepy while taking this medication.
Avoid drinking alcohol while taking Clarinex (desloratadine). This combination can raise your risk of feeling sleepy or dizzy.
Don't start any new medications, especially other antihistamines, while you're taking Clarinex (desloratadine) without talking to your provider or pharmacist first. Taking more than one antihistamine medication can raise your risk of accidentally taking too much (overdose). This could lead to serious and sometimes life-threatening side effects, including extreme sleepiness, seizures, and hallucinations (seeing things that aren't real).
Clarinex (desloratadine) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Risk factors: Allergy to loratadine (Claritin)
Serious allergic reactions to Clarinex (desloratadine) are possible, including life-threatening problems like anaphylaxis (closing of the throat). Let your provider know if you have an allergy to loratadine (Claritin) since it's chemically similar to Clarinex (desloratadine). If you notice hives, a rash, swelling of the lips or tongue, or difficulty breathing after using Clarinex (desloratadine), get medical help right away.
The orally disintegrating tablets (ODTs) contain phenylalanine, a component of the artificial sweetener aspartame. If you have a genetic condition called phenylketonuria (PKU), taking the ODT formulation of Clarinex (desloratadine) can be dangerous for you. Make sure to tell your provider and pharmacist about your full medical history before taking Clarinex (desloratadine). Ask your pharmacist if you're not sure whether the formulation of Clarinex (desloratadine) that you're prescribed is safe for you. There are other formulations of the medication that might be safer for you.
| Dosage | Quantity | Price as low as | Price per unit | 
|---|---|---|---|
| 5mg | 30 tablets | $22.24 | $0.74 | 
Using this medicine with any of the following medicines is usually not recommended, but may be required in some cases. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
Allergy to loratadine (Claritin) or Clarinex (desloratadine)
Seasonal or year-round allergy symptoms (runny nose, itchy nose, itchy or watery eyes)
Long-term hives - some oral tablets only
Short-term relief of allergy symptoms (sneezing, runny nose, itchy or watery eyes, itching of the nose or throat)
Relief of itchiness due to chronic (long-term) hives in children ages 6 months to under 6 years old - certain liquid solutions only
Short-term relief of allergy symptoms (runny nose, itchy nose, itchy or watery eyes)
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