Desloratadine
Pronunciation: pronunciation varies by local usage.
- Generic name
- desloratadine
- Brand names
- Clarinex (United States), Neoclarityn (United Kingdom)
- Drug class
- Second-generation (non-sedating) antihistamine
- Form
- Tablet, orally disintegrating tablet, or oral solution, depending on country and age
- Route
- Oral
- Legal status
- Availability and prescription status differ by country and product; this page does not confirm OTC status in any specific country.
Availability and supply rules vary by country
Trade names by country: United States · United Kingdom · Canada
Australia: · Full directory
What desloratadine is and how it works
Desloratadine is a second-generation, non-sedating antihistamine that blocks histamine to relieve allergy symptoms. (1) (2)
It is used for seasonal and perennial allergic rhinitis and for chronic hives (chronic idiopathic urticaria). Approved age ranges differ between countries.
Mechanism of action: how desloratadine works
Desloratadine is the major active metabolite of loratadine, a long-acting tricyclic histamine antagonist with selective H1-receptor antagonist activity. The US label reports an elimination half-life of approximately 27 hours in adults (approximately 33.7 hours in elderly patients) and a mean time to maximum plasma concentration (Tmax) of approximately 3 hours post-dose. (1) (2)
What desloratadine is used for
Allergic rhinitis (United States)
Relieves nasal and non-nasal symptoms of seasonal allergic rhinitis in patients 2 years and older, and of perennial allergic rhinitis in patients 6 months and older, per the current US label. (1)
Chronic idiopathic urticaria (United States)
Relieves the symptoms of chronic hives of unknown cause in patients 6 months and older, per the current US label. (1)
Allergic rhinitis and urticaria (United Kingdom)
Relieves symptoms of allergic rhinitis and urticaria in adults and adolescents 12 years and older; the UK product reviewed is not suitable for children under 12. (2)
Before taking desloratadine
Do not take / not appropriate for
- Do not take desloratadine if you are allergic to desloratadine, loratadine, or any ingredient of the specific product. (all products) (1) (2)
Tell your clinician about
- Kidney or liver problems — your prescriber may need to adjust your dose depending on your country's product information.
- A personal or family history of seizures, as this UK product's information recommends caution in this group.
- Pregnancy or breastfeeding.
- Every other medicine you take.
How to take desloratadine
- Take exactly as directed for your age and the specific product.
- Tablets are usually taken once daily, with or without food.
- Do not change your dose or how often you take it without checking with your prescriber or pharmacist.
Procedures and treatment changes
Tell the treating team before surgery, procedures, or any medicine change. Do not alter treatment without the responsible clinician. (1)
Missed dose
Take the missed dose as soon as you remember and continue your regular schedule. Do not take a double dose to make up for a missed one. If you are unsure, ask your pharmacist or prescriber.
Overdose
Contact your healthcare provider, pharmacist, or a poison-control/emergency service promptly if an overdose is suspected, even though serious complications are considered unlikely. (2)
Side effects
Desloratadine is generally well tolerated and is considered non-sedating, though some people still report tiredness.
Fatigue, dry mouth, or headache
What to notice: These are the most commonly reported effects.
What to do: Tell your prescriber or pharmacist if these are severe or persistent. (2) (1)
Sore throat, muscle pain, or drowsiness
What to notice: Reported in US clinical trials.
What to do: Discuss persistent symptoms with your prescriber. (1)
Nausea and vomiting
Incidence: Common
Headache
Incidence: Common
Signs of an allergic reaction
What to notice: Rash, itching, hives, swelling, or difficulty breathing.
What to do: Contact your prescriber promptly for non-severe symptoms; seek emergency care for severe breathing difficulty or swelling. (1)
Serious warnings
Hypersensitivity reaction / anaphylaxis — emergency
Symptoms: Rash, itching, hives, swelling, difficulty breathing, or irregular heartbeat.
Action: Seek emergency medical help immediately; a clinician or emergency service will decide whether desloratadine needs to be stopped. (1) (2)
Liver function changes —
Action: Seek immediate medical attention if signs of allergic reaction or liver problems occur. Contact your healthcare provider before stopping treatment.
Interactions
| Medicine or test | Effect | Action |
|---|---|---|
| Ketoconazole, erythromycin, azithromycin, fluoxetine, or cimetidine | These can increase desloratadine blood levels. The manufacturer's studies reported no clinically relevant change in the safety profile at increased levels. | Tell your prescriber and pharmacist about all medicines you take before combining. (1) |
Pregnancy, breastfeeding, kidney/liver function, age
Kidney or liver impairment
The US label describes a reduced dose (5 mg every other day) for adults with kidney or liver impairment. The UK product advises caution in severe kidney impairment. Follow your prescriber's exact instructions. (1) (2)
Seizure history
The UK product information recommends caution in people with a personal or family history of seizures. (2)
Pregnancy and breastfeeding
Available human pregnancy data are limited. Desloratadine passes into breast milk; discuss the balance of benefits and risks with your prescriber. (1)
Children
Age eligibility differs by country and product: the US label covers ages from 6 months for perennial rhinitis and urticaria, and from 2 years for seasonal rhinitis, using age-specific oral-solution doses; the UK product reviewed is for ages 12 and over only. Do not apply one country's paediatric dosing to another. (1) (2)
Monitoring
Before starting
- Confirm age, indication, and country-specific product before selecting a dose.
- Screen for kidney or liver impairment and a personal or family history of seizures.
During treatment
- Watch for signs of allergic reaction.
Storage
United States (Clarinex): store at 25C (77F), with excursions permitted between 15C and 30C (59F to 86F); this product is heat-sensitive, so avoid exposure at or above 30C (86F). United Kingdom (Neoclarityn): do not store above 30C, and keep in the original package. Keep out of reach of children.
Study the drug class: Antihistamines
Professional information
Clinician-facing context only. Use the current local product information for exact age- and impairment-based dosing.
United States
Indication: Allergic rhinitis and chronic idiopathic urticaria
Dose summary: Adults and adolescents 12+: 5 mg once daily (seasonal allergic rhinitis, perennial allergic rhinitis, or chronic idiopathic urticaria). Children 6-11 years: 2.5 mg once daily (same three indications). Children 12 months-5 years: 1.25 mg once daily oral solution (perennial allergic rhinitis or chronic idiopathic urticaria; seasonal allergic rhinitis is approved from age 2 years, not from 12 months). Children 6-11 months: 1 mg once daily oral solution (perennial allergic rhinitis only).
Renal context: Hepatic or renal impairment: reduce to one 5 mg tablet every other day in adults. (1)
United Kingdom
Indication: Allergic rhinitis and urticaria
Dose summary: Adults and adolescents 12+: one 5 mg tablet once daily. Not indicated for children under 12 in the product reviewed.
Renal context: Use with caution in severe renal insufficiency; use current local product information. (2)
Hepatic guidance
Reduce adult dose to 5 mg every other day in hepatic impairment, per the US label.
Overdose note
Serious complications from overdose are considered unlikely per the UK patient leaflet; manage supportively with poison-centre or specialist advice as needed. (1) (2)
Frequently asked questions
What is desloratadine used for?
desloratadine is prescribed for approved indications. Always follow your healthcare provider's guidance.
What are the side effects of desloratadine?
Common side effects may include gastrointestinal symptoms and headache. Serious side effects require immediate medical attention.
Can I take desloratadine with other medications?
Always inform your healthcare provider about all medications you are taking, including over-the-counter products and supplements.
What is the mechanism of action of desloratadine?
Desloratadine is the major active metabolite of loratadine, a long-acting tricyclic histamine antagonist with selective H1-receptor antagonist activity. The US label reports an elimination half-life of approximately 27 hours in adults (approximately 33.7 hours in elderly patients) and a mean time to maximum plasma concentration (Tmax) of approximately 3 hours post-dose. (1) (2)
References
- CLARINEX (desloratadine) tablet, film coated — prescribing informationDailyMed, U.S. National Library of Medicine (FDA-approved label) · United States · accessed 2026-07-26 · source 1
- Neoclarityn 5 mg film-coated tablets — Patient Information Leafletelectronic Medicines Compendium (UK) · United Kingdom · accessed 2026-07-26 · source 2
- DESLORATADINE TABLET, FILM COATED [LUPIN PHARMACEUTICALS, INC.] — US prescribing information (DailyMed SPL)U.S. National Library of Medicine (DailyMed) · US · accessed 2026-08-14 · source 3
- Desloratadine — patient drug information (MedlinePlus)U.S. National Library of Medicine (MedlinePlus) · US · accessed 2026-08-14 · source 4
- Desloratadine — FDA approval record (Drugs@FDA ANDA078355)U.S. Food and Drug Administration · US · accessed 2026-08-14 · source 5
- desloratadine — RxNorm normalized drug concept (RXCUI 275635)U.S. National Library of Medicine (RxNorm) · US · accessed 2026-08-14 · source 6
Brand names by country
Single-ingredient desloratadine names are shown separately by country. Product availability, strengths, and supply rules can change; combination products are not included here.
Priority countries
United States
- Clarinex5 mg · organon llc
United Kingdom
- Neoclarityn (2)verified
Canada
- DESLORATADINE ALLERGY
- AERIUS
- AERIUS KIDS
- ALLERNIX MULTI SYMPTOM