Desloratadine

About Desloratadine

Desloratadine is a long-acting antihistamine that blocks H1 histamine receptors, the receptors behind sneezing, a runny or itchy nose, itchy watery eyes and hives; it is a major metabolite of loratadine. The Clarinex label approves it for seasonal allergic rhinitis from age 2, and for perennial (year-round) allergic rhinitis and chronic idiopathic urticaria from 6 months, though those younger ages were covered by the oral solution and RediTabs that are now discontinued. The tablets in pharmacies today are for adults and adolescents 12 and older, at one 5 mg tablet once a day. Adults with liver or kidney impairment start with one tablet every other day. The label says higher doses or more frequent dosing add no benefit, and drowsiness was seen at 10 mg and 20 mg a day.

There is no boxed warning. The one warning on the label is hypersensitivity: rash, itching, hives, swelling and anaphylaxis have been reported, and the drug is stopped if they occur. It must not be taken by anyone allergic to desloratadine, any tablet ingredient, or loratadine. In adult allergy studies the common side effects were sore throat, dry mouth, muscle pain, tiredness, sleepiness and painful periods; MedlinePlus also lists headache, nausea, diarrhea and dizziness. Swelling of the face, throat, tongue or lips, or trouble breathing or swallowing, needs urgent care.

The current Clarinex label (revised August 2026) lists only the 5 mg film-coated tablet; it states that the RediTabs and oral solution are no longer marketed, and the Orange Book listings shown on Drugs.com mark them discontinued with no generic. Clarinex-D 12 Hour, which adds the decongestant pseudoephedrine, is a separate brand product for adults and adolescents 12 and older; it is swallowed whole twice a day and has its own contraindications, including narrow-angle glaucoma, urinary retention, MAO inhibitors and severe high blood pressure or coronary artery disease. Clarinex-D 24 Hour has been discontinued. Human data in pregnancy are insufficient, desloratadine passes into breast milk, and studies did not include enough people aged 65 and over to tell whether they respond differently.

Taking Desloratadine

How to take it

One 5 mg tablet once a day, at about the same time each day, with or without food. Do not take more, or more often, than prescribed. Swallow Clarinex-D 12 Hour tablets whole, without breaking, chewing or crushing them.

If you miss a dose

Take it when you remember, unless it is almost time for the next dose; then skip the missed dose. Do not take a double dose.

Storage

At room temperature in the original tightly closed container, away from light, heat and moisture (not in the bathroom), out of reach of children. Do not flush unwanted tablets; use a take-back program.

Interactions to know about

Ketoconazole, erythromycin, azithromycin, fluoxetine and cimetidine raised desloratadine levels in studies without a clinically relevant change in safety. Tell the prescriber about other cold or allergy medicines, and never take Clarinex-D 12 Hour with, or within 14 days of, an MAO inhibitor.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Desloratadine differs from pharmacy to pharmacy

Desloratadine 5 mg tablets are an older generic with more than one approved maker, but not every pharmacy keeps them on the shelf or on a flat-price generic list. Package sizes differ by maker (for example, bottles of 100 or 500), and a pharmacy that orders a bottle in for one prescription may quote it as a slow-moving item. A thirty-day supply of a once-daily tablet is a small fill, so the dispensing fee is a large part of the quote.

A prescription that names Clarinex and blocks substitution is filled with the brand, which is priced as a brand. Clarinex-D 12 Hour has no generic and is not rated equivalent to plain desloratadine, so it cannot be swapped at the counter; it is a brand-only product that fewer pharmacies stock.

Ways to pay less for Desloratadine without insurance

• Ask for generic substitution if the prescription is written for Clarinex; the generic 5 mg tablets are rated equivalent.
• For year-round allergies or chronic hives, ask the prescriber whether a ninety-day supply is possible, so you pay fewer dispensing fees.
• Ask whether desloratadine is on the pharmacy’s flat-price generic list, and compare more than one pharmacy.
• If you take Clarinex-D 12 Hour, ask the prescriber whether plain desloratadine would suit you, and ask the maker whether any savings or patient assistance program applies to someone paying cash.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Desloratadine

1. 1.Can I take my desloratadine with the over-the-counter allergy or cold medicines I already use?
2. 2.My kidneys or liver are not working fully; should I be taking my tablet every other day?
3. 3.Is the generic you stock rated equivalent to my Clarinex prescription?
4. 4.My Clarinex-D 12 Hour contains pseudoephedrine; is it safe with my blood pressure medicines?

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