Loratadine is a once-daily non-sedating antihistamine, usually 10 mg. It treats hay fever, allergic rhinitis, itchy watery eyes, hives and allergic itching. It is the least sedating of the commonly used antihistamines, which makes it a good choice for daytime use.
What is Loratadine?
Loratadine is a second-generation antihistamine, dispensed as 10 mg tablets and as a syrup for children. In South Africa it is sold under its own name and as Clarityne, Lorano, Allergex Non-Drowsy and Pollentyme.
When the immune system reacts to something harmless — pollen, dust mite, mould, animal dander — mast cells release histamine. Histamine binding to H1 receptors produces sneezing, an itchy runny nose, watery eyes, and in the skin, weals and itching. Loratadine occupies those receptors so histamine cannot.
Its defining feature is how little it sedates. First-generation antihistamines such as the chlorphenamine in Rhineton cross freely into the brain and cause pronounced drowsiness. Loratadine barely crosses at all, and at standard amounts most people notice no sedation whatsoever — less even than with cetirizine, which sedates a minority.
That makes loratadine the usual recommendation for someone who needs allergy control while driving, studying, working, or operating machinery.
The trade-off is modest: cetirizine is somewhat more effective for itching and for hives. For nasal allergy symptoms the two perform similarly.
What is Loratadine commonly used for?
Loratadine is used for allergic conditions:
- Hay fever (seasonal allergic rhinitis) — sneezing, runny and itchy nose, itchy throat, watery eyes.
- Perennial allergic rhinitis, from dust mite, mould or pet dander.
- Allergic conjunctivitis — itchy, red, watery eyes.
- Chronic urticaria (hives).
- Itching from allergic skin conditions and insect bites.
- Mild allergic reactions.
For seasonal allergy, the most useful practical point is timing. An antihistamine blocks histamine from binding, but it does not reverse a reaction already under way. Starting it a week or two before your usual trigger season and taking it daily through the season — rather than only on bad days — gives noticeably better control than reacting to symptoms as they appear.
Two things it does not do:
It does not treat a cold. Cold symptoms are viral, not histamine-driven. It may slightly dry a runny nose but will not shorten the illness or relieve aches and fever.
It does not treat asthma, and is not a substitute for an inhaler.
For blocked nose specifically, antihistamines underperform. Congestion in allergic rhinitis is driven more by inflammation than by histamine, and a steroid nasal spray used consistently over one to two weeks works considerably better. Many people with persistent hay fever do best with the spray as the foundation and loratadine on top for sneezing and itching.
How Loratadine fits into this medicine category
| Group | Examples | Note |
|---|---|---|
| Second-generation antihistamines | Loratadine, cetirizine (Austell Cetirizine, Seasoneze), fexofenadine | Once daily; minimal drowsiness |
| First-generation antihistamines | Chlorphenamine (Rhineton), cyproheptadine (Cipla Actin) | Effective; markedly sedating |
| Steroid nasal sprays | Fluticasone, mometasone | Best for congestion; work over days |
| Decongestants | Pseudoephedrine, oxymetazoline | Short-term only; rebound with overuse |
| Eye drops | Sodium cromoglycate, antihistamine drops | Targeted relief for itchy eyes |
If loratadine is not controlling itching or hives well, cetirizine is often more effective — a simple switch worth asking a pharmacist about. See the allergy, cold and flu medicines hub.
What to check before using Loratadine
Take one tablet once daily, at any time, with or without food.
Do not take it with another antihistamine, including combination cold, flu and allergy products that contain one already.
Speak to a pharmacist or doctor if:
- You have liver disease. Loratadine is processed by the liver, and a reduced amount or alternate-day dosing may be appropriate — this matters more for loratadine than for cetirizine, which is cleared by the kidneys.
- You have kidney disease.
- You are pregnant or breastfeeding.
- The medicine is for a child. Syrups and lower strengths exist — check the right form and amount for their age and weight.
- You take ketoconazole, itraconazole or erythromycin, which raise loratadine levels.
- You are due allergy testing. Antihistamines suppress skin prick test results and usually must be stopped several days beforehand — tell whoever arranges the test.
Avoid alcohol until you know how it affects you, though the interaction is much less pronounced than with sedating antihistamines.
Follow the pack instructions. This page does not set doses.
Possible cautions and when to ask a pharmacist or doctor
Drowsiness is uncommon at standard amounts — that is the point of loratadine. It does become more likely if you exceed the recommended amount, which is one reason not to take extra when symptoms are bad. If more control is needed, ask rather than doubling up.
Headache, dry mouth and tiredness are the usual complaints, generally mild.
If it is not working, switch rather than escalating. Cetirizine is more effective for itching and hives in many people. Persistent symptoms despite a daily antihistamine can also mean congestion is the dominant problem, or that the trigger is not allergic at all.
Symptoms lasting beyond a few weeks warrant assessment rather than an indefinite over-the-counter routine — particularly if you need it year-round, which is worth investigating.
Reducing exposure helps and lowers how much medicine you need: dust mite covers on mattress and pillows, windows shut in the early morning and evening at high pollen times, showering and changing after being outdoors, drying laundry indoors during pollen season, and keeping pets out of bedrooms.
Do not use decongestant nasal sprays for more than a few days. They work well briefly then cause rebound congestion worse than the original — a common trap for someone whose nose stays blocked on an antihistamine.
Seek urgent medical attention for swelling of the face, lips, tongue or throat, difficulty breathing or swallowing, wheezing, faintness with a widespread rash, or a rash that blisters or peels. Hives accompanied by any swelling of the mouth or throat is an emergency, not an allergy inconvenience.
Related medicine guides
Frequently asked questions
What is loratadine 10 mg used for? Hay fever and allergic rhinitis, itchy watery eyes, hives and allergic itching.
Will it make me drowsy? Usually not. Loratadine is the least sedating of the commonly used antihistamines, which is why it suits daytime use.
How is it different from cetirizine? Both are once-daily and non-sedating. Cetirizine is somewhat more effective for itching and hives; loratadine sedates even less.
Can I take it for a cold? It will not treat a cold, which is viral rather than histamine-driven. It may slightly dry a runny nose.
Will it unblock my nose? Only partly. Congestion responds better to a steroid nasal spray used consistently over one to two weeks.
Can I take two if one is not enough? No — exceeding the recommended amount makes drowsiness more likely without reliably improving control. Ask a pharmacist about switching instead.