The maximum recommended dose of Claritin (loratadine) is one 10 mg tablet per day for adults and children 6 and older. Taking more than one tablet in 24 hours won’t improve your allergy relief, and it increases the risk of side effects.
Standard Daily Dose for Adults and Children
Claritin comes in regular tablets, chewable tablets, and orally disintegrating tablets, but the dosing is the same across all forms: 10 mg once a day. That’s one tablet, once, and then you wait a full 24 hours before taking the next one.
For children ages 2 to 5, the typical dose is 5 mg per day, usually given as a liquid syrup or half a chewable tablet. Children 6 and older follow the same 10 mg dose as adults.
Why Doubling Up Doesn’t Help
If your allergies are still bothering you after taking Claritin, it’s tempting to reach for a second tablet. But loratadine works by blocking histamine receptors, and one dose already occupies most of those receptors for a full 24-hour cycle. A second tablet doesn’t meaningfully increase the antihistamine effect. It just raises the drug level in your blood without adding benefit.
If Claritin at the standard dose isn’t controlling your symptoms, the better move is switching to a different antihistamine (like cetirizine or fexofenadine) or adding a nasal corticosteroid spray, not doubling your Claritin dose.
What Happens If You Take Too Much
Taking more loratadine than recommended can cause a rapid heart rate, headache, drowsiness, and dizziness. In larger amounts, it may lead to confusion, agitation, or drops in blood pressure. Loratadine is considered safer in overdose than older antihistamines like diphenhydramine (Benadryl), but that doesn’t mean extra doses are harmless.
If you accidentally took two tablets in one day, serious harm is unlikely for most adults. Monitor for unusual drowsiness or a racing heartbeat and contact Poison Control (1-800-222-1222) if you’re concerned.
Claritin-D Has Different Limits
Claritin-D is not the same product as regular Claritin. It combines loratadine with pseudoephedrine, a decongestant, and the dosing rules are stricter because pseudoephedrine affects your heart rate and blood pressure.
The 12-hour version of Claritin-D contains 5 mg of loratadine and 120 mg of pseudoephedrine per tablet. You can take one tablet every 12 hours, up to two tablets in 24 hours. The 24-hour version contains 10 mg of loratadine and 240 mg of pseudoephedrine, and the limit is one tablet per day.
The pseudoephedrine component makes Claritin-D riskier for people with high blood pressure, heart disease, thyroid problems, diabetes, or an enlarged prostate. If any of those apply to you, regular Claritin (without the “D”) is the safer choice.
Kidney or Liver Problems Change the Dose
Your liver and kidneys are responsible for clearing loratadine from your body. If either organ isn’t working well, the drug builds up faster and stays in your system longer. People with significant kidney impairment or liver disease should take 10 mg every other day instead of every day. For children ages 2 to 6 with these conditions, the adjusted dose is 5 mg every other day.
Medications That Interact With Claritin
Loratadine has relatively few drug interactions compared to other antihistamines, but a handful of medications can raise loratadine levels in your blood. These include erythromycin (an antibiotic), cimetidine (used for heartburn), and amiodarone (a heart rhythm medication). If you take any of these, loratadine may have a stronger effect than expected at the normal dose.
Any medication that causes drowsiness, dry mouth, or difficulty urinating can see those side effects worsen when combined with loratadine. This includes sleep aids, certain antidepressants, and muscle relaxants.