How long does it take for Claritin to work?

Claritin is a Brand name of Loratadine which was developed by Schering-Plough in 1981 and marketed not until 1993 when it was listed among the World Health Organization’s List of Essential Medicines.  It is basically used to fight Histamines “chemical” released into your body system as part of an allergic reaction. Such allergies include:-

  • allergic rhinitis (hay fever)
  • pollen
  • sneezing
  • watery eyes
  • itchy eyes, nose
  • flashing light headaches and ache

Claritin is a tricyclic antihistamine, which acts as a selective inverse agonist of peripheral histamine H1-receptors. When given orally, it absorbs well from the gastrointestinal tract.
Theoretically, Claritin’s peak effect occurs after one to two hours, and it’s biological half-life is on average 8 hours (range 3 to 20 hours). Forty Percent- 40% is excreted through urine and feces as conjugated metabolites.

However that is not the case when administered, Claritin shows to be a time-released medication, it builds up in the system gradually, effectively reaching a peak stable state in about 3 days – Lasting for about 1-2weeks in the system.

This is the period it takes the released histamines to degrade and disappear. While waiting patiently as Claritin (loratadine) effectively blocks the release of new histamines in your body system.
Sometimes it seems to have zero effect on patients. It is less proactive to other antihistamines such as Zyrtec work that works in less than an hour. Allegra (fexofenadine) reaches a peak effect within 2 hours and Zyrtec (cetirizine) reaches a peak effect in 1-2 hours.

Truth Be Told Claritin, Like All Other Anti-Histamines, Works Best When Taken As Precaution, Before Ever Experiencing Symptoms

Factors affecting the duration it takes Claritin (Loratadine) To Work


  1. Age: Claritin and the chewable tablets used on children younger than 6 years are less effective on severe allergies
  2. Type of Allergies: It is a fact that Claritin (Loratadine) is less effective on severe allergies e.g hives
  3. Dosage: This is based on the doctor’s prescription – Less “10mg or 20mg) you take can increase the time it takes for Claritin to work in your body system.
    tolerance effect This is where an antihistamine loses its effect after long-term use on a patient. Changing the antihistamine brand, in this case, may be effective.

How long does it take children Claritin (loratadine) to work?

For children, another antihistamine like zyrtec works best though a little sedating for some, because it takes Claritin about a week or 2 to be effective on them.

How Long Does It Take For Claritin To Work On Hives

This is to note that Claritin (Loratadine) is not a treatment for hives. It will take forever to treat does not prevent hives or prevent/treat a serious allergic reaction (e.g., anaphylaxis)

Top 2 Alternatives to Claritin (loratadine)


Claritin (loratadine) – antihistamine alternative is based on effectiveness and how long its effect takes place

  1. Zyrtec (cetirizine)
  2. Allegra (fexofenadine)

All Said It is always best to check with a pharmacist or your doctor first before administrating any form of medication. Do you have any experience with Claritin (Loratadine)?  How Long Does It Take For Claritin To Start Working and what kind of allergies did you have… let us hear you in the comment section below.

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