What is loratadine, and how does it work (mechanism of action)?
Loratadine is a long-acting, non-sedating
antihistamine that is used for the treatment of
allergies. Histamine
is a chemical that causes many of the signs and symptoms of an allergy. Histamine
is released from histamine-storing cells (mast cells) and attaches to other
cells that have receptors for histamine on their surfaces. Histamine stimulates
the cells to release chemicals that produce effects that we associate with
allergy, including welts, itching, and tissue swelling. Loratadine blocks one
type of histamine receptor (the H1 receptor) and thus prevents activation of
cells with H1 receptors by histamine. Unlike some antihistamines, loratadine
does not enter the brain from the blood and, therefore, does not cause
drowsiness when taken at recommended doses. The FDA approved loratadine in April
1993.
What brand names are available for loratadine?
Claritin, Claritin RediTabs, Alavert, Claritin Hives Relief,
Children's Claritin, and others
Is loratadine available as a generic drug?
GENERIC AVAILABLE: Yes
Do I need a prescription for loratadine?
No
What are the uses for loratadine?
- Loratadine is used for the relief of nasal and non-nasal
symptoms of seasonal
hay fever (allergic rhinitis). - It is also used to treat patients with
chronic welts (urticaria) and
allergic skin rash.
What are the side effects of loratadine?
The most common adverse events with loratadine are:
Nervousness and difficulty sleeping have also been reported.
What is the dosage for loratadine?
The usual dose of loratadine is 10 mg daily for adults and children
older than six years of age. The dose for children 2 to 6 years of age is 5 mg
daily.
Which drugs or supplements interact with loratadine?
:
Erythromycin,
cimetidine (Tagamet),
and ketoconazole
(Nizoral) increase the blood concentration of loratadine by inhibiting the
elimination of loratadine. This may result in increased adverse events from
loratadine.
St. John’s wort,
carbamazepine
(Tegretol, Tegretol XR , Equetro, Carbatrol, Epitol, Teril), and rifampin reduce blood levels of
loratadine.
QUESTION
Allergies can best be described as:
See Answer
Is loratadine safe to take if I’m pregnant or breastfeeding?
Loratadine is secreted in breast milk at levels similar to
blood levels. Nursing mothers should decide whether to stop
breastfeeding
or discontinue loratadine.
What else should I know about loratadine?
What preparations of loratadine are available?
- Tablets: 10 mg.
- Tablets, disintegrating: 5 and 10 mg.
- Tablets,
chewable: 5 mg. - Syrup: 5 mg/5 ml.
How should I keep loratadine stored?
Tablets should be stored between 2 C and 30 C (36 F and 86 F), and
syrup should be stored between 2 C and 25 C (36 and 77 F).