Levocetirizine dihydrochloride
[CAS# 130018-87-0]

Identification

• Classification: API >> Antiallergic >> Antihistamine
• Name: Levocetirizine dihydrochloride
• Synonyms: [2-[4-[(R)-(4-Chlorophenyl)phenylmethyl]-1-piperazinyl]ethoxy]-acetic acid dihydrochloride
• Molecular Formula: C₂₁H₂₅ClN₂O₃.2(HCl)
• Molecular Weight: 461.81
• CAS Registry Number: 130018-87-0
• EC Number: 641-093-3
• SMILES: C1CN(CCN1CCOCC(=O)O)[C@H](C2=CC=CC=C2)C3=CC=C(C=C3)Cl.Cl.Cl

Properties

• Melting point: 215-220 °C

Safety Data

• Hazard Symbols: GHS07;GHS09 Warning
• Risk Statements: H302-H400
• Safety Statements: P264-P270-P273-P301+P317-P330-P391-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute toxicity	Acute Tox.	4	H302
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Acute toxicity	Acute Tox.	4	H332
Skin corrosion	Skin Corr.	1B	H314
Acute toxicity	Acute Tox.	4	H312
Chronic hazardous to the aquatic environment	Aquatic Chronic	3	H412
Skin irritation	Skin Irrit.	2	H315
Carcinogenicity	Carc.	2	H351
Eye irritation	Eye Irrit.	2	H319

Discovery and Applications

Levocetirizine dihydrochloride, a second-generation antihistamine, was developed as an improved version of cetirizine to provide more effective relief from allergic symptoms with fewer side effects. Cetirizine, a widely used antihistamine, contains both levocetirizine and its mirror image, dextrocetirizine. Through careful research, scientists discovered that levocetirizine exhibited greater antihistaminic activity and fewer sedative effects compared to its dextrorotatory counterpart. This led to the development of levocetirizine dihydrochloride as a standalone medication for the treatment of allergic rhinitis, chronic urticaria, and other allergic conditions. The discovery of levocetirizine dihydrochloride marked a significant advancement in allergy treatment, offering patients a more effective and tolerable option for managing allergic symptoms.

Levocetirizine dihydrochloride is commonly prescribed for the relief of symptoms associated with allergic rhinitis, including sneezing, nasal congestion, itching, and rhinorrhea. Its rapid onset of action and long duration of effect make it particularly effective for controlling allergic rhinitis symptoms, both seasonally and perennially.

In the treatment of chronic urticaria, levocetirizine dihydrochloride helps alleviate itching and hives associated with this condition. Its non-sedating nature allows for daytime use without impairing cognitive function or causing drowsiness.

Levocetirizine dihydrochloride is also available in ophthalmic formulations for the management of allergic conjunctivitis. When administered as eye drops, it provides relief from itching, redness, and watering of the eyes caused by allergens such as pollen, dust, or pet dander.

The safety and efficacy of levocetirizine dihydrochloride have been established in pediatric populations, making it a preferred choice for children aged six months and older suffering from allergic rhinitis or chronic urticaria. Pediatric formulations ensure accurate dosing and safe administration in children.

Levocetirizine dihydrochloride is effective in relieving pruritus (itching) associated with various dermatological conditions, such as atopic dermatitis, eczema, and insect bites. Its antihistaminic activity helps alleviate itching, allowing patients to experience relief and improve their quality of life.

Beyond its approved indications, levocetirizine dihydrochloride may be used off-label for the management of other allergic conditions, such as allergic asthma, food allergies, and drug hypersensitivity reactions. Its efficacy in these conditions may vary, and its use should be guided by healthcare professionals.

References

2024. Efficacy and safety of bilastine vs. levocetirizine for chronic idiopathic urticaria. Chinese Medical Journal, 137(7), 819-825.
DOI: 10.1097/cm9.0000000000003071

2023. Levocetirizine attenuates cyclophosphamide-induced lung injury. BMC Pharmacology and Toxicology, 24(1), 69.
DOI: 10.1186/s40360-023-00717-3

2024. Anti-edematous effects of epinastine, cetirizine and its enantiomers. Die Pharmazie, 79(6), 141-146.
DOI: 10.1691/ph.2024.4518