Natural Health Research

Naturopathic Medicine
Health Quizzes
Cetirizine, Zyrtec


Cetirizine is a second-generation H1-receptor antagonist antihistamine used for the treatment of allergies, hay fever, angioedema, and hives.


Antihistamine, H2-receptor antagonist


allergic rhinitis, asthma, atopic dermatitis, urticaria,

Side Effects

drowsiness, fatigue, headache, xerostomia (dry mouth)

Drug-Vitamin-Herb Interactions

Negative interactions:

Magnesium (often found in antacids) may reduce the absorption of H2 antagonists. Take at a different time of day.

Positive interactions:

Folate absorption is best in an acidic environment. H2 antagonists reduce stomach acid which can lower folate absorption.

Vitamin B12
Vitamin B12 absorption may be impaired by H2 antagonists, which reduce stomach acid.

Iron and Zinc
Iron and Zinc absorption is inhibited by reduced stomach acid levels.




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