Cyclizine

Cyclizine structure

Cyclizine and chlorcyclizine are first generation antihistamines that are used largely to treat or prevent motion sickness and nausea.

Liver safety of Cyclizine

Cyclizine has been linked to very rare instances of clinically apparent acute liver injury.

Mechanism of action of Cyclizine

Cyclizine (sye' kli zeen) and chlorcyclizine (klor sye' kli zeen) are first generation antihistamines and antiemetics that belong to the piperazine class of these agents (with hydroxyzine and meclizine). Cyclizine and chlorcyclizine are most commonly used to treat the symptoms of nausea, vomiting and dizziness associated with motion sickness. However, they are also used to review symptoms of allergic rhinitis and the common cold, particularly in combination with sympathomimetic agents such as phenylephrine.

FDA approval information for Cyclizine

Cyclizine was first approved for use in the United States in 1966. It is still widely used and is available as tablets or capsules of 25 mg in multiple generic forms and under the trade name Cyclivert and Bonine in both prescription and nonprescription forms.

Dosage and administration for Cyclizine

The typical dose is 1 or 2 tablets one hour before travel. Chlorcyclizine is used in a similar dose regimen. Both cyclizine and chlorcyclizine are also available as chewable tablets and in oral liquid formulations as well as combinations with sympathomimetic agents (pseudoephedrine) for the treatment of symptoms of the common cold and nasal congestion.

Side effects of Cyclizine

Common side effects include sedation, impairment of motor function, confusion, dizziness, blurred vision, dry mouth and throat, palpitations, tachycardia, abdominal distress, constipation and headache. Antihistamines can worsen urinary retention and glaucoma.

• Dailymed label info on Cyclizine
• FDA Cyclizine

First Generation Antihistamines

• Brompheniramine
• Carbinoxamine
• Chlorcyclizine
• Chlorpheniramine
• Clemastine
• Cyclizine
• Cyproheptadine
• Dexbrompheniramine
• Dexchlorpheniramine
• Dimenhydrinate
• Diphenhydramine
• Doxylamine
• Hydroxyzine
• Meclizine
• Phenyltoloxamine
• Promethazine
• Triprolidine

Second Generation Antihistamines

• Acrivastine
• Cetirizine
• Fexofenadine
• Levocetirizine
• Loratadine
• Desloratadine