Cyclizine is an antihistamine and antiemetic pharmaceutical active ingredient used primarily for the prevention and treatment of nausea, vomiting and motion sickness. It belongs to the piperazine class of antihistamines and has both antihistaminic and antiemetic properties.
Cyclizine is a first-generation H1 antihistamine that acts on histamine H1 receptors and also produces antiemetic effects through activity within the central nervous system. It is available in pharmaceutical formulations as cyclizine hydrochloride.
Cyclizine is identified by CAS No. 82-92-8. It has the molecular formula C18H22N2 and a molecular weight of 266.39 g/mol.
Cyclizine primarily acts as an H1 histamine receptor antagonist. Its antihistaminic activity helps reduce stimulation of pathways involved in nausea and vomiting. Cyclizine also has anticholinergic properties that contribute to its antiemetic effects.
Cyclizine is used for the prevention and treatment of motion sickness, nausea and vomiting associated with various conditions. The specific approved indications depend on the dosage form and applicable regulatory requirements.
Cyclizine can be supplied for pharmaceutical formulation, development and manufacturing applications, subject to applicable quality and regulatory requirements.
Quality evaluation may include identification, assay, related substances, loss on drying, residue on ignition, pH, melting point, water content and other applicable pharmaceutical quality attributes.
Final acceptance criteria should always be based on the approved product specification, validated analytical methods and batch-specific Certificate of Analysis (CoA).
| Parameter | Specification |
|---|---|
| Appearance | White to off-white crystalline powder |
| Identification | Conforms to Cyclizine identity by validated analytical methods |
| Assay (HPLC) | NLT 98.0% by HPLC |
| Loss on Drying | NMT 1.0% |
| Residue on Ignition | NMT 0.5% |
| Heavy Metals | NMT 10 ppm |
| pH (1% Solution) | 2.0 – 4.0 |
| Individual Impurity | NMT 1.0% |
| Total Impurities | NMT 2.0% |
| Water Content | NMT 1.0% |
| Melting Point | 150°C – 154°C |