API Chlorpheniramine maleate

Chlorpheniramine maleate More Info

1. General Product Overview

Product Name: Chlorpheniramine Maleate

Common Brand Names: Often marketed as "Chlorpheniramine Maleate" or "Pyrilamine Maleate" .

CAS Number: 113-92-8

Molecular Formula: C₁₆H₁₉ClN₂·C₄H₄O₄ (or often represented as C₁₆H₁₉ClN₂O₂·C₄H₄O₄)

Molecular Weight: 390.86 g/mol

Physical Appearance: White to off-white crystalline powder or tablets. The raw material is typically a fine powder, while the final dosage form is often a white tablet.

Solubility: Easily soluble in water and ethanol; slightly soluble in chloroform and ether.

Purity: Typically ≥ 98% - 99% (as per pharmaceutical standards).

2. Pharmacological Profile

Mechanism of Action:

Chlorpheniramine Maleate is a potent H1 histamine receptor antagonist with additional anticholinergic activity. By blocking H1 receptors, it reduces capillary dilation and permeability, which helps alleviate symptoms of allergic reactions. It also exhibits a mild sedative effect due to its central nervous system activity.

Therapeutic Effects:

Antihistamine: Provides symptomatic relief from allergic reactions such as itching, swelling, and redness.

Anticholinergic: Contributes to the drying of secretions, which can be beneficial in treating rhinitis.

Bronchial Relaxant: Offers mild relief from bronchial spasms, making it useful in certain asthma or bronchitis cases.

3. Clinical Indications

Chlorpheniramine Maleate is indicated for the treatment and prevention of various allergic conditions, including but not limited to:

Allergic Rhinitis: Relief from nasal discharge, sneezing, and watery eyes.

Urticaria (Hives): Alleviates itching and rash.

Dermatitis: Effective for allergic dermatitis, including contact dermatitis and atopic eczema.

Common Cold: Often used in combination with other agents to relieve cold symptoms (e.g., sneezing, runny nose).

Motion Sickness: Prevents and treats nausea and vomiting associated with motion sickness.

Bronchial Conditions: Used as an adjunct in treating bronchial asthma and bronchitis due to its bronchodilatory properties.

4. Dosage and Administration

Standard Adult Dosage:

Tablets (e.g., 4 mg per tablet): Typically 1 tablet taken orally three times daily (every 4-6 hours) as needed.

Maximum Daily Dose: Generally should not exceed 12 mg per day for adults unless directed by a healthcare professional.

Pediatric Dosage:

Use with caution in children. The dosage for children is usually lower and must be determined by a pediatrician based on the child’s weight and age.

Special Considerations:

Onset of Action: The medication usually begins to work within 30 minutes to 1 hour after oral administration.

Duration: The therapeutic effect typically lasts for 4-6 hours, which is why it is often taken multiple times a day.

5. Safety, Side Effects, and Precautions

Common Adverse Reactions:

Drowsiness/Sedation: The most frequent side effect due to its antihistaminic and anticholinergic properties.

Dry Mouth/Thirst: Resulting from anticholinergic activity.

Dizziness, Fatigue, Weakness: Occasionally reported, especially in higher doses.

Gastrointestinal Disturbances: Nausea or mild stomach upset may occur.

Contraindications & Precautions:

Pregnancy & Lactation: Use only if clearly needed and prescribed by a doctor, as it can cross the placenta and may be excreted in breast milk.

Glaucoma, Enlarged Prostate, Urinary Retention: Use with caution due to anticholinergic effects that can exacerbate these conditions.

Drug Interactions: Avoid concurrent use with other antihistamines (e.g., diphenhydramine) or MAO inhibitors without medical advice.

Storage Conditions:

Store at room temperature (2-8°C for some raw materials), in a dry, well-ventilated place away from direct sunlight and moisture.

6. Regulatory and Quality Standards

Chlorpheniramine Maleate products are typically manufactured in compliance with international pharmacopeial standards such as British Pharmacopoeia (BP), United States Pharmacopeia (USP), and Chinese Pharmacopoeia (CP). These standards ensure the product meets strict criteria for purity, potency, and safety.