Istamex (Chlorphenamine Maleate)

Chlorphenamine maleate, the active ingredient in Istamex, is a first‑generation antihistamine presented as an unspecified strength/oral tablet for oral use. It relieves symptoms of allergic rhinitis, urticaria, seasonal allergies and common cold in adults and children. GNH USA supplies Istamex as a licensed, GDP‑compliant international pharmaceutical supplier serving hospitals, pharmacies and clinics worldwide.

Istamex is a first‑generation H1‑antagonist used to manage allergic and cold‑related conditions. - Allergic rhinitis: reduces sneezing, itching and nasal discharge. - Urticaria (hives): alleviates skin itching and wheal formation. - Seasonal allergies: controls hay‑fever symptoms such as watery eyes and runny nose. - Common cold symptom relief: eases nasal congestion, sneezing and watery eyes.

Adverse reactions may occur with chlorphenamine use.

Common Side Effects: - Drowsiness: mild to moderate sedation. - Dry mouth: reduced salivation. - Blurred vision: transient visual disturbance. - Constipation: slowed gastrointestinal motility. - Urinary retention: difficulty emptying the bladder. - Headache: mild cranial discomfort.

Serious or Rare Side Effects: - Anaphylaxis: severe allergic reaction with airway compromise. - Cardiac arrhythmia: irregular heart rhythm, especially in predisposed patients. - Seizures: rare central nervous system excitation. - Blood dyscrasias: agranulocytosis or thrombocytopenia. - Hepatic injury: elevated liver enzymes or hepatitis. - Stevens‑Johnson syndrome: severe skin and mucous membrane reaction.

Before using Istamex, consider the following safety measures. - Avoid driving or operating machinery: may cause drowsiness. - Use caution in patients with glaucoma: anticholinergic effects can increase intra‑ocular pressure. - Monitor elderly patients: heightened sensitivity to sedation and anticholinergic load. - Review concomitant CNS depressants: additive sedative effect possible. - Store below 25°C: keep in the original pack, protect from moisture.

Chlorphenamine can interact with several drug classes.

Major Interactions (Avoid): - Monoamine oxidase inhibitors (MAOIs): risk of hypertensive crisis. - Alcohol and other central nervous system depressants: enhanced sedation. - Other antihistamines or anticholinergics: cumulative anticholinergic burden.

Moderate Interactions (Monitor Closely): - Antihypertensive agents: possible additive hypotensive effect. - Selective serotonin reuptake inhibitors (SSRIs): may increase serotonergic activity. - Theophylline: potential for increased theophylline toxicity.