Chlorphenamine (Chlorpheniramine)

SCOPE: ORAL TABLETS ONLY. This record covers the oral route, which is this page's primary route - the page's own dose, route and paediatric fields all lead with oral. || THE PARENTERAL REGIMEN IS NOT SOURCED HERE AND IS NOT CARRIED. To restore a parenteral dose, fetch a chlorphenamine INJECTION SPC; the anaphylaxis-adjunct role belongs to resuscitation guidance and must be cited as such, never as SPC content. || ELDERLY, §4.2 verbatim: 'The elderly are more likely to experience neurological anticholinergic effects. Consideration should be given to using a lower daily dose (e.g. a maximum of 12mg in any 24 hours).' §4.4 adds: 'Avoid use in elderly patients with confusion.' This 12 mg elderly figure is deliberately kept out of maxDose so that the field carries one unambiguous adult ceiling. || DRIVING AND SEDATION, §4.4 verbatim: 'The anticholinergic properties of chlorphenamine may cause drowsiness, dizziness, blurred vision and psychomotor impairment in some patients which may seriously affect ability to drive and use machinery. The effects of alcohol may be increased and therefore concurrent use should be avoided.' || DO NOT DOUBLE UP, §4.4 verbatim: 'Should not be used with other antihistamine containing products, including antihistamine containing cough and cold medicines.' || EXCIPIENT, §4.4 verbatim: 'Patients with rare hereditary problems of galactose intolerance, Lapp lactase deficiency or glucose-galactose malabsorption should not take this medicine.' || INTERACTIONS, §4.5 verbatim: 'Chlorphenamine inhibits phenytoin metabolism and can lead to phenytoin toxicity.' Concurrent hypnotics or anxiolytics 'may cause an increase in sedative effects'. || The SPC gives one regimen for all its indications.

§4.2, verbatim and complete for children: 'Children aged 6 - 12 years: ½ tablet 4 to 6 hourly. Maximum daily dose: 3 tablets (12mg) in any 24 hours. Not recommended for children under the age of 6 years.' Half a tablet (the SPC writes it as the character ½) is 2 mg on the same arithmetic that pins the tablet at 4 mg (the SPC's own '3 tablets (12mg)'). || dosePerKg IS NULL AND MUST STAY NULL: this SPC doses chlorphenamine by AGE BAND and by fraction of a tablet, never by body weight - there is no per-kg figure anywhere in the bundle, so no weight calculator may run on it. || NOT RECOMMENDED UNDER 6 YEARS for this product. Any under-6 use, and any liquid or parenteral formulation, is outside this bundle entirely. || §4.4 warns, verbatim: 'Children and the elderly are more likely to experience the neurological anticholinergic effects and paradoxical excitation (eg. Increased energy, restlessness, nervousness).' || concentration IS NULL: this is a tablet, not a liquid, and no mg/mL figure exists in the source. || Verify any under-18 dose against a children's formulary before administration.