{"ok":true,"entry":{"slug":"chlorpheniramine","kind":"medication","name":"chlorpheniramine","aliases":["chlorphenamine","Piriton","CPM"],"brands_sg":["Allersin","Antamin","Axcel Chlorpheniramine","Chloramine","Horamine"],"class":"first-generation antihistamine","tags":["allergy","cold-flu"],"use_for":"sneezing, runny nose and itch from allergies, cold or flu","use_after":"every 4 to 6 hours per label · when symptoms need it","use_duration":null,"take_with":"with or without food · water, milk or juice (nhs)","pros":["nhs: usually takes 30 minutes to 1 hour to work","covers allergy and cold/flu runny nose (healthhub)","sg: pharmacy-only — no prescription needed (hsa)"],"cons":["sedating — drowsiness usually lasts 4 to 6 hours (nhs)","dry mouth, blurred vision, trouble concentrating (nhs)","confusion in the elderly or very young (healthhub)"],"dose_note":"nhs, 4 mg tablets: 'the usual dose for adults and children aged 12 years old or over is 1 tablet every 4 to 6 hours. Do not take more than 6 tablets in 24 hours'; for frail older adults nhs says 1 tablet every 6 to 8 hours and 'do not take more than 3 tablets in 24 hours'; us otc drug facts (aller-chlor 4 mg) agrees: 'do not exceed 6 tablets in 24 hours'; nhs also caps self-bought use at 2 weeks; healthhub: 'do not exceed the maximum dose as recommended by your healthcare professional'; as directed on the label or by your pharmacist","dosage":null,"ul_status":null,"sg_class":"pharmacy-only","cautions":["glaucoma, prostate or bladder trouble, difficulty urinating — healthhub says tell a professional first","seizures, abnormal heart rhythm, liver disease — healthhub says tell a professional first","older adults and young children — nhs and healthhub flag restlessness, excitability and confusion","pregnant or breastfeeding — healthhub says tell a professional first"],"clashes":[{"src":["healthhub_chlor_int","fda_allerchlor_int"],"food":true,"note":"healthhub: avoid alcoholic drinks as this may increase drowsiness; the us otc label says the same","with":"alcohol"},{"src":["healthhub_chlor_int"],"note":"healthhub: do not take with or within 14 days of stopping monoamine oxidase inhibitors","with":"maois (e.g. moclobemide, selegiline)"},{"src":["fda_allerchlor_int","healthhub_chlor_int"],"note":"us otc label: ask a doctor or pharmacist first; alcohol, sedatives and tranquilizers may increase drowsiness","with":"sedatives, tranquillisers and other drowsy medicines"},{"src":["healthhub_chlor_int"],"note":"healthhub: check with a healthcare professional before taking two otc medicines together","with":"other otc medicines containing antihistamines"}],"sources":[{"id":"hsa_register","url":"https://data.gov.sg/datasets/d_767279312753558cbf19d48344577084/view","label":"HSA — Listing of Registered Therapeutic Products (open dataset on data.gov.sg, resource d_767279312753558cbf19d48344577084, pulled via datastore_search API; 30 chlorpheniramine/dexchlorpheniramine rows read)","quote":"ANTAMIN TABLET 4 mg · CHLORPHENIRAMINE MALEATE · Pharmacy Only — ALLERSIN SYRUP 4 mg/5 ml · Pharmacy Only — CHLORAMINE TABLET 4 mg · Pharmacy Only — PIRIMAT INJECTION 10 mg/ml · Prescription Only","accessed":"2026-08-27"},{"id":"hsa_reclass","url":"https://www.hsa.gov.sg/therapeutic-products/registration-of-therapeutic-products/variation-application/reclassification/list-of-reclassified-medicines/","label":"HSA — List of reclassified medicines (forensic classification definitions: POM / P / GSL)","quote":"Pharmacy-Only Medicine (P): A therapeutic product that can be obtained from a pharmacist at a retail pharmacy without a prescription … generally indicated for the short-term treatment of a minor condition or symptoms … managed by self-medication","accessed":"2026-08-27"},{"id":"healthhub_chlor","url":"https://www.healthhub.sg/medication-devices-and-treatment/medications/chlorpheniramine","label":"HealthHub (MOH Singapore) — Chlorpheniramine medication information leaflet (article last reviewed 3 June 2026)","quote":"Chlorpheniramine belongs to a group of medicines known as antihistamines … Relief of sneezing due to allergies … Relief of runny nose due to allergies, cold or flu … Relief of itch in the eyes, nose or skin","accessed":"2026-08-27"},{"id":"healthhub_chlor_how","url":"https://www.healthhub.sg/medication-devices-and-treatment/medications/chlorpheniramine","label":"HealthHub (MOH Singapore) — Chlorpheniramine leaflet, 'how should I take' section (same page)","quote":"You may take this medication with or without food … Take this medication when necessary to relieve your symptoms … Do not exceed the maximum dose as recommended by your healthcare professional","accessed":"2026-08-27"},{"id":"healthhub_chlor_safe","url":"https://www.healthhub.sg/medication-devices-and-treatment/medications/chlorpheniramine","label":"HealthHub (MOH Singapore) — Chlorpheniramine leaflet, precautions and side-effects sections (same page)","quote":"You have or have ever had: Increased eye pressure (glaucoma) … Difficulty urinating or have a history of other bladder conditions … Seizures … Abnormal heart rhythm … Liver disease … Confusion in the elderly or very young children","accessed":"2026-08-27"},{"id":"healthhub_chlor_int","url":"https://www.healthhub.sg/medication-devices-and-treatment/medications/chlorpheniramine","label":"HealthHub (MOH Singapore) — Chlorpheniramine leaflet, food and medication interactions section (same page)","quote":"Avoid alcoholic drinks as this may increase drowsiness … Do not take with or within 14 days of stopping monoamine oxidase inhibitors (MAOIs) such as moclobemide and selegiline … check with your health care professional before taking two over-the-counter medications","accessed":"2026-08-27"},{"id":"nhs_chlor_about","url":"https://www.nhs.uk/medicines/chlorphenamine-including-piriton/about-chlorphenamine/","label":"NHS — About chlorphenamine (brand names Piriton, Allerief, Pollenase; page last reviewed 14 May 2025)","quote":"Chlorphenamine is an antihistamine medicine that relieves the symptoms of allergies. It's known as a drowsy (sedating) antihistamine … Chlorphenamine usually takes 30 minutes to 1 hour to work … Wait at least 4 hours between doses","accessed":"2026-08-27"},{"id":"nhs_chlor_how","url":"https://www.nhs.uk/medicines/chlorphenamine-including-piriton/how-and-when-to-take-chlorphenamine/","label":"NHS — How and when to take chlorphenamine, 'Dosage and strength' (page last reviewed 14 May 2025)","quote":"The usual dose for adults and children aged 12 years old or over is 1 tablet every 4 to 6 hours. Do not take more than 6 tablets in 24 hours … Chlorphenamine comes as 4mg tablets","accessed":"2026-08-27"},{"id":"nhs_chlor_how2","url":"https://www.nhs.uk/medicines/chlorphenamine-including-piriton/how-and-when-to-take-chlorphenamine/","label":"NHS — How and when to take chlorphenamine, older adults and duration (same page)","quote":"The usual dose for older adults who are frail is 1 tablet every 6 to 8 hours. Do not take more than 3 tablets in 24 hours … Do not take chlorphenamine for longer than 2 weeks","accessed":"2026-08-27"},{"id":"nhs_chlor_se","url":"https://www.nhs.uk/medicines/chlorphenamine-including-piriton/side-effects-of-chlorphenamine/","label":"NHS — Side effects of chlorphenamine (page last reviewed 14 May 2025)","quote":"Drowsiness usually wears off 4 to 6 hours after a dose … Feeling dizzy or difficulty concentrating … Dry mouth … Blurred vision … Children and people aged over 65 have more chance of getting some side effects","accessed":"2026-08-27"},{"id":"fda_allerchlor","url":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=04ca3806-72be-47d4-9fea-5b0dee087683","label":"DailyMed / FDA — ALLER-CHLOR (chlorpheniramine maleate 4 mg) tablet, OTC Drug Facts 'Directions' (Rugby Laboratories; label updated 8 July 2026)","quote":"Chlorpheniramine maleate 4 mg … Antihistamine … take every 4 to 6 hours, or as directed by a doctor … adults and children 12 years and over 1 tablet. Do not exceed 6 tablets in 24 hours","accessed":"2026-08-27"},{"id":"fda_allerchlor_warn","url":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=04ca3806-72be-47d4-9fea-5b0dee087683","label":"DailyMed / FDA — ALLER-CHLOR, OTC Drug Facts 'Warnings' (same label)","quote":"Ask a doctor before use if you have glaucoma, a breathing problem such as emphysema or chronic bronchitis, difficulty in urination due to enlargement of the prostate gland … excitability may occur, especially in children","accessed":"2026-08-27"},{"id":"fda_allerchlor_int","url":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=04ca3806-72be-47d4-9fea-5b0dee087683","label":"DailyMed / FDA — ALLER-CHLOR, OTC Drug Facts drowsiness and drug-interaction warnings (same label)","quote":"Ask a doctor or pharmacist before use if you are taking sedatives or tranquilizers … alcohol, sedatives, and tranquilizers may increase drowsiness … use caution when driving a motor vehicle or operating machinery","accessed":"2026-08-27"}],"brand_certs":null,"updated_at":"2026-08-29T16:16:14.713299+08:00"},"disclaimer":"kozen-x is not a medical device and does not give medical advice. it lists what published sources have written down. absence of a record is not the same as safe."}