{"ok":true,"entry":{"slug":"guaifenesin","kind":"medication","name":"guaifenesin","aliases":["glyceryl guaiacolate","guaiphenesin"],"brands_sg":["Mucinex","Breacol","Cofen 50","Guafensin","Tonin Cough Syrup S"],"class":"expectorant","tags":["cold-flu"],"use_for":"chesty cough with phlegm — thins and loosens airway mucus","use_after":"every 12 hours per the mucinex label · with or without food","use_duration":null,"take_with":"a full glass of water · tablets swallowed whole, not crushed","pros":["all 7 sg registrations are general sale list","healthhub: may be taken with or without food","cochrane: 1 of 3 adult guaifenesin trials was positive"],"cons":["cochrane: no good evidence for or against otc cough","drowsiness, nausea, vomiting, stomach pain, diarrhoea","mucinex label: under 12 years of age — do not use"],"dose_note":"the singapore mucinex extended release 600 mg label [SIN14588P] reads 'adults and children 12 years of age and over: 1 or 2 tablets every 12 hours. Do not exceed 4 tablets in 24 hours' — a stated ceiling of 4 tablets, i.e. 2,400 mg of guaifenesin a day at that strength; the same label says 'children under 12 years of age: do not use' and 'do not crush, chew, or break tablet'; healthhub adds that if symptoms persist or worsen after one week, speak to your healthcare professional; as directed on the label or by your doctor or pharmacist","dosage":null,"ul_status":null,"sg_class":"general-sale","cautions":["cough with thick yellow or green phlegm, or blood — healthhub says say so first","fever above 38.6 °C, night sweats, weight loss or a cough over 3–4 weeks — healthhub says say so first","stomach ulcers, liver or kidney problems, copd or severe uncontrolled asthma — healthhub says say so first","pregnant, planning to be, or breastfeeding — healthhub says say so first"],"clashes":[{"src":["healthhub_guai_precautions"],"note":"healthhub asks that you tell your healthcare professional what else you are taking; no specific interaction is named","with":"other medicines, supplements, traditional or herbal remedies"},{"src":["ndf_mucinex"],"note":"the mucinex label caps the total at 4 tablets in 24 hours, so combination products can double up unnoticed","with":"other cough or cold products containing guaifenesin"}],"sources":[{"id":"healthhub_guai","url":"https://www.healthhub.sg/medication-devices-and-treatment/medications/guaifenesin","label":"HealthHub (MOH Singapore) — Guaifenesin, uses / administration / side effects (article last reviewed 16 Dec 2025)","quote":"This medication is also known as guaiphenesin. It is an expectorant that works by thinning and loosening mucus in the airways … This medication may be taken with or without food. For syrups, shake the bottle well before use.","accessed":"2026-08-27"},{"id":"healthhub_guai_precautions","url":"https://www.healthhub.sg/medication-devices-and-treatment/medications/guaifenesin","label":"HealthHub (MOH Singapore) — Guaifenesin, precautions and side-effect sections (article last reviewed 16 Dec 2025)","quote":"stomach ulcers, liver or kidney problems and lung conditions e.g. Chronic Obstructive Lung Disease (COPD) or severe uncontrolled asthma … a cough with thick yellow or green phlegm or mucus, or blood … Drowsiness … Nausea … Diarrhoea","accessed":"2026-08-27"},{"id":"ndf_mucinex","url":"https://www.ndf.gov.sg/about-drugs/product-information/sin14588p/","label":"MOH National Drug Formulary — MUCINEX EXTENDED RELEASE TABLETS 600MG [SIN14588P], Dosing and Contraindications","quote":"adults and children 12 years of age and over: 1 or 2 tablets every 12 hours. Do not exceed 4 tablets in 24 hours … children under 12 years of age: do not use … Forensic Classification GENERAL SALE LIST","accessed":"2026-08-27"},{"id":"hsa_register_guai","url":"https://data.gov.sg/datasets/d_767279312753558cbf19d48344577084/view","label":"HSA register of therapeutic products (data.gov.sg d_767279312753558cbf19d48344577084) — 7 guaifenesin rows, filtered locally 27 Aug 26","quote":"MUCINEX EXTENDED RELEASE TABLETS 600MG … General Sale List … BREACOL COUGH SYRUP 100 mg/5 ml … General Sale List … COFEN 50 COUGH MIXTURE … GUAFENSIN SYRUP 20MG/ML … TONIN COUGH SYRUP S","accessed":"2026-08-27"},{"id":"cochrane2014","url":"https://europepmc.org/article/PMC/PMC7061814","label":"Cochrane Database of Systematic Reviews — OTC medications for acute cough in children and adults in community settings (Smith, Schroeder, Fahey 2014; PMC7061814)","quote":"Three trials compared the expectorant guaifenesin with placebo; one indicated significant benefit, whereas the other two did not … There is no good evidence for or against the effectiveness of OTC medicines in acute cough","accessed":"2026-08-27"}],"brand_certs":null,"updated_at":"2026-08-29T16:16:21.812539+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."}