{"ok":true,"entry":{"slug":"diphenhydramine","kind":"medication","name":"diphenhydramine","aliases":["Benadryl","Nytol","diphenhydramine hydrochloride"],"brands_sg":["Paxidorm","Phenexpect","Suntuss","Diprodin","Diphen 10"],"class":"sedating antihistamine","tags":["allergy"],"use_for":"sneezing and runny nose; wet cough in the sg syrups","use_after":"every 4–6 hours per the benadryl allergy 25 mg label","use_duration":null,"take_with":"with or without food · half an hour before bed for sleep","pros":["healthhub: with or without food, taken when needed","benadryl label: for runny nose, sneezing, itchy eyes","9 of 10 sg registrations are pharmacy only"],"cons":["cochrane: no better than placebo for acute cough","drowsiness, dry mouth, nausea and vomiting are common","benadryl label: not to be used to make a child sleepy"],"dose_note":"no singapore label with a dose table could be found for PAXIDORM TABLETS 25 mg [SIN10851P], the plain diphenhydramine tablet; the sg phenexpect syrup label [SIN09014P] — diphenhydramine hcl 12.5 mg/5 ml with ammonium chloride — reads 'Adults: 1 to 2 teaspoonfuls to be taken 3 or 4 times a day' with '1 teaspoonful is equal to 5 ml', and the us benadryl allergy 25 mg drug facts read 'take every 4 to 6 hours. do not take more than 6 times in 24 hours' for 'adults and children 12 years and over 1 to 2 tablets', with 'children under 6 years do not use' and 'do not use … to make a child sleepy' or 'with any other product containing diphenhydramine, even one used on skin'; as directed on the label or by your doctor or pharmacist","dosage":null,"ul_status":null,"sg_class":"pharmacy-only","cautions":["glaucoma, trouble urinating or other bladder conditions — healthhub says say so first","liver or kidney disease, seizures, abnormal heart rhythm or porphyria — healthhub says say so first","pregnant, planning to be, or breastfeeding — healthhub says say so first","impaired liver or kidney function — the phenexpect label contraindicates its ammonium salt"],"clashes":[{"src":["healthhub_diphen"],"food":true,"note":"healthhub: avoid alcohol as it may increase drowsiness","with":"alcohol"},{"src":["healthhub_diphen"],"note":"healthhub: not to be taken with, or within 14 days of stopping, an maoi","with":"monoamine oxidase inhibitors (moclobemide, selegiline)"},{"src":["healthhub_diphen","dailymed_benadryl_warn"],"note":"healthhub warns of added drowsiness; the benadryl label says ask a doctor or pharmacist first","with":"other medicines that cause drowsiness; sedatives or tranquilizers"},{"src":["dailymed_benadryl_warn"],"note":"benadryl label: do not use with another diphenhydramine product, even one used on skin","with":"any other product containing diphenhydramine, including skin products"},{"src":["healthhub_diphen"],"note":"healthhub: many otc medicines contain antihistamines — check first to prevent overdosing","with":"other over-the-counter antihistamines"}],"sources":[{"id":"healthhub_diphen","url":"https://www.healthhub.sg/medication-devices-and-treatment/medications/diphenhydramine","label":"HealthHub (MOH Singapore) — Diphenhydramine, uses / administration / precautions / interactions (article last reviewed 3 Jun 2026)","quote":"antihistamines, which helps to reduce nasal secretions and sneezing … tablets may also be given to help with sleep for short periods … Do not take with or within 14 days of stopping monoamine oxidase inhibitors (MAOIs)","accessed":"2026-08-27"},{"id":"ndf_phenexpect","url":"https://www.ndf.gov.sg/about-drugs/product-information/sin09014p/","label":"MOH National Drug Formulary — PHENEXPECT SYRUP [SIN09014P] (diphenhydramine HCl 12.5 mg/5 ml with ammonium chloride), Indication and Dosing","quote":"For productive cough; symptomatic relief of sneezing and rhinorrhoea … Adults: 1 to 2 teaspoonfuls to be taken 3 or 4 times a day … 1 teaspoonful is equal to 5 ml","accessed":"2026-08-27"},{"id":"ndf_phenexpect_contra","url":"https://www.ndf.gov.sg/about-drugs/product-information/sin09014p/","label":"MOH National Drug Formulary — PHENEXPECT SYRUP [SIN09014P], Contraindications","quote":"Ammonium salts are contraindicated in the presence of impaired hepatic or renal function. Patients with narrow angle glaucoma; prostatic hypertrophy. Diphenhydramine may exacerbate porphyria.","accessed":"2026-08-27"},{"id":"ndf_paxidorm","url":"https://www.ndf.gov.sg/about-drugs/product-information/sin10851p/","label":"MOH National Drug Formulary — PAXIDORM TABLETS 25 MG [SIN10851P], product information (no dosing section published)","quote":"PAXIDORM TABLETS 25 MG [SIN10851P] … DIPHENHYDRAMINE HCL - 25 MG … Licence Holder POLYMEDIC TRADING ENTERPRISE PTE LTD … Forensic Classification PHARMACY ONLY MEDICINES … ATC code R06AA02","accessed":"2026-08-27"},{"id":"hsa_register_diphen","url":"https://data.gov.sg/datasets/d_767279312753558cbf19d48344577084/view","label":"HSA register of therapeutic products (data.gov.sg d_767279312753558cbf19d48344577084) — 10 diphenhydramine rows, filtered locally 27 Aug 26","quote":"PAXIDORM TABLETS 25 mg … Pharmacy Only … PHENEXPECT SYRUP … SUNTUSS SYRUP … DIPRODIN ELIXIR … DIPHEN 10 EXPECTORANT … XSP-BENA EXPECTORANT … BEANAMINE EXPECTORANT … HOVA EXPECTORANT … Prescription Only","accessed":"2026-08-27"},{"id":"dailymed_benadryl","url":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=702f9786-7ce9-43e4-921d-e1db09612127","label":"DailyMed / FDA OTC label — BENADRYL ALLERGY ULTRATABS (diphenhydramine HCl 25 mg tablet), Kenvue Brands LLC, Uses and Directions","quote":"temporarily relieves … runny nose, sneezing, itchy, watery eyes … take every 4 to 6 hours. do not take more than 6 times in 24 hours … adults and children 12 years and over 1 to 2 tablets","accessed":"2026-08-27"},{"id":"dailymed_benadryl_warn","url":"https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=702f9786-7ce9-43e4-921d-e1db09612127","label":"DailyMed / FDA OTC label — BENADRYL ALLERGY ULTRATABS, Warnings","quote":"Do not use to make a child sleepy … with any other product containing diphenhydramine, even one used on skin … children under 6 years do not use … Ask a doctor or pharmacist before use … sedatives or tranquilizers","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 found that antihistamines were no more effective than placebo in relieving cough symptoms … higher numbers of adverse effects in participants taking preparations containing antihistamines and dextromethorphan","accessed":"2026-08-27"}],"brand_certs":null,"updated_at":"2026-08-29T16:16:18.585742+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."}