# Drug Allergy - Category: acute - Review status: reviewed (every claim checked against a document named on this page) - Sources: Egyptian National Drug Formulary - endocrine.pdf, Prednisolone monograph (chapter PDF p183) · Egyptian National Drug Formulary - respiratory-2026.pdf, Cetirizine monograph (chapter PDF p14) - Verified date: 2026-08 ## Verified against - Egyptian National Drug Formulary - endocrine.pdf, Prednisolone monograph (chapter PDF p183) - Egyptian National Drug Formulary - respiratory-2026.pdf, Cetirizine monograph (chapter PDF p14) ## Treatment metadata - Cetirizine — oral.solid - Prednisolone — oral.solid ## Complete treatment card ```text DRUG ALLERGY Sources: Egyptian National Drug Formulary - endocrine.pdf, Prednisolone monograph (chapter PDF p183) · Egyptian National Drug Formulary - respiratory-2026.pdf, Cetirizine monograph (chapter PDF p14) Review status: REVIEWED against 2 sources listed above (2026-08) IS IT THIS? - reference only, to read alongside your own examination RED FLAGS (4) - Anaphylaxis, SJS, TEN, AGEP and DRESS are the reactions carrying serious morbidity and mortality - Asthma, COPD, coronary artery disease and mastocytosis raise the risk of dying from anaphylaxis - TEN mortality runs about 10% to 50% and belongs in a unit that can treat burns - Never drug-challenge after a Type II, III or IV reaction such as TEN, SJS, DRESS or AGEP SYMPTOMS - what the patient reports (5) - Type I reactions are immediate: urticarial rash, itching and flushing; severe ones add angio- oedema, hypotension and anaphylaxis [hypotension · itching · oedema · rash · urticaria] - Anaphylaxis starts within minutes to a few hours - hives, itching, swelling of the lips, tongue and uvula, and low blood pressure [hypotension · itching · urticaria] - Type II reactions are late, symptoms typically 5 to 8 days after the drug; Type III can take weeks - DRESS begins 2 to 8 weeks after the drug is started, with fever and a widespread rash [fever · rash] - Ask in the patient's own words what the reaction was, when it began, when it settled, and how long after the dose it started SIGNS - what you find (6) - Facial swelling or pharyngeal swelling can obstruct the airway and cause respiratory failure in anaphylaxis [facial swelling] - SJS and TEN start on the face as an erythematous rash and spread; target-like lesions and flaccid blisters first, then sheet-like detachment of the skin and erosions [blisters · rash · redness] - Mucous membranes can be involved in SJS and TEN as well as skin - AGEP is hundreds of sterile pinhead-sized pustules appearing rapidly on a background of oedematous erythema [oedema · pustules · redness] - DRESS adds facial swelling and lymphadenopathy to the rash, with liver, kidney or lung involvement [facial swelling · lymphadenopathy · rash] - A fixed drug eruption recurs at the same site: erythematous plaques with a grey centre on lips, tongue, genitalia, face or hands and feet [rash · redness] TESTS (6) - Tryptase can rise after a Type I reaction and after anaphylaxis - draw within 1 to 3 hours, and a normal level does not exclude it - Baseline tryptase varies between people, so serial samples are needed to confirm a true rise - Skin detachment under 10% of body surface is SJS, 10 to 30% is SJS/TEN overlap, over 30% is TEN - DRESS shows eosinophilia and atypical lymphocytosis - Intradermal testing detects Type I reactions - a wheal and flare within 15 to 20 minutes; patch testing read at 48 to 96 hours detects Type IV - Naranjo score 9 or more strongly indicates a drug reaction, 5 to 8 probable, 1 to 4 possible, 0 in doubt IF NOT THIS - what else fits (5) - Pseudoallergic reactions look allergic but are not immune - vancomycin flushing is the everyday example, and slowing the infusion prevents it - Idiosyncratic reactions are neither immune nor inflammatory - dapsone haemolysis in G6PD deficiency, tinnitus after a single dose of aspirin - Drug-induced autoimmunity: a lupus-like illness after isoniazid, phenytoin, procainamide or hydralazine - Type I culprits are beta-lactams, quinolones and platinum chemotherapy; anaphylaxis most often follows NSAIDs, antibiotics and radiocontrast - SJS and TEN follow carbamazepine, sulfamethoxazole, phenytoin or lamotrigine; DRESS follows phenytoin, carbamazepine, lamotrigine, co-trimoxazole, dapsone, vancomycin, rifampicin, ethambutol or isoniazid Source StatPearls "Adverse Drug Reactions" (NBK599521) - the parent chapter; drug allergy is its Type B hypersensitivity section, and this card is scoped to that Status traced to the source above 1. CETIRIZINE [1st line] Adult 10 mg once daily by mouth - As directed, until the reaction settles after the causative drug is stopped Peds 2 to under 6 years: 2.5 mg once or twice daily 6 to under 12 years: 5 mg twice daily (or 10 mg once, depending on severity) 12 years and over: 10 mg once daily (Oral: children 2-6 years 2.5 mg once or twice daily; children 6-12 years 5 mg twice daily (or 10 mg once, depending on severity); adolescents over 12 years 10 mg once daily.) Source Egyptian National Drug Formulary - respiratory-2026.pdf, Cetirizine monograph (chapter PDF p14) Why Oral antihistamine to control itching, urticaria, and rash from a drug allergy once the culprit drug is stopped; first-line for a mild-to-moderate reaction. Caution Does not treat anaphylaxis - for stridor, wheeze, facial/tongue swelling, or hypotension, give IM adrenaline immediately and arrange emergency transfer; do not rely on an antihistamine. Sedation is possible, though less than with first-generation antihistamines; caution with driving/operating machinery. Reduce the dose in significant renal impairment. Watch for skin blistering or mucosal involvement (possible Stevens-Johnson syndrome/TEN) - stop the drug and refer urgently rather than treating as a simple rash. Egypt EPIRIZINE 10 MG 10 TABS. EIPICO 15.50 EGP (1.55/unit) CETRITIN 10MG 20 TAB. EL NILE. 42.00 EGP (2.10/unit) TOMAZINE 10MG 30 F.C. TABS. ALFACURE PHAR... 63.00 EGP (2.10/unit) CETRAK 10 MG 20 TABS. PHARCO 68.00 EGP (3.40/unit) HISTAZINE-1 10 MG 20 TABS. AMRIYA 68.00 EGP (3.40/unit) ZYRTEC 10 MG 20 TAB. GLAXO SMITHKLINE 100.00 EGP (5.00/unit) CETRICHEW 10MG 20 CHEWABLE F.C. TABS. AL ROWAD PHARMACEUTICAL INDUSTRIAL... 15.00 EGP HISTA CHEW 10 MG 20 CHEWABLE TAB. ARAB CAPS > ADVOCURE 15.00 EGP LERGFREE 5MG/5ML SYRUP 120ML DEBEIKY 9.00 EGP -> ? strength differs, ? different route - not oral solid EPIRIZINE 5MG/ML SYRUP 60 ML EIPICO 19.00 EGP -> ? strength differs, ? different route - not oral solid 2. PREDNISOLONE [add-on - not a substitute] Adult 5 to 60 mg/day as a single dose or in 2 to 4 divided doses, tapered to the lowest dose that controls symptoms - Short course, tapered off; avoid abrupt withdrawal if dose is 40 mg/day or more, or treatment has run 3 weeks or more Peds General anti-inflammatory/immunosuppressive dosing: 0.1 to 2 mg/kg/day (or 4 to 60 mg/m2 BSA/day) in 1 to 4 divided doses; use the lowest dose that controls the reaction and taper gradually. Source Egyptian National Drug Formulary - endocrine.pdf, Prednisolone monograph (chapter PDF p183) Why Added on top of an antihistamine for a more extensive or troublesome allergic reaction once the causative drug is stopped, to dampen the immune response; not a treatment for anaphylaxis itself. Caution Does not treat anaphylaxis and is not a substitute for adrenaline in a severe reaction. Avoid abrupt withdrawal after doses of 40 mg/day or more, or after 3 weeks or more of treatment - taper the dose. Use with caution in diabetes (raises blood glucose), peptic ulcer disease, active or latent infection (including TB, which is not rare in Egypt), and osteoporosis. Watch for skin blistering or mucosal involvement (possible Stevens-Johnson syndrome/TEN) - refer urgently rather than just adding a steroid course. Egypt HOSTACORTIN H 5MG 30 TAB. SANOFI 12.00 EGP (0.40/unit) PREDNISOLONE 5 MG 20 TABS. ARAB DRUG COM... 24.00 EGP (1.20/unit) PREDILONE 5MG 10 TAB. (25 STRIPS PACK) KAHIRA 250.00 EGP (25.00/unit) PREDNISOLONE-EVA 5 MG 30 ORODISPERSIBLE TABS. EVA PHARMA 79.50 EGP SOLUPRED ORO 5 MG 30 ORODISPERSIBLE TABS. SANOFI WINTHROP > SANOFI 84.00 EGP PREDNISOLONE 20 MG 20 ORODISPERSIBLE TABS. ARAB DRUG COMPANY (ADCO) 115.00 EGP XILONE 20 MG 20 ORODISPERSABLE TABS. EUROPEAN EGYPTIAN PHARM. IND. 142.00 EGP DISPRELONE-OD 20 MG 30 ORODISPERSABLE TABS. ANDALOUS PHARMA 202.50 EGP ACETASEE 1% EYE DROPS (SUSP.) 5 ML RAMEDA 7.50 EGP -> ? strength differs, ? different route - not oral solid PREDNIS 5MG/5ML SYRUP 100 ML PHAROPHARMA 9.50 EGP -> ? strength differs, ? different route - not oral solid Prices are indicative (dataset snapshot 2026-06); verify with the pharmacy. ``` --- Dawaa Reference is a reference for prescribers, not a medical device, and does not replace clinical judgement. [Privacy policy](/privacy)