# Photodermatitis - Category: acute - Review status: reviewed (every claim checked against a document named on this page) - Sources: DailyMed SetID 8274ca80-e7d3-4f4f-9901-cc5c589b4fef sections 1 and 2.2, https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8274ca80-e7d3-4f4f-9901-cc5c589b4fef · Levocetirizine dihydrochloride tablets US prescribing information, sections 1 and 2 Dosage and Administration (DailyMed SetID 8274ca80-e7d3-4f4f-9901-cc5c589b4fef) · Sathe NC, Gillespie E. Photosensitivity and Photodermatoses. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Updated 2026 Jan 31. Bookshelf ID: NBK431072; PMID: 28613726. - Verified date: 2026-08 ## Verified against - DailyMed SetID 8274ca80-e7d3-4f4f-9901-cc5c589b4fef sections 1 and 2.2, https://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?setid=8274ca80-e7d3-4f4f-9901-cc5c589b4fef ## Treatment metadata - Levocetirizine — 5 mg — oral.solid ## Complete treatment card ```text PHOTODERMATITIS Sources: DailyMed SetID 8274ca80-e7d3-4f4f-9901-cc5c589b4fef sections 1 and 2.2, https://dailymed.nl m.nih.gov/dailymed/drugInfo.cfm?setid=8274ca80-e7d3-4f4f-9901-cc5c589b4fef · Levocetirizine dihydrochloride tablets US prescribing information, sections 1 and 2 Dosage and Administration (DailyMed SetID 8274ca80-e7d3-4f4f-9901-cc5c589b4fef) · Sathe NC, Gillespie E. Photosensitivity and Photodermatoses. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2026 Jan-. Updated 2026 Jan 31. Bookshelf ID: NBK431072; PMID: 28613726. Review status: REVIEWED against the source listed above (2026-08) IS IT THIS? - reference only, to read alongside your own examination SYMPTOMS - what the patient reports (7) - Ask how soon after light the rash comes, whether it repeats, how it swings with season, and how long it lasts once exposure stops [rash] - A reaction within minutes suggests solar urticaria; one appearing hours to days later suggests polymorphic light eruption or photoallergy [rash · urticaria] - A long-standing rash with little seasonal swing points to lupus of the skin or chronic actinic dermatitis [rash] - Review prescriptions, over-the-counter drugs, herbal remedies, topicals, fragrances, and plant or chemical contact at work or play - Thiazide diuretics and doxycycline are the usual drug culprits - Joint pains, mouth ulcers, Raynaud or tiredness suggest connective tissue disease; belly pain, nerve symptoms or dark urine suggest acute porphyria [abdominal pain · fatigue · mouth ulcers] - In a child, poor growth, neurological problems or early cancers raise an inherited photosensitivity syndrome [failure to thrive] SIGNS - what you find (8) - The rash sits on face, neck, V of the chest, backs of forearms and hands, sparing skin under clothing [rash] - Sharp cut-offs at collar, jewellery, watch strap or hairline strongly support a light-driven rash [rash] - Skin usually in the sun, like the face in polymorphic light eruption, may be spared through hardening [rash] - Papules, plaques, vesicles and prurigo nodules fit the idiopathic group; wheals fit solar urticaria; eczematous plaques fit photoallergy or chronic actinic dermatitis [blisters · papules · plaques · urticaria · vesicles] - Ring-shaped plaques that worsen in the sun fit subacute cutaneous lupus [plaques] - Blisters, fragile skin and scarring on exposed sites raise porphyria, above all porphyria cutanea tarda [blisters · scarring] - Examine beyond the skin - scalp, nails, mucous membranes and for systemic disease - Abnormal nailfold capillaries support dermatomyositis; poikiloderma and sun damage suggest long-standing photosensitivity or a genodermatosis TESTS (12) - Testing follows the clinical suspicion and is tailored to the likeliest diagnosis - Start with history and examination, then targeted lab, photobiologic and histology testing - Phototesting, in specialist centres only, defines the action spectrum and reproduces the disease - Minimal erythema dose testing finds abnormal sensitivity to UVA or UVB and separates true photodermatoses from normal skin - Provocative phototesting over several days may reproduce the rash, but misses a high proportion of cases - Photopatch testing, alongside ordinary patch testing, is for suspected photoallergic contact dermatitis - ANA and ENA panels are for suspected connective tissue disease, not for routine screening - Blistering or painful photosensitivity means porphyrins in blood, urine and stool - Biopsy with histology and direct immunofluorescence helps where autoimmune, chronic actinic and idiopathic pictures overlap - Biopsy results are frequently non-specific and need the clinical context to read - Suspected inherited syndromes need specialist testing - cell survival after UV, DNA repair studies, gene sequencing - Finding these early matters - skin cancer risk is much raised and surveillance has to be close IF NOT THIS - what else fits (12) - Idiopathic group: polymorphous light eruption, actinic prurigo - Autoimmune group: cutaneous lupus and dermatomyositis - Metabolic group: the porphyrias and pellagra - Drug-induced: methotrexate, doxycycline - Genetic group: xeroderma pigmentosum - Persistent light-pattern rash: think cutaneous lupus, told apart by systemic features, serology and histology - Dermatomyositis where there is proximal muscle weakness or Gottron papules - Suspect a drug where medication changed recently and the border is sharp - Porphyria where there is blistering, fragile skin and scarring on exposed sites - Inherited syndromes begin early in life, with multisystem findings and raised cancer risk - Toxic epidermal necrolysis and Stevens-Johnson syndrome can take a light distribution - Dose, delay and distribution separate phototoxic from photoallergic reactions Source StatPearls "Photosensitivity and Photodermatoses" - disease-level clinical article Status traced to the source above 1. LEVOCETIRIZINE [1st line] Adult 5 mg PO once daily in evening (2.5 mg once daily may suffice). - While symptoms persist; review at 4-6 weeks Peds Age 6-11y: 2.5 mg (1/2 scored tablet) PO once daily in evening; age <6y: use oral solution. Source DailyMed SetID 8274ca80-e7d3-4f4f-9901-cc5c589b4fef sections 1 and 2.2, https://dailymed .nlm.nih.gov/dailymed/drugInfo.cfm?setid=8274ca80-e7d3-4f4f-9901-cc5c589b4fef Why Standard second-generation antihistamine dose for the itch of photodermatitis/sunburn dermatitis; dosing does not change with the trigger for the itch. Caution Severe blistering sunburn, signs of drug-induced phototoxicity, or suspicion of an underlying connective tissue disease. Evening dosing suits itch that is often worse at night. Do not combine with cetirizine - levocetirizine is cetirizine's active component, so together they double the dose. Reduce to 2.5 mg in mild renal impairment. Does not treat severe blistering sunburn or an underlying phototoxic/connective tissue disease - it is symptomatic itch relief only. Egypt ZALKEVOR 5 MG 10 F.C.TABS. EL-OBOUR > RE... 5.50 EGP (0.55/unit) RHIPGIC 5 MG 30 F.C. TABS. P & C LABS 19.50 EGP (0.65/unit) LERGOPAN 5 MG 10 F.C.TABS. PHAROPHARMA 7.50 EGP (0.75/unit) LEVOCITRONE 5 MG 10 F.C.TABS. EGYPHAR 21.00 EGP (2.10/unit) RAMATRIZINE 5 MG 30 F.C.TABS. EGPI > RAMAPH... 96.00 EGP (3.20/unit) LEVOHISTAM 5 MG 30 F.C.TABS. EGPI > UTOPIA 117.00 EGP (3.90/unit) ARAXILEVE 5 MG 30 ORO-DISPERSIBLE TABS. JEDCO INT. CO. FOR PHARMACEUTICA... 51.00 EGP LEVCET 5MG 20 ORODISSOLVABLE TABS. MARCYRL PHARMACEUTICAL INDUSTRIES (MPI) 85.00 EGP MERVOZA 2.5MG/5ML SYRUP 120 ML GLOBAL NAPI P... 8.00 EGP -> ? strength differs, ? different route - not oral solid MODALLERGE 0.5MG/ML ORAL SOL. EGPI > MODERN... 8.00 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)