# Corn and Callus - Category: chronic - Review status: reviewed (every claim checked against a document named on this page) - Sources: NICE Clinical Knowledge Summaries: Corns and calluses 2021 · Salactol Collodion (salicylic acid 16.7% + lactic acid 16.7%) SmPC sections 4.2-4.3 (eMC product 3766) · No labelled dose - a procedure, not a medicine - Verified date: 2026-08 ## Verified against - Salactol Collodion (salicylic acid 16.7% + lactic acid 16.7%) SmPC sections 4.2-4.3 (eMC product 3766) - No labelled dose - a procedure, not a medicine - Corns - disease-level clinical article (corn-and-callus-clinical.txt) ## Treatment metadata - Salicylic acid — topical - Referral & safety-netting (no drug therapy) - Mechanical debridement and pressure offloading ## Complete treatment card ```text CORN AND CALLUS Sources: NICE Clinical Knowledge Summaries: Corns and calluses 2021 · Salactol Collodion (salicylic acid 16.7% + lactic acid 16.7%) SmPC sections 4.2-4.3 (eMC product 3766) · No labelled dose - a procedure, not a medicine Review status: REVIEWED against Salactol Collodion (salicylic acid 16.7% + lactic acid 16.7%) SmPC sections 4.2-4.3 (eMC product 3766), No labelled dose - a procedure, not a medicine, Corns - disease-level clinical article (corn-and- callus-clinical.txt) (2026-08) IS IT THIS? - reference only, to read alongside your own examination SYMPTOMS - what the patient reports (3) - Corns hurt with walking or standing but are painless to touch - Thickening keratin buildup can cause severe pain with ambulation - Interdigital soft corns can macerate and become secondarily infected or ulcerated SIGNS - what you find (6) - A flesh-colored, hard papule with a whitish core overlying a bony prominence [papules] - Hard corns typically sit on the lateral/dorsal fifth toe or over the lesser toe joints - Soft corns occur in the web spaces between toes, especially the fourth - Perpendicular pressure on a plantar corn reproduces pain by contacting the underlying bone, unlike a wart - No pinpoint bleeding (Auspitz sign) appears after paring a corn, unlike a wart - Normal plantar skin lines remain visible through a corn, unlike a wart TESTS (4) - Dermoscopy shows hyperkeratosis without the vascular or hemorrhagic dots seen in warts - Foot x-rays can show the bony prominence contributing to corn formation - Plantar pressure studies can localize areas of excess pressure causing the corn - Fasting glucose or rheumatoid factor may be checked to find an underlying cause of foot deformity IF NOT THIS - what else fits (5) - Plantar wart is the key differential, distinguished by intact skin lines and a positive Auspitz sign after paring - Poroma is on the differential list - Gout and pseudogout are included in the differential - Interdigital neuroma is a differential, particularly for web-space lesions - Palmoplantar keratoderma is on the differential list Source StatPearls "Corns" - disease-level clinical article Status traced to the source above 1. SALICYLIC ACID [1st line] Adult Apply a salicylic acid 12.6% to 40% solution or self-adhesive pad directly onto the corn or callus once daily, usually at night, after soaking the foot in warm water and paring dead skin with a pumice stone - Up to 12 weeks Peds For adults, children and the elderly. Apply once daily usually at night. Source Corns - disease-level clinical article (corn-and-callus-clinical.txt) for the strength range: "Topical keratolytic medications may be applied to the corns, including salicylic acid 12.6% to 40% as a pad or a solution." The Salactol Collodion SmPC (salicylic acid 16.7% with lactic acid 16.7%, eMC product 3766) is the held Egyptian-market example and supplies the method: "Salactol should be applied once daily usually at night. It can take up to twelve (12) weeks for resistant lesions to disappear". Why Keratolytic that softens and breaks down the thickened keratin of a corn or callus, allowing the hardened skin to be pared away; avoided where circulation or sensation is impaired because it can cause tissue damage in that setting. Caution Strictly contraindicated in diabetic patients, peripheral vascular disease, or peripheral neuropathy due to risk of tissue necrosis and foot ulceration. Protect surrounding normal skin with petroleum jelly or zinc oxide ointment prior to application. Do not apply on broken, inflamed, or infected skin. Collodion is flammable - no smoking or naked flame until it has dried. Egypt SALICYLIC ACID COLLODION 12% PAINT B.P.2001 UNIPHARMA CO. > UNIPHARMA 3.00 EGP -> ? different route - not topical SALICYLIC ACID SOAP (WEISER) 45 GM WEISER 15.00 EGP -> ? different route - not topical 2. REFERRAL & SAFETY-NETTING (NO DRUG THERAPY) [1st line] Adult Source Corns - disease-level clinical article (corn-and-callus-clinical.txt) Why Carries the referral criteria and warning signs for this condition, which apply whichever treatment is chosen. Caution RED FLAG - Patients with peripheral neuropathy / diabetes should avoid self-application of salicylic acid plasters due to risk of skin sloughing and ulceration. 3. MECHANICAL DEBRIDEMENT AND PRESSURE OFFLOADING [add-on - not a substitute] Adult Soak affected area in warm water for 10-15 minutes, gently rub hyperkeratotic tissue with pumice stone or foot file, and apply felt doughnut pads around lesion - Ongoing / 2-4 weeks Peds Ensure children wear properly fitted shoes with wide toe boxes Source No labelled dose - a procedure, not a medicine Why Offloading pressure and replacing ill-fitting shoes is necessary to prevent recurrence even after chemical keratolysis Caution Never use razor blades or sharp knives for self-trimming at home. Refer diabetic patients directly to a podiatrist or diabetic foot clinic for professional care. 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)