Burns

A burn is tissue injury caused by heat, chemicals, electricity, friction, or radiation that denatures skin protein and, beyond a certain depth, destroys the skin's normal barrier, thermoregulatory, and sensory functions.^[1] The single most useful way to think about any burn presenting to a pharmacy is along two independent axes that together determine whether it is appropriate for pharmacist-led first aid and OTC self-care, whether it needs same-day physician assessment, or whether it needs immediate emergency referral: depth (how many skin layers are destroyed) and total body surface area (TBSA) (how much of the body is affected) — plus a short list of body locations and mechanisms that override both of those and mandate referral regardless of how small or superficial the burn looks.^[2]

Scalds from hot liquids are the most common burn mechanism seen in community practice, followed by contact burns (hot surfaces, cooking equipment, curling irons) and, especially in adolescents and adults, flame burns; a smaller but clinically important minority are chemical, electrical, or radiation (sunburn) injuries, each with its own specific first-aid and referral logic covered later in this chapter.^[1] Assessing and triaging a burn that presents at the counter is a routine extension of the pharmacist's general first-aid and wound-care scope of practice, even in jurisdictions where "burn" is not yet a named condition on a formal minor-ailments prescribing list — accurate depth/TBSA assessment and a genuinely low threshold for red-flag recognition are a core patient-safety skill here, not an optional extra.

Burn depth classification

Superficial (first-degree)

Involves the epidermis only. Dry, red-to-pink, and blanches with pressure; no blistering. Moderately painful. Heals in 5-10 days without scarring — the everyday example is an uncomplicated sunburn.^[3][1]

Sunburn is the everyday example of a superficial (first-degree) burn — diffuse erythema that blanches with pressure, with no blistering. (re-ality/Steffen, CC BY 2.0, Wikimedia Commons)

Superficial partial-thickness (second-degree)

Extends into the upper (papillary) dermis. Moist, homogeneously pink-to-red, and forms blisters; blanches briskly with pressure. Exquisitely painful, since intact nerve endings are exposed. Heals in about 2-3 weeks, typically without significant scarring if kept clean and protected from infection.^[3]

A superficial partial-thickness burn with an intact blister — moist, pink-red wound bed, briskly blanching, and very painful. (Sir MemeGod, CC BY 4.0, Wikimedia Commons)

Deep partial-thickness (second-degree)

Extends into the deeper (reticular) dermis. Drier and more mottled red-white than a superficial partial-thickness burn, with sluggish or absent blanching and reduced pinprick sensation, since more nerve endings are damaged. Healing is slow and scarring is essentially unavoidable without grafting — this depth is the category most often under-recognized as "just a bad second-degree burn" when it in fact belongs in the same urgent-referral category as a full-thickness burn.^[3][2]

A deep partial-thickness burn — mottled red-white, drier, and less brisk to blanch than a superficial partial-thickness burn. (Stonegaze, CC BY-SA 4.0, Wikimedia Commons)

Full-thickness (third-degree)

Destroys the entire epidermis and dermis, and can extend into subcutaneous fat. Waxy white, leathery, mottled, or charred, and does not blanch. Classically painless at the wound centre, because cutaneous nerve endings are themselves destroyed — surrounding partial-thickness tissue is often very painful, so an absence of pain at the centre is not reassuring. Always needs specialist referral; healing without surgical grafting is not realistic for a burn of any meaningful size.^[3][2]

Full-thickness (third-degree) burn — the wound bed is stiff, white-to-charred, and non-blanching. (SMART-Servier Medical Art, Laboratoires Servier, CC BY-SA 3.0, Wikimedia Commons)

Burn depth is not always obvious on the first assessment — a burn can look more superficial in the first hours than it turns out to be. This is exactly why any burn that is not clearly and confidently superficial deserves a scheduled recheck at 24-48 hours rather than a single assessment and discharge (see Monitoring & Follow-Up).^[3]

• Scald injury from a hot beverage, cooking liquid, or bath/shower water — the single most common mechanism seen in community practice, and the leading burn mechanism in young children specifically.^[1]
• Contact with a hot surface, appliance, or cooking equipment (stovetops, curling irons/straighteners, oven racks, exhaust pipes).
• Flame exposure — house fires, barbecues, campfires, and cooking flare-ups; carries the added risk of inhalation injury (see Red Flags & Refer).
• Chemical exposure — household cleaning products (especially concentrated drain or oven cleaners), industrial/occupational chemicals, and battery acid.
• Electrical exposure — household current, high-voltage occupational exposure, and lightning strikes.
• Sun/UV exposure (sunburn) — itself a superficial burn, and repeated significant sunburns are an independent long-term skin-cancer risk factor covered in the Actinic Keratosis chapter.
• Young children and infants — thinner skin burns more deeply from the same heat exposure and duration than adult skin, curiosity and limited self-protective reflexes increase exposure risk, and this is also the age group in which non-accidental injury must always be actively considered (see Red Flags & Refer).^[4]
• Older adults — thinner, less vascular skin burns more deeply and heals more slowly; reduced mobility, sensory neuropathy, and cognitive impairment all increase both injury risk and injury severity.
• Occupational exposure to heat, flame, chemicals, or electricity (food service, industrial trades, firefighting, electrical work).
• Epilepsy, syncope, alcohol or substance intoxication, or any condition that increases the risk of prolonged, unrecognized contact with a heat source.
• Smoking, particularly smoking in bed or combined with supplemental home oxygen.
• Lower household income and substandard housing, which correlate with a higher risk of scald and house-fire burns, partly through unregulated hot-water-heater temperatures and absent or non-functional smoke detectors.

Estimating total body surface area (TBSA)

TBSA estimation guides both the referral decision and, in more significant burns, the urgency of physician assessment. Only partial-thickness and full-thickness burn is counted toward TBSA — superficial (first-degree) burn is excluded from the calculation.^[3]

The standard adult rule of nines becomes progressively less accurate the younger the child, because an infant's head and trunk make up proportionally more of total body surface area than an adult's — a formal Lund-Browder chart, which adjusts these proportions for age, is more accurate than the rule of nines in children and should be used wherever available, especially under about 10 years of age.^[1] A quick bedside estimate that works at any age: the patient's own palm plus fingers (not the palm alone) represents approximately 1% of that individual's TBSA — useful for a small or scattered burn that is awkward to estimate with the rule of nines.^[1]

Depth plus TBSA together set the severity category

^[1][2]

Screen every burn for the mechanisms and locations that override size

Before finishing the depth/TBSA assessment, specifically ask about and examine for:

• Inhalation injury — a burn sustained in an enclosed space, a house fire, or with any facial involvement should prompt a specific check for facial burns, singed eyebrows or nasal hair, soot around the nose or mouth, carbonaceous sputum, hoarseness, drooling, or difficulty swallowing (a useful mnemonic is FLASH: Facial skin, Lips, Airway sounds, Sputum, Hair).^[7]
• Circumferential extent — a burn that wraps fully around a limb, the chest, or the abdomen needs urgent assessment of distal circulation (pulses, capillary refill, sensation, movement) regardless of depth or TBSA.^[2]
• Chemical burns — identify the specific product/agent if at all possible (bring the container or read the label), and confirm decontamination has actually been started, not just planned.^[5]
• Electrical burns — ask about the voltage source, any loss of consciousness, chest pain, palpitations, or muscle pain, since the visible skin injury does not reflect the deep tissue and cardiac injury that can occur.^[6]
• Tetanus immunization status — a burn is classified as a tetanus-prone wound; confirm the patient's vaccination history at every assessment (see Choose Initial Treatment).^[9]
• Plausibility of the history, especially in an infant or young child — an inconsistent, vague, or implausible explanation, a burn pattern suggesting immersion or contact with a specific hot object, or an unexplained delay in seeking care should raise concern for non-accidental injury.^[4][8]

• Stop the burning process and limit ongoing thermal/chemical damage as early as possible — first aid in the first minutes matters more to ultimate depth than anything done afterward.
• Correctly triage every burn by depth, TBSA, location, and mechanism, and refer promptly whenever a red-flag criterion is met.
• Create and maintain a clean, moist, protected wound environment that supports the fastest possible re-epithelialization with the least scarring.
• Prevent wound infection without defaulting to unnecessary topical or systemic antibiotics.
• Control pain adequately — undertreated burn pain is common and is itself a marker that a burn may need escalation, not simply a stronger OTC product.
• Confirm and update tetanus prophylaxis for every burn that qualifies as a tetanus-prone wound.
• Recognize when a burn that looked appropriate for self-care on day 1 has not progressed as expected by follow-up, and escalate rather than continuing the same plan indefinitely.
• Support the patient through a visible or functionally significant burn with realistic expectations about healing time, scarring, and photoprotection of new skin.

Cleansing and blister management

Gently cleanse the cooled burn with mild soap and lukewarm water; pat dry rather than rubbing. Small, intact blisters leave the blister roof intact wherever possible — it functions as the body's own biological dressing and reduces infection risk; a large, tense blister, or one in a location very likely to rupture on its own (over a joint or the palm, for example), is reasonable to refer for a clinician to decompress under clean technique rather than doing so at the counter.^[11] Do not deliberately deroof every blister as routine practice — this is unnecessary for most blisters and increases both pain and infection risk without a demonstrated benefit.

Dressing selection

Superficial (first-degree) burn a simple emollient/moisturizer is sufficient; a dressing is not usually needed.

Superficial partial-thickness burn appropriate for self-care a modern moisture-retentive dressing — hydrocolloid or hydrogel — heals faster, is changed less often, and causes less pain at dressing changes than daily silver sulfadiazine cream with gauze, and is a reasonable first choice for a small, clean, uncomplicated wound.^[12][11] Alternative a non-adherent gauze dressing (for example, a petrolatum-impregnated gauze) changed daily to every 2 days is a widely available, lower-cost alternative when a hydrocolloid/hydrogel product is not accessible or affordable.

Silver sulfadiazine — special situation, not a default first choice despite decades of routine use, current comparative evidence does not show silver sulfadiazine outperforming hydrocolloid, hydrogel, or several other modern dressing categories for superficial and partial-thickness burns, and outcomes with silver sulfadiazine are consistently no better, and in several trials worse, on healing time and pain.^[11][12] It still has a role for a wound with a higher infection risk or one that is already contaminated, but should not be reached for automatically simply because it is familiar. Do not use silver sulfadiazine in an infant under 2 months of age, at or near term in pregnancy, or in a patient with known G6PD deficiency — the sulfonamide component carries a real risk of kernicterus in the newborn and hemolysis in G6PD deficiency.^[13]

Avoid topical antibiotic ointments as routine prophylaxis on a clean minor burn without a specific infection concern — bacitracin in particular causes allergic contact dermatitis often enough (it is among the most common topical allergens identified in dermatology practice) that it can itself mimic or worsen the picture it is meant to prevent; reserve a topical antimicrobial (mupirocin or fusidic acid are reasonable alternatives to bacitracin) for a wound with an actual sign of infection or a specific contamination risk.

Pain management

1st line scheduled (not only as-needed) acetaminophen and/or an NSAID such as ibuprofen for the first several days, which is when pain is worst — dosing scheduled around the clock during this window controls pain more consistently than waiting for pain to build before each dose.

Avoid topical local anesthetic sprays and gels (benzocaine-containing products, for example) on a burn — they carry a real risk of allergic contact dermatitis and, with benzocaine specifically, a rare but serious risk of methemoglobinemia that disproportionately affects infants and young children; a scheduled oral analgesic is both safer and, in practice, more effective.

Tetanus prophylaxis

A burn is classified as a tetanus-prone wound.^[9] Confirm at every burn assessment if the patient has had fewer than 3 lifetime doses of a tetanus-toxoid-containing vaccine, or their history is uncertain, give a dose now (Td or Tdap, whichever is due) and refer for tetanus immunoglobulin as well, since this is a tetanus-prone wound rather than a clean minor one. If the patient has had 3 or more documented doses, a booster is due if it has been 5 years or more since the last dose (rather than the usual 10-year interval used for a clean, minor wound) — confirm and update this at the same visit rather than assuming it was addressed elsewhere.^[9]

• Continue gentle daily cleansing with mild soap and water at each dressing change; avoid harsh antiseptics (full-strength hydrogen peroxide or povidone-iodine, for example) directly in the wound bed on an ongoing basis, since these can impair the re-epithelialization they are meant to protect.
• Elevate a burned limb above heart level where practical for the first 24-48 hours to reduce swelling.
• Splint or otherwise protect a burn overlying a joint in a position that maintains range of motion — a burn allowed to contract while healing over a joint can produce a genuine functional contracture, which is far easier to prevent than to treat afterward.
• Protect healing and newly healed skin from the sun for several months — new epithelium is more UV-sensitive and more prone to permanent pigmentation change than surrounding unburned skin; a broad-spectrum sunscreen and/or physical covering over the area is a real, not optional, part of aftercare.
• Avoid tight or constrictive clothing and jewelry over a healing burn until it is fully closed.
• Address the practical fire/scald-prevention factor when one is identifiable — a water heater set too hot, an unattended stovetop, a missing or non-functional smoke detector — since a substantial share of burns are genuinely preventable with a small, specific change.
• Acknowledge the psychological impact of a burn, especially one on a visible area (face, hands) or in a child — anxiety, sleep disruption, and reluctance to look at or touch the wound are common, and are a reasonable prompt for extra follow-up contact rather than something to dismiss as an overreaction.

Pediatrics

Children's skin is thinner than adult skin, so the same temperature and contact duration produces a deeper burn — do not assume a burn in a child is as superficial as the same-looking burn would be in an adult.^[1] TBSA-to-body-weight ratio is also higher in a young child, meaning even a burn that looks modest in absolute size represents a larger physiological insult — apply a lower referral threshold across the board in infants and young children, and use a Lund-Browder chart rather than the adult rule of nines for TBSA estimation wherever one is available.^[1] Always actively consider non-accidental injury in any infant or young child with a burn, particularly an immersion-pattern (stocking/glove distribution, sharply demarcated, symmetric) scald, a contact burn shaped like a specific object, a history that is vague, inconsistent, or changes on retelling, or any unexplained delay in seeking care — this is not an accusation to make casually, but it is a specific clinical pattern to screen for at every pediatric burn assessment, and a low threshold to involve a physician (and, where indicated, child protection services) is the safe default.^[4][8] Avoid silver sulfadiazine in an infant under 2 months of age given the kernicterus risk from the sulfonamide component.^[13] Avoid topical benzocaine-containing analgesic products in children given the methemoglobinemia risk.

Older adults

Thinner, less vascular skin burns more deeply from the same exposure and heals more slowly than in a younger adult, and comorbidities (diabetes, peripheral vascular disease, cognitive impairment) both increase burn risk and complicate healing — apply a lower referral threshold here as well, and reassess more frequently than the standard 24-48 hour recheck if healing looks at all delayed.

Pregnancy and breastfeeding

Acetaminophen is the preferred systemic analgesic throughout pregnancy. Avoid an NSAID from about 20 weeks of pregnancy onward given the established Health Canada advisory on fetal renal impairment and low amniotic fluid with later-pregnancy NSAID use; use acetaminophen instead. Avoid silver sulfadiazine at or near term given the same sulfonamide/kernicterus concern as in the newborn.^[13] For breastfeeding, acetaminophen and ibuprofen are both considered compatible; if a topical product is applied near the breast/nipple area, clean the area before a feed to minimize infant ingestion.

G6PD deficiency and immunocompromised patients

Avoid silver sulfadiazine in known G6PD deficiency given the hemolysis risk from its sulfonamide component.^[13] Apply a lower referral threshold for an immunocompromised patient of any age with a burn of any depth, given both higher infection risk and a blunted ability to mount the usual visible signs of infection.

Renal and hepatic impairment

Reduce or avoid NSAID use in significant renal impairment. Reduce the total daily acetaminophen dose in significant hepatic impairment. Neither standard dressing choice (hydrocolloid, hydrogel) needs renal or hepatic dose adjustment, since neither is systemically absorbed.

Any burn judged appropriate for OTC self-care should have a specific recheck scheduled at 24-48 hours, not left open-ended — burn depth is frequently under-called on the first assessment, and a wound that looks more concerning at the recheck (increasing pallor/mottling, new areas that are not blanching, or pain that is worse rather than better) should prompt referral at that point rather than continuing the original plan.^[3]

• Reassess depth at the 24-48 hour recheck specifically — this is the single highest-yield follow-up point in this chapter.
• Track wound size and re-epithelialization at each dressing change; a superficial partial-thickness burn should be visibly smaller and developing new pink epithelium by about 1-2 weeks.
• Teach the patient the specific signs of infection to watch for between visits — spreading redness, pain that increases rather than decreases after the first 2 days, purulent discharge, malodour, or fever — with a clear instruction to return, not simply to "watch it," if any of these appear.
• Confirm tetanus prophylaxis was actually completed, not only recommended, at the first follow-up contact.
• At 2-3 weeks, any burn that has not substantially re-epithelialized needs referral — this is itself evidence that the true depth was deep partial-thickness or full-thickness rather than superficial partial-thickness, regardless of the initial assessment.
• Once healed, counsel on sun protection of the new skin for several months and set realistic expectations about pigmentation change and scar maturation, which can continue evolving for up to a year or more.

1. Pain not controlled by scheduled acetaminophen and/or an NSAID: reassess depth and TBSA rather than simply escalating the analgesic — poorly controlled pain is itself an American Burn Association referral criterion.^[2]
2. Wound not visibly smaller or re-epithelializing by about 2 weeks: refer — this indicates the burn was deeper than initially assessed.
3. New spreading erythema, increasing pain after the first 48 hours, purulent discharge, or fever: treat as a possible wound infection and escalate — do not simply switch to a stronger topical antimicrobial without a clinical reassessment.
4. Developing stiffness or reduced range of motion at a joint the burn crosses: refer promptly for splinting/occupational or physical therapy input — a contracture is far easier to prevent early than to correct later.
5. Emerging hypertrophic or keloid scarring, or significant pigmentation change causing distress: refer for scar-management options rather than reassuring the patient it will simply fade with time.
6. A burn initially judged minor that, at the 24-48 hour recheck, shows a red-flag feature from Red Flags & Refer that was not apparent on day 1 (a new area that is not blanching, spreading involvement, or a joint/circumferential concern that was missed): refer at that point — the initial triage decision is not final.

• Applying ice or ice water to "cool it down faster" — this worsens tissue damage through vasoconstriction rather than helping.
• Applying butter, toothpaste, oil, or another home remedy, all of which trap heat and increase infection risk.
• Deliberately deroofing every blister as routine practice, rather than leaving a small intact blister alone.
• Reaching for silver sulfadiazine as an automatic default for every partial-thickness burn rather than considering a modern moisture-retentive dressing, which current comparative evidence favours for most straightforward wounds.^[11][12]
• Using silver sulfadiazine in an infant under 2 months of age, at or near term in pregnancy, or in a patient with known G6PD deficiency.^[13]
• Reaching for a topical benzocaine spray or gel for burn pain rather than a scheduled oral analgesic — this adds a real allergic-contact-dermatitis and, in children, methemoglobinemia risk without a proportionate benefit.
• Applying a topical antibiotic ointment, especially bacitracin, prophylactically to every minor burn rather than reserving it for a wound with an actual sign of infection.
• Missing a circumferential burn's compression risk because the overall TBSA looks small.
• Underestimating TBSA using the adult rule of nines in a young child, where head and trunk proportions are meaningfully different — use a Lund-Browder chart in this age group where available.^[1]
• Not asking about tetanus immunization status, or assuming someone else already checked.
• Accepting an implausible or inconsistent history for a pediatric burn without further inquiry, out of reluctance to raise the possibility of non-accidental injury.^[4]
• Treating an obvious house-fire or enclosed-space burn as a straightforward skin injury without specifically screening for inhalation injury signs.^[7]
• Assuming a small-looking electrical burn wound reflects the true extent of injury, rather than referring for the internal/cardiac injury that surface appearance does not predict.^[6]

How to use this table: Doses are adult doses and require patient-specific confirmation (renal/hepatic function, weight, allergy history). Pediatric dosing is weight-based per the current product monograph unless stated. Drug pricing is intentionally omitted. Select any drug name to open its complete Pharmasist Drug Database page.

Analgesia

Scheduled (not only as-needed) dosing for the first several days controls burn pain more consistently than dosing after pain has already built up.

Wound Dressings and Topical Antimicrobials

A modern moisture-retentive dressing is a reasonable first choice for most clean superficial and superficial partial-thickness burns appropriate for self-care; reserve a topical antimicrobial for a wound with a genuine infection risk or an actual infection sign, not as routine prophylaxis.

Tetanus Prophylaxis for a Tetanus-Prone Wound

A burn is classified as a tetanus-prone wound, not a clean minor one — confirm immunization history at every assessment and update using the shorter, wound-specific intervals below rather than the usual 10-year clean-wound interval.

Pruritus During Healing

Itch is common as a partial-thickness burn re-epithelializes; a non-sedating antihistamine is preferred for daytime use.