Hand-Foot-and-Mouth Disease

Hand-foot-and-mouth disease is a common viral illness caused by an enterovirus — most often coxsackievirus A16, with enterovirus A71 and, increasingly, coxsackievirus A6 also well documented as causes.^[1][2] It mostly affects young children, though it can occur at any age, and outbreaks are most common in the summer and fall in Canadian surveillance experience (international data describes a late-spring/early-summer peak).^[3][1] The illness is highly contagious: it spreads through contact with an infected person's saliva or stool, with the virus getting onto hands or shared objects and then into someone else's mouth, and also through respiratory droplets and direct contact with fluid from a ruptured skin lesion.^[3][1] A person is most contagious during the first week of illness, but the virus continues to be shed in stool for several weeks after symptoms resolve — one Canadian source specifies up to about 4 weeks — which is why hand hygiene remains important well after a child looks and feels better.^[3][2]

The classic pattern is painful mouth ulcers together with a rash of red spots, often with small blisters on top, on the palms and soles and sometimes the buttocks, groin, knees, or elbows — typically preceded by a day or two of fever, poor appetite, and general malaise.^[3][2] HFMD is generally a mild, self-limited illness that resolves on its own within about 7-10 days, and there is no licensed antiviral treatment — management is entirely supportive.^[3][2][1] The single most important practical issue for a pharmacist to anticipate is hydration: painful oral ulcers can meaningfully reduce a young child's willingness to eat or drink, and dehydration — not the rash, and not the virus itself — is the most common reason a child with HFMD ends up needing medical care.^[2] A smaller, genuinely important secondary role is correcting two common counselling gaps: that aspirin should never be used for a child's fever given Reye syndrome risk, and that OTC topical oral anesthetics carry specific pediatric age cautions that make them a poor first reach for a young child's mouth pain.

The typical course

Symptoms usually start suddenly, 3 to 6 days after exposure to the virus (the incubation period).^[2][1] A low-grade fever is often the first sign, lasting roughly 1-2 days, together with reduced appetite, a sore throat, and general malaise.^[2][3] About 1-2 days after the fever begins, painful ulcers appear in the mouth — on the tongue, gums, inner cheeks, and sometimes the soft palate — starting as small vesicles surrounded by a thin halo of redness that quickly rupture into shallow, painful ulcers with a grey-yellow base.^[2][1] Around the same time or shortly after, a rash of red spots, often with small blisters on top, appears on the palms of the hands and soles of the feet, and frequently on the buttocks and sometimes the knees, elbows, or groin.^[3][2] The skin lesions are typically small (roughly 2-6 mm), non-pruritic, and not particularly painful, and they resolve without scarring as shallow ulcers if they rupture.^[1] The overall illness — fever, mouth ulcers, and rash together — usually resolves within about 7-10 days.^[3][2]

Characteristic HFMD rash on the palms. (James Heilman, MD, CC BY-SA 3.0, Wikimedia Commons)

Characteristic HFMD rash on the sole. (James Heilman, MD, CC BY-SA 3.0, Wikimedia Commons)

Oral vesicles/ulcers of HFMD on the soft palate and oropharynx — the finding most responsible for reduced oral intake. (Public domain, Wikimedia Commons)

Distinguishing HFMD from other vesicular/exanthematous illnesses

The combination of oral ulcers plus a palm/sole/buttock-distribution rash is genuinely distinctive, but three other conditions are worth actively ruling out, particularly when the presentation is incomplete or the child appears more unwell than typical HFMD would suggest.

^[1]

• Age is the dominant factor: HFMD mostly affects young children, most often those under 5 years of age and especially those in daycare or preschool settings, though it can occur at any age, including in adults (most often parents or caregivers of an affected child).^[3][1]
• Close-contact childcare and school settings are the classic setting for outbreaks, given how efficiently the virus spreads through saliva, shared toys and surfaces, and stool contamination.^[3]
• Seasonality: outbreaks are most often described as a summer/fall phenomenon in Canadian sources; international surveillance data more often describes a late-spring/early-summer peak, with a positive correlation between HFMD incidence and warmer, more humid conditions.^[3][1]
• Causative strain matters for severity, not just diagnosis: coxsackievirus A16 causes the clear majority of typical, mild Canadian cases, while enterovirus A71 is specifically associated with the rare but more severe neurologic and cardiopulmonary complications discussed under Red Flags/Refer, and coxsackievirus A6 has increasingly been recognized as a cause of more extensive or atypical-appearing rashes.^[1]
• Transmission occurs through direct contact with saliva, blister fluid, or stool; through respiratory droplets; and via contaminated hands, shared utensils, or surfaces — all genuinely relevant to the hygiene counselling in Non-Pharmacologic Management.^[3][1]
• Immunocompromised status is not a risk factor for acquiring HFMD specifically, but does lower the threshold for medical assessment if a child does become infected (see Special Populations).

Diagnosis is clinical

HFMD is diagnosed clinically, based on the characteristic combination of oral ulcers and a palm/sole (often also buttock) rash, together with a compatible history (young child, daycare/school exposure, 3-6 day incubation period). Laboratory testing is not routinely needed.^[1]

When testing is actually used

Real-time PCR of a lesion swab can identify coxsackievirus or another enterovirus, and light microscopy of a lesion scraping can help distinguish HFMD from varicella-zoster or herpes simplex virus when the presentation is genuinely ambiguous — but in practice, these tools are reserved for atypical presentations, diagnostic uncertainty, immunocompromised patients, suspected severe/enterovirus A71-type disease, or outbreak/public-health surveillance purposes, rather than for a typical, well-appearing child with the classic distribution.^[1] Serology is not a sensitive diagnostic tool but can be used to monitor recovery in specific clinical or research contexts.^[1]

Differential diagnosis

See Recognize the Condition for the full herpangina/varicella/herpetic-gingivostomatitis comparison table. In practice, the most useful bedside discriminators are: oral-only involvement (favours herpangina), a widespread pruritic rash in mixed stages of healing across the trunk and scalp (favours varicella), and diffuse gingival inflammation with a high fever and no palm/sole rash (favours herpetic gingivostomatitis).^[1]

• Provide effective symptomatic relief from fever and oral pain using medications that are actually appropriate for a young child.
• Protect and monitor hydration status as the central practical goal — this is the single factor most likely to determine whether a child needs to be seen medically.
• Avoid genuinely harmful or age-inappropriate self-care choices: aspirin, and topical oral anesthetics used outside their age-appropriate cautions.
• Give accurate, realistic expectations about the self-limited, roughly 7-10 day course.
• Counsel correctly on Canadian daycare/school attendance guidance, rather than defaulting to unnecessarily strict exclusion.
• Reinforce hand hygiene and surface/toy cleaning, given how contagious HFMD is and how long viral shedding in stool continues after symptoms resolve.
• Recognize and escalate the specific red flags — dehydration and the enterovirus A71-type neurologic warning signs — that fall outside routine self-care.

Comfort and feeding measures

• Offer cold, soft, bland foods and liquids — yogurt, applesauce, cold soup, milk, ice chips, and popsicles are generally well tolerated; avoid citrus fruit/juice, tomato-based foods, and anything spicy, salty, or crunchy that can irritate the oral ulcers.^[3][2]
• Offer fluids frequently in small amounts rather than expecting a child to drink a normal volume at once — this is often the single most effective practical strategy for maintaining hydration through a painful mouth.
• Do not attempt to pop, lance, or otherwise manipulate the skin blisters — they heal better left alone, and manipulating them adds infection risk without any benefit.^[2]
• A cool compress can offer comfort for uncomfortable skin lesions if the child tolerates it; loose, breathable clothing avoids friction over the rash.

Hand hygiene and household/childcare hygiene

• Frequent handwashing with soap and water — for the affected child, caregivers, and household or classroom contacts — is the single most effective prevention strategy for limiting HFMD transmission.^[1]
• Clean and disinfect commonly touched surfaces and shared toys with soap and water, followed by a disinfecting (e.g., bleach) solution where appropriate.^[2]
• Remember that viral shedding in stool continues for weeks after symptoms resolve (up to about 4 weeks per one Canadian source), so hand hygiene — especially after diaper changes and toileting — remains genuinely important even once the rash and fever are gone.^[3]

Daycare and school attendance — genuinely permissive Canadian guidance

Routine exclusion from daycare or school is not required for HFMD in Canadian public health guidance: a child may continue to attend if they feel well enough to take part in normal activities, and the risk to other children is limited where reasonable hygiene practices are followed.^[2] Two Ontario public health units independently describe the same approach — one specifically notes that routine exclusion is not indicated since this is not a reportable disease, while the other suggests keeping a child home specifically if they are drooling with mouth blisters, or have a weeping (open, draining) rash on the hands, as a practical way to reduce transmission during the most contagious early days, without treating this as a mandatory public-health exclusion. Counsel families accordingly, rather than defaulting to a stricter chickenpox-style exclusion that this illness does not actually call for.

Infants under 6 months

Antipyretic/analgesic options are narrower in this group: acetaminophen can be used at a correct weight-based dose, but ibuprofen should not be given without first speaking to a doctor or health care provider.^[4] Because this age group also cannot reliably communicate symptoms, and benzocaine oral products are specifically not authorized under 2 years of age in Canada, non-pharmacologic comfort measures and closer hydration monitoring should be emphasized over reaching for a topical product.^[5]

Immunocompromised children

A lower threshold for medical assessment is appropriate — the illness can be more prolonged or, rarely, more severe in this group, and typical reassurance-focused counselling should be adjusted accordingly.

Daycare- and school-age children

This is the population in which HFMD is most often seen and most often transmitted. Reinforce the genuinely permissive Canadian attendance guidance described in Non-Pharmacologic Management, alongside real hand-hygiene and surface-cleaning counselling, since this combination — rather than exclusion — is what Canadian public health sources actually recommend for limiting outbreak spread.^[2]

Adults

HFMD can occur at any age, most often in parents or other caregivers of an affected child. Presentation is generally similar to that in children, though atypical or more extensive rashes have increasingly been reported with certain strains such as coxsackievirus A6.^[1] The same symptomatic-care principles apply, with aspirin avoidance specifically relevant to children and teenagers rather than adults.

• Reassess hydration status daily while symptoms are active — reduced urination, absent tears, or increasing lethargy should prompt medical reassessment rather than simply continuing home care.^[2]
• Expect resolution of fever, oral ulcers, and rash within about 7-10 days; a course meaningfully longer than this, or a new fever after apparent resolution, should prompt reassessment of the diagnosis rather than assuming a slow but normal course.^[3][2]
• Continue hand hygiene and surface/toy cleaning for at least several weeks after symptoms resolve, given ongoing fecal viral shedding — this is a genuinely useful piece of counselling that families often do not expect, since it runs well past the point the child looks and feels well.^[3]
• Confirm families understand the specific "watch for" list (dehydration signs; new lethargy, irritability, ataxia, or myoclonic jerking; laboured breathing) rather than leaving follow-up entirely to their own judgment.
• For a family using a topical oral anesthetic despite counselling against it in a young child, confirm they understand correct minimal dosing and the specific warning signs of methemoglobinemia (pale, grey, or bluish skin color; unusual fatigue; shortness of breath) or of lidocaine toxicity (confusion, seizure-like activity), and to seek immediate care if these occur.^[5]

1. Signs of dehydration develop or worsen despite consistent analgesia and small, frequent fluid offerings: arrange prompt medical assessment rather than continuing to manage at home — oral or, if needed, intravenous rehydration may be required.
2. Fever remains high or poorly controlled despite correctly dosed acetaminophen (with ibuprofen added once intake allows): reassess rather than simply increasing dose frequency beyond the product monograph.
3. New lethargy, irritability, unsteady gait/ataxia, myoclonic jerking, or laboured breathing at any point: this is an urgent same-day medical assessment, not a "watch and wait" situation — these are the specific warning signs of more severe enterovirus-associated disease.
4. Rash or ulcers not improving, or actively worsening, well beyond the typical 7-10 day course: reconsider the diagnosis (see the herpangina/varicella/herpetic-gingivostomatitis differential) rather than assuming an unusually slow but still-typical case.
5. Signs of a secondary bacterial skin infection at a scratched or broken lesion (spreading redness, warmth, pus, increasing pain): refer for medical assessment rather than continuing routine HFMD self-care alone.

• Recommending or allowing aspirin for a child's or teenager's fever — this specifically increases Reye syndrome risk and should never be a self-care recommendation for a viral illness.^[4]
• Reaching for an OTC benzocaine oral gel in a child under 2 years of age, or viscous lidocaine 2% in any young child, for teething- or HFMD-related mouth pain — both carry specific, genuine safety concerns in this age group.^[5]
• Starting or continuing ibuprofen in a child who is not drinking reasonably well, or in an infant under 6 months without medical advice.^[4]
• Popping or lancing the skin blisters — this adds infection risk without speeding healing.^[2]
• Defaulting to strict, chickenpox-style daycare/school exclusion — Canadian public health guidance for HFMD is genuinely more permissive, and over-restrictive advice is not what current sources recommend.^[2]
• Underestimating how much oral pain can reduce a young child's fluid intake — dehydration, not the rash itself, is the most common reason this illness ends up needing medical care.^[2]
• Assuming every case is uniformly mild and missing the specific neurologic warning signs (lethargy, ataxia, myoclonic jerking) that would suggest a more severe enterovirus A71-type presentation.^[1]
• Ordering or requesting viral testing routinely for a typical, well-appearing child — this is a clinical diagnosis in the great majority of cases.^[1]

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.

Antipyretics/Analgesics — First-Line Symptomatic Relief

Appropriate for fever and oral-lesion pain at any point in the illness. Hydration status determines whether ibuprofen is appropriate.

Topical Oral Comfort Measures — Use With Real Caution in Young Children

Symptomatic relief of painful oral ulcers. Both agents below carry specific, genuine pediatric safety concerns; favour systemic analgesia and non-pharmacologic comfort measures as the first reach in young children.

Avoid in Children and Teenagers

A standing pediatric fever-management rule, not specific to HFMD.