What is the appropriate management of hand‑foot‑and‑mouth disease in a healthy adult, and what warning signs indicate the need for urgent medical attention?

Management of Hand, Foot, and Mouth Disease in Adults

Hand, foot, and mouth disease in healthy adults is managed with supportive care including oral analgesics (acetaminophen or NSAIDs), intensive moisturization of skin lesions, and specific oral hygiene measures, while urgent medical attention is required for neurological symptoms (altered consciousness, severe headache, limb weakness), signs of dehydration, or symptoms persisting beyond 2 weeks. 1

Clinical Presentation in Adults

Adults with HFMD typically present with:

• Fever and constitutional symptoms as the initial manifestation, often accompanied by malaise and sore throat 2
• Vesicular eruptions on hands, feet, and oral cavity, though adults may develop more severe and widespread rash patterns compared to children 3, 4
• Atypical presentations are increasingly common, particularly with Coxsackievirus A6, including vesiculobullous lesions on the trunk, extremities, and perioral zone 1, 4

The disease is most infectious during the first week, particularly when fever and skin lesions are present, with viral shedding continuing up to 5 days after symptom onset in adults 2

Supportive Care Management

Pain and Fever Control

• Use acetaminophen or NSAIDs for limited duration to relieve pain and reduce fever 1
• These medications address both systemic symptoms and localized discomfort from oral and skin lesions 1

Oral Lesion Management

For mild to moderate oral involvement:

• Apply white soft paraffin ointment to lips every 2 hours to prevent drying and cracking 1
• Clean mouth daily with warm saline mouthwashes or use oral sponge for comfort 1
• Use benzydamine hydrochloride oral rinse or spray every 3 hours, particularly before eating, to reduce inflammation and pain 1
• Apply chlorhexidine oral rinse twice daily as an antiseptic measure 1

For severe oral involvement:

• Consider betamethasone sodium phosphate 0.5 mg dissolved in 10 mL water as a 2-3 minute rinse-and-spit solution one to four times daily 1
• Barrier preparations such as Gengigel mouth rinse/gel or Gelclair are helpful for pain control 1
• Dilute mouthwashes by 50% if they cause excessive discomfort 1

Dietary modifications:

• Eliminate tomatoes, citrus fruits, hot drinks, and spicy, hot, raw, or crusty foods that exacerbate oral pain 1
• Drink ample fluids to maintain hydration and keep the mouth moist 1

Skin Lesion Management

For hand and foot lesions:

• Apply intensive moisturizing creams, particularly urea-containing products, to hands and feet 1
• Avoid friction and heat exposure to affected areas 1
• Do not use chemical agents or plasters to remove corns or calluses 1

For itchiness:

• Apply zinc oxide in a thin layer after gentle cleansing of affected areas 1
• Zinc oxide acts as a protective barrier and has immune-modulating properties that may reduce itchiness 1
• Avoid applying to open or weeping lesions 1
• For nighttime relief, apply zinc oxide followed by loose cotton gloves to create an occlusive barrier 1

For open sores on feet:

• Wash feet daily with careful drying, particularly between toes 1
• Avoid walking barefoot and wear appropriate cushioned footwear to protect open lesions 1
• Do not soak feet in footbaths, as this induces skin maceration and worsens open sores 1

Warning Signs Requiring Urgent Medical Attention

Seek immediate medical care if any of the following develop:

Neurological Complications

• Altered consciousness or impaired mental status 5
• Severe headache with neck stiffness (suggesting meningitis) 3, 6
• Limb weakness or paralysis 5
• Ptosis (drooping eyelids) 5
• Seizures or altered behavior 6

These neurological complications, while rare in adults, can indicate encephalitis, meningitis, or encephalomyelitis, particularly with Enterovirus 71 infections 5, 6

Severe Systemic Symptoms

• Persistent high fever beyond 3-4 days 6
• Signs of dehydration (decreased urination, dizziness, dry mucous membranes) due to inability to maintain oral intake 1
• Respiratory symptoms including difficulty breathing or rapid breathing 6
• Chest pain or palpitations (suggesting potential myocarditis) 3

Secondary Infection

• Increased redness, warmth, or purulent drainage from skin lesions 1
• Worsening pain or swelling around lesions 1
• Red streaking from lesions (suggesting lymphangitis) 1

Follow-Up and Monitoring

• Reassess after 2 weeks if lesions are not improving with standard care 1
• Re-evaluate after 4 weeks if evidence of infection has not resolved and consider alternative diagnoses 1
• Monitor for late manifestations including Beau's lines (nail grooves appearing 1-2 months after fever onset) and periungual desquamation (beginning 2-3 weeks after onset) 1

Infection Control and Prevention

To prevent transmission to others:

• Practice meticulous hand hygiene with soap and water (more effective than alcohol-based sanitizers alone) 1, 7
• Avoid close contact with others until fever resolves and mouth sores heal 1
• Do not share utensils, cups, or food 7
• Clean and disinfect contaminated surfaces regularly, as the virus remains viable on objects for hours 7
• Avoid direct contact with vesicle fluid, which contains extremely high viral loads 7

Special Considerations

Immunocompromised patients may experience more severe disease and require closer monitoring, though HFMD can affect healthy immunocompetent adults with significant symptoms 1, 3, 8

Coxsackievirus A6 is increasingly recognized as causing more severe HFMD in adults with atypical presentations, including widespread vesiculobullous lesions and delayed-onset nail dystrophy 4, 8

Common Pitfalls to Avoid

• Do not routinely use topical antiseptic or antimicrobial dressings for HFMD foot lesions, as these are not recommended for wound healing 1
• Do not confuse with herpes simplex virus infection, which has available antiviral treatment options, whereas HFMD does not 1
• Do not overlook the possibility of severe complications simply because the patient is an adult; neurological complications, though rare, can occur in immunocompetent adults 5
• Do not rely solely on alcohol-based hand sanitizers for prevention; soap and water handwashing is more effective 1, 7