Treatment of Scabies in a 70-Year-Old Patient
Treat with permethrin 5% cream applied to all areas of the body from the neck down (and including the scalp, temple, and forehead in elderly patients) and washed off after 8-14 hours. 1, 2, 3
First-Line Treatment Approach
Permethrin 5% cream is the gold standard first-line treatment for scabies in a 70-year-old patient, with approximately 30 grams sufficient for an average adult application. 1, 2, 3, 4
Critical application detail for elderly patients: Unlike standard adult treatment, the scalp, hairline, neck, temple, and forehead should be included in the application area, as elderly patients (like infants) can have head involvement. 3, 5
The cream should remain on the skin for 8-14 hours before washing off with a shower or bath. 1, 2, 3
One application is generally curative, though a second treatment may be considered after 1-2 weeks if live mites are observed or symptoms persist beyond 2 weeks. 1, 2, 3
Alternative Treatment Options
If permethrin fails or is unavailable, consider these alternatives in order of preference:
Oral ivermectin 200 μg/kg body weight, taken with food to increase bioavailability, with a mandatory second dose after 2 weeks to address the limited ovicidal activity. 1, 2
Avoid lindane in this 70-year-old patient due to contraindications in elderly populations, particularly those with extensive dermatitis or potential immunocompromise, given the risk of neurotoxicity and seizures. 1, 2
Sulfur 6% ointment applied nightly for 3 nights can be used as a third-line option. 1
Critical Management Steps Beyond Medication
Treat all household and close personal contacts simultaneously within the preceding month, even if asymptomatic, to prevent reinfection. 1, 2, 6
Decontaminate all bedding, clothing, and towels by machine washing and drying on hot cycle, dry cleaning, or isolating items from body contact for at least 72 hours. 1, 2, 6
Keep fingernails closely trimmed to reduce skin injury from scratching. 1
Follow-Up and Expected Course
Pruritus may persist for up to 2 weeks after successful treatment and is not necessarily a sign of treatment failure—this is a common pitfall leading to unnecessary retreatment. 1, 2, 3
Evaluate at 2 weeks post-treatment if symptoms persist; retreatment is indicated only if live mites are demonstrable after 14 days. 2, 3
Reasons for true treatment failure include inadequate application (missing scalp/head in elderly), failure to treat contacts simultaneously, reinfection from contaminated fomites, or rarely, medication resistance. 1, 2
Special Considerations for This Age Group
Monitor for crusted (Norwegian) scabies if the patient is immunocompromised, debilitated, or malnourished, as elderly patients are at higher risk. 1, 2
If crusted scabies is present, aggressive combination therapy is required: permethrin 5% cream applied daily for 7 days then twice weekly, PLUS oral ivermectin 200 μg/kg on days 1,2,8,9, and 15. 1, 2
Single-application permethrin alone will fail in crusted scabies due to the massive mite burden. 2