What is the first-line treatment for scabies in a geriatric patient?

First-Line Treatment for Scabies in Geriatric Patients

Permethrin 5% cream is the first-line treatment for scabies in geriatric patients, applied to all areas of the body from the head to the soles of the feet and washed off after 8-14 hours. 1, 2, 3

Treatment Options and Application

• Permethrin 5% cream should be thoroughly massaged into the skin from head to soles of feet, with special attention to the scalp, hairline, neck, temple, and forehead in geriatric patients as these areas may be infested (unlike in younger adults) 3
• Approximately 30 grams of permethrin cream is usually sufficient for an average adult 3
• One application is generally curative, with the cream being removed by washing (shower or bath) after 8-14 hours 3
• Oral ivermectin (200 μg/kg body weight) is an alternative first-line option, especially for patients who may have difficulty with topical application, taken with food to increase bioavailability, with a second dose after 2 weeks 1, 2

Special Considerations for Geriatric Patients

• Geriatric patients are at higher risk for developing crusted (Norwegian) scabies due to immunosuppression from age-related factors, comorbidities, or medications 1, 4
• For crusted scabies in elderly patients, combination therapy is recommended: 5% permethrin cream applied daily for 7 days, then twice weekly until cure, plus oral ivermectin 200 μg/kg on days 1,2,8,9, and 15 1, 2
• While permethrin is metabolized in the liver and excreted in the urine as inactive metabolites, there does not appear to be an increased risk of toxic reactions in elderly patients with impaired renal function when used as labeled 3

Management of Side Effects and Follow-Up

• Patients may experience temporary exacerbation of pruritus, edema, and erythema after treatment with permethrin 3
• Persistent pruritus after treatment is common and may last up to 2-4 weeks; this is rarely a sign of treatment failure and is not an indication for retreatment 3
• Retreatment should only be considered if there are demonstrable living mites after 14 days 3
• Permethrin may be very mildly irritating to the eyes; patients should avoid eye contact during application and flush with water immediately if exposure occurs 3

Environmental and Contact Management

• All bedding and clothing should be decontaminated by machine washing and drying using hot cycle, dry cleaning, or removing from body contact for at least 72 hours 1, 2
• All persons who have had sexual, close personal, or household contact with the patient within the preceding month should be examined and treated simultaneously 1, 2
• For institutional outbreaks (common in nursing homes), treat the entire population at risk and consult with an expert 1, 5

Common Pitfalls to Avoid

• Failure to treat all close contacts simultaneously, which can lead to reinfection 1, 2
• Inadequate application of topical treatments, particularly in geriatric patients who may need assistance with application 1, 2
• Not extending treatment to the scalp and hairline in geriatric patients, as these areas are commonly affected in this population unlike in younger adults 3
• Expecting immediate resolution of symptoms (may take up to 2-4 weeks for pruritus to resolve completely) 1, 2, 3
• Retreating unnecessarily for persistent pruritus in the absence of live mites 3