| • | it may take a month after any single scabies treatment for all cutaneous signs to resolve |
| • | as of 9/2009 permethrin still the most effective (even better than ivermectin - per Dirk Elston, MD) |
lindane (Kwell)
| • | lotions and creams containing 1% lindane |
| • | only benefit over permethrin is cost |
| • | incidence of adverse reactions is extremely rare |
| • | but there is little doubt that overexposure to lindane products applied topically can cause CNS toxicity, convulsions, and, rarely, death |
| • | cases of lindane resistant scabies have been reported |
| • | mnemonic: can be “lindangerous” |
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permethrin (Elimite)
| • | brand name: Elimite (5% dermal cream) |
| • | MOA – acts on nerve cell membranes of parasites, therefore paralyzing exoskeleton muscles that allow lice to breath |
| • | active against, lice, ticks, mites, and fleas |
| • | it is important that all insecticides are put on dry hair because lice can close down their respiratory airways for one-half hour when immersed in water |
| • | treatment of choice for scabies by most dermatologists; about 90% cure after single treatment |
| • | excellent safety record; approved for infants aged 2 months or older |
| • | unlike lindane, it is rapidly metabolized and does not accumulate in adipose or CNS tissues |
| • | adverse effects limited to local burning, irritation |
| • | mnemonic: Elimite “permets” the treatment of infants and “elimites” (eliminates) the risk of CNS toxicity |
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Babies and pregnant women
| • | 6% to 10% precipitated sulfur in petrolatum applied QHS X 3 nights |
| • | older than 2 months, use permethrin |
| • | 6 week old infant - none "FDA-approved" but treatment of choice is permethrin |
ivermectin
Scabies:
| • | a single 200 µg/kg dose is effective in immunocompetent patients (come as 6mg tablets) |
| • | two doses (one to two weeks apart) for some AIDS patients with crusted scabies (along with topical treatment) |
| • | not approved for use in children under five, not FDA-approved for the treatment of scabies in humans |
| • | lice: a single oral dose 200 µg/kg, repeat in 10 days |
| • | used extensively to control onchocerciasis (Ochocerca volvulus) |
ivermectin (stromectol) (come as 3 or 6mg tablets)
Lice: ivermectin 250 µg/kg single dose
| • | children: <15kg (33lbs) = don’t use ivermectin; 15-24kg (33-53lbs) = 3mg tab X1; 25-35kg (54-77lbs) = 6mg tab X1; >35kg = adult dose |
| • | 35kg (70lbs) = 9mg X1; 48kg (106lbs) = 12mg X1; 60kg (132lbs) = 15mg X1; 72kg (159lbs) = 18mg X1; 84kg (185lbs) = 21mg X1; 96kg (211lbs) = 24mg X1 |
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Environmental Decontamination
| • | scabies is spread by close person to person body contact |
| • | there is little evidence that clothing, bedding etc… play a significant role in the spread of scabies, except in the crusted form (crusts are teeming with mites and viable eggs) |
| • | i.e. no environmental reservoir |
| • | laundering of clothing is considered sufficient |
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