Why Over-the-Counter Scabies Treatments May Not Be Effective

Scabies is a skin condition that is most often transmitted by way of sexual or other close contact, though it is less frequently possible for transmission to occur indirectly by way of shared clothing, towels, bedding, etc. Scabies is classified as a parasitic STD (Sexually Transmitted Disease). While there are some non-prescription products that can be used in the treatment of scabies, only prescription remedies have been approved for this purpose.

The actual cause of scabies is a tiny mite of the Sarcoptes scabiei species which burrows into the skin, creating tiny visible red burrow lines. The body's allergic reaction to the mite, its eggs, and its feces causes a rash of red bumps, and a very troubling itch, which can be especially bad at night.

Not uncommonly, people with scabies make the situation even worse by frantically scratching at the area, thereby breaking the skin and potentially leading to secondary infections such as impetigo.

Scabies transmitted through sexual contact usually strikes the genital area, but scabies can also occur elsewhere on the body, including the abdomen, ankles, breasts, buttocks, fingers, thighs, and wrists.

Scabies is one of the more unpleasant things to suffer through, but the good news is that it is a curable condition. The mite and its eggs can usually be killed with a topical pesticide.

The most common substance used in the treatment of scabies is the chemical permethrin. This comes in a cream or lotion form, and is spread over the entire body from the neck down, then washed off after several hours.

Low doses of permethrin are available in over-the-counter products such as Rid and Nix, and some people get good results from these products. However, these products are designed for use against pubic lice (crabs), and, as the Centers for Disease Control and Prevention (CDC) points out, none of these non-prescription remedies has been tested and approved for use against human scabies.

Creams with a higher concentration of permethrin, as well as another chemical treatment called lindane, and a non-chemical treatment that can be used for babies called crotamiton are available by prescription.

A physician can also prescribe an oral medication called ivermectin for severe cases, cases that are not responsive to the lotions and creams, and patients with altered immune systems.

Generally the treatment available by prescription will succeed in eliminating the mites and their eggs, but that does not mean that full relief will be immediate. The itch caused by the allergic reaction of the body can last up to several weeks after the mites are gone.

It is also an important part of treatment to eliminate mites from any items that could cause a reinfestation. All clothes, towels, bedding, etc. should be dry cleaned, or washed in hot water and dried at high heat.

Mites cannot live very long away from a body, so anything that has been free of contact with an infected or possibly infected person for at least 72 hours shouldn't have any mites, though it doesn't hurt to be safe and wash items in hot water if there is any doubt at all.

Sources:

Elizabeth Boskey, "Scabies: An Overview." About.com.
"Scabies." Centers for Disease Control and Prevention.
"Scabies." Mayo Clinic.
"Scabies." STD-gov.org.