Head Lice

Head Lice

OVERVIEW:

Lice, or pediculosis, is an infestation by parasites that feed on human blood. A mature female louse lays eggs, or nits, which appear as small white spots cemented to the base of hair. Lice may infest head, body, or pubic hair.

SIGNS AND SYMPTOMS:

• Head lice (pediculosis capitis):
• Found most often on the back of the head and neck and behind the ears
• Nits are white spots on hair shaft that cannot be moved. Itching
• Prickling sensation of the scalp
• Eyelashes may be involved
• Body lice (pediculosis corporis):
• Affects individuals with poor hygiene
• Adult lice live and lay their nits in the seams of clothing.
• Most common symptom is itching that leads to scratching and infection.
• Uninfected bites appear as red spots.
• Pubic lice (phthirus pubis):
• Itching of groin and rectal area
• May have no symptoms during 30-day incubation period
• Delay in treatment may lead to development of widespread groin inflammation and infection.
• Pubic hair is the most common site.
• Lice may spread to hair around rectum, abdomen, armpit, chest, beard, eyebrows, and eyelashes.
• Infested adult patients may spread lice to eyelashes of children.

CAUSES:

Lice are transmitted by close personal contact and contact with objects such as combs, hats, clothing, and bed linen.

SCOPE:

Head lice affects 10-40% of students in schools where accurate surveys have been conducted.

MOST OFTEN AFFECTED:

• Most common in adults: pubic lice
• Most common in children: head lice
• More common in females than males

RISK FACTORS:

• Body lice: inability to change and launder clothing, overcrowded sleeping quarters
• Pubic lice: sexual contact with an infected person

DIAGNOSIS

PHYSICAL EXAMINATION:

The Physician will perform a physical examination to identify lice and nits.

TESTS AND PROCEDURES:

N/A

TREATMENT

GENERAL MEASURES:

• After treatment with shampoo or lotion, nits remain in scalp or pubic hair.
• Nits are best removed with a very fine comb (nit comb). Removal may be made easier by soaking the hair in a solution of equal parts water and white vinegar and wrapping wet scalp in a towel for at least 15 minutes.
• Repeat treatment periodically as needed for stubborn nits.
• All family contacts possibly infested with head lice should be treated at the same time.

ACTIVITY:

No restrictions

DIET:

No special diet

MEDICATIONS

COMMONLY PRESCRIBED DRUGS:

• Lindane (Kwell)
• Pyrethrins-piperonyl butoxide (Rid)
• Permethrin (Nix)
• Eyelash infestation: careful manual removal of lice and nits or application of petroleum jelly (Vaseline) 3 or 4 times a day for 8 to 10 days

CONTRAINDICATIONS:

Avoid lindane in infants and pregnant women.

PRECAUTIONS:

• Medication should never be used to treat eyelash infections.
• Accidental ingestion and gross overuse of lindane may be associated with central nervous system toxicity.

DRUG INTERACTIONS:

N/A

Other Drugs:

Malathion (Ovide)

FOLLOW UP

PATIENT MONITORING:

As needed

PREVENTION/AVOIDANCE:

• Changing and laundering clothing eliminates risk of head lice.
• Careful followup in schools by public health nurses may help prevent recurrence and spread of head lice.
• Washing combs, brushes, hats, coats, collars, sheets, pillow cases, etc., will help to prevent re-infestation.

COMPLICATIONS:

WHAT TO EXPECT:

• With appropriate treatment, the cure rate is over 90%.
• Recurrence is common, mainly from reinfection and failure to comply with treatment.

MISCELLANEOUS

OTHER FACTORS:

N/A

PEDIATRIC:

N/A

GERIATRIC:

N/A

OTHERS:

N/A

PREGNANCY:

N/A

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Medical Diagnosis » H » Head Lice