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With the approach of summer come some prob-lems you will be seeing in your outpatient practice.

SunburnTopical sunscreens contain a variety of chemicals.1

Chemical sunscreens include benzophenones(oxybenxone, sulisobenzone, dioxybenzone) andother substances (methyl anthranilate, butylmethoxydibenzoylmethane [avobenzone]).Inorganic physical sunscreens are zinc oxide andtitanium dioxide. Products should protect againstboth UVB and UVA radiation.

The sun protection factor (SPF) is a measure ofthe strength of protection.2 It is the theoreticalnumber of hours required to produce redness. It isideal if used perfectly; however, most people donot use enough or do not reapply frequentlyenough. It is recommended that everyone shouldwear sunscreen with a minimum of 30 SPF whileoutdoors. It should be reapplied every 2 hours andevery hour if swimming or perspiring. Using a sun-screen with the insect repellent DEET (diethyltolu-amide) decreases the SPF.

Resistance to removal of sunscreen is called sub-stantivity.3 Water resistant means the effect lasts for40 minutes of water exposure. Very water resistantmeans the product will be effective for 80 minutesof water immersion. Toweling can remove up to85% of sunscreen. A product can be labeled sweatresistant if it is water resistant. Durability is greaterfor water resistant sunscreens than regular sun-screens. Because some products need to dry toresist removal by water, it is prudent to wait 15 min-utes after application before going into the water.

Treatment of mild sunburn can usually be man-aged with cool compresses and various over-the-counter first-aid products. More severe sunburn

may require a medium-potency topical steroid,such as triamcinolone 0.1% twice daily.Nonsteroidal anti-inflammatory drugs can help painand inflammation. Severe sunburn may require oralcorticosteroids, such as prednisone 40 to 60 mgevery day tapered over 7 to 10 days. For example,60 mg for 4 days, 40 mg for 2 days, 20 mg for 2days, then 10 mg for 2 days.

Insect and Tick RepellentDEET is the gold standard insect repellent.4 It iseffective against the largest variety of insects—mosquitoes, chiggers, ticks, fleas, and biting flies.

In general, the higher concentration, the longer therepellent lasts. Recommended strengths are listedin Table 1.

GGeettttiinngg RReeaaddyy ffoorr

Summer Woes

Table 1. DEET Strength

Condition Strength

Children 10% or less

Most conditions 10%-35%

Extreme conditions Greater than 35%

PRESCRIPTION PAD

Maren Mayhew

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Long-acting formulations of DEET were originallydeveloped for the US military. Ultrathon5 is manu-factured by 3M and is available through TravelMedicine, Inc. It comes in two strengths, 25% and33%, and provides 95% protection for 6 to 12hours.

There has been much controversy about the toxi-city of DEET, especially with children. Proper usageshould avoid toxicity. Avoid prolonged use and con-centrations more than 50%. DEET can damageclothes, glass frames, and watch crystals.

Citronella products, including the Avon productSkin-So-Soft Bug Guard (0.10% citronella), are lesseffective than DEET, work only against mosquitoes,and last about 1 hour. Citronella candles are notmuch better than plain candles at repelling insects.

Other botanical products such as oils from soy-bean, geranium, coconut oil, and lemon eucalyptusare used, often in combination. Data are limited onthese products, but they seem to be mildly effec-tive, somewhat less than DEET 7%.

Permethrin is a contact insecticide that is effec-tive against mosquitoes, flies, ticks, fleas, lice,and chiggers. It should be applied to clothing andother fabrics and not to skin. A combination of aDEET repellent and permethrin on clothing is veryeffective.

Picaridin6 is an insect repellent recently intro-duced in the Untied States that has been usedoverseas for years. It is effective against mosqui-toes and ticks. It is available as Cutter Advancedin a 7% solution. Higher concentrations (20%) areused overseas. No incidents of toxicity have beendocumented. It has many advantages over DEETin that it is odorless, not greasy, less irritating tothe skin, and does not damage fabric or plastics. Itlasts 3 to 4 hours. The Centers for Disease

Control and Prevention recommends it as an alter-native to DEET.

Lyme DiseaseLyme disease is caused by the spirochete Borreliaburgdorferi, which is transmitted to humans bythe Ixodes scapularis tick (deer tick).7 Preventionconsists of avoiding ticks. The repellents mosteffective against ticks are DEET, picaridin, or per-methrin on clothing. See the section on insect andtick repellents.

The vaccine for prevention is no longer avail-able. Prophylaxis of a tick bite is controversial. Itmay be advisable if it occurs in an endemic areawhen an engorged I scapularis tick has beenattached for 48 hours or more. Doxycycline 200mg once and amoxicillin 500 mg every 8 hours for10 days have been used.

The diagnosis of Lyme disease is difficult,especially in the early stages. About 70% to 80%of patients infected develop erythema migrans,the diagnostic skin lesion. It is important to starttreatment as early as possible, before the dis-semination of the spirochete. The current aggres-sive pressure to begin treatment for Lyme dis-ease as soon as possible may mean that unnec-essary treatment is started for some patientswho turn out not to have Lyme disease.8

Laboratory tests will confirm the diagnosis, butmany clinicians do not feel comfortable waitingfor the test results. IgG antibodies to B burgdor-feri are usually detectable 4 to 6 weeks after ini-tial infection.

The recommended antibiotic treatments areshown in Table 2. Length of therapy has not beenestablished by scientific research, but mostexperts recommend 2 to 3 weeks of treatment.

Table 2. Treatment of Early Lyme Disease

Antibiotic Dose Frequency Duration

First Line

Doxycycline* 100 mg po q 12 h 21 days

Amoxicillin 500 mg q 8 h 21 days

Cefuroxime axetil 500 mg po q 12 h 21 days

Second Line

Erythromycin 250-500 mg po q 6 h 21 days

Azithromycin 500 mg q d 7 days

*Do not use doxycycline in children younger than 8 years.

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Poison IvyPoison ivy allergic contact dermatitis is caused bycontact with the rhus oleoresin from the poison ivyplant.9 Patients may also develop the allergythrough secondary contact, as in touching some-thing that recently touched the plant.

Prevention is important. Washing the skin withsoap inactivates and removes the oleoresin.Washing must be done immediately. It is 50%effective after 10 minutes, 10% effective after 30minutes, and ineffective after 60 minutes. A barriercream of an organoclay compound (Ivy Block),applied before exposure, is 50% effective.

Treatment begins with topical corticosteroids,cold compresses, and calamine lotion. Topicalsteroids, mild to medium strength, can help the ery-thema. They are not absorbed through blisters.Short, cool tub baths with colloidal oatmeal(Aveeno) can be soothing. Calamine lotion canexcessively dry the skin. Oral hydroxyzine or diphen-hydramine control itching and help with sleep.

For severe cases, oral prednisone may be need-ed. Do not use the standard Dosepaks, becausethey do not contain sufficient prednisone. Onemust use enough initially and as soon as possible,then taper to avoid a rebound. Use prednisone 60mg for 4 days, 50 mg for 2 days, 40 mg for 2 days,30 mg for 2 days, 20 mg for 2 days, then 10 mgfor 2 days.

References

1. Rakel RE, Bope ET. Conn’s current therapy. 57th ed. Philadelphia:Saunders; 2005. p. 1002.

2. Prevention and treatment of sunburn. Med Lett. 2004;46(1184):45-46.

3. Poh Agin P. Water resistance and extended wear sunscreens.Dermatol Clin. 2006;24(1):75-79.

4. Auerbach PS. Wilderness medicine. 4th ed. St. Louis: Mosby; 2001.p. 759-766.

5. Insect repellents. Med Lett. 2003;45(1157):41-42.6. Picardin: a new insect repellent. Med Lett. 2005;47(1210):46-47.7. Treatment of Lyme disease. Med Lett. 2005;47(1209):41-43.8. Cohen J, Powderly WG. Infectious diseases. 2nd ed. St. Louis:

Mosby; 2004. p. 599-600.9. Habif TP. Clinical dermatology. 4th ed. St. Louis: Mosby; 2004.

p. 88-89.

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into this regulatory scheme. The vision statementcan be downloaded from the National Associationof Clinical Nurse Specialists web site atwww.nacns.org.

Here are some recommendations for NPs wholike to plan ahead.

• If you want input into decisions being made,apply for positions on your state’s board ofnursing.

• Unless you have extensive experience in aspecialty area as a registered nurse, do notseek or take jobs that are outside of your areaof certification. Aside from potential hassles ingetting your written agreement through theboard, you may be exposing yourself to mal-practice liability.

• If certification is available in the specialty inwhich you are working and you like your work,go get the certification. Do not wait for a ruleto come down that puts you out of a job.

• If you think you want to practice in a special-ty area, get the certification. If no certifica-tion is available, understand that, if you takethe job, you will be in a precarious position ina health profession that already is in a precar-ious position. Cover your bases by puttingevery procedure you will perform in yourwritten agreement and on your applicationfor malpractice insurance.

1555-4155/06/$ see front matter© 2006 Elsevier Inc. All rights reserved.doi:10.1016/j.nurpra.2006.03.009

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Maren Mayhew, MS, ANP, GNP, is the author and editor ofPharmacology for Primary Care Providers, a textbook forNPs published by Mosby. She can be reached at marenmayhew@comcast.net. This is a monthly column on med-ication news and controversies. Suggestions for topics arewelcome.

Carolyn Buppert, CRNP, JD, practices law in Annapolis, MD.She can be reached at cbuppert@buppert.com.

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