Insect Bites, Stings, Pediculosis Flashcards
1
Q
Overall, Risk Factors
A
- Mild allergic rxn or systemic allergic rxn (may be life threatening)
Risk Factors: - Being outside! • Occupational exposure • Hiking • Backyard
2
Q
Insect BITES: Exclusions for Self-Treatment
A
- < 2 years of age
- Hypersensitivity (systemic sx or sx distant from bite)
- Hx of tick bite and systemic effects indicating infection
- Suspected spider bite (black widow or brown recluse)
- Signs of secondary infection bite area
- Scabies (ie, itching between webbing of fingers)
3
Q
Insect STINGS: Exclusions for Self-Treatment
A
- <2 years of age
- Allergic reactions: hives, excessive swelling, dizziness, weakness, nausea, vomiting, difficulty breathing
- Significant allergic response away from site of sting
- Previous sting by honeybee, wasp, or hornet (must evaluate possible development of hypersensitivity)
- Previous severe reaction to insect bites
- Personal or family history of significant allergic reactions
- Symptoms after 7 days of self-treatment
4
Q
General Treatment Approach to Bites
A
- Apply ice pack in washcloth up to 10 min with 10 min between applications
- Apply topical analgesic to the site
- Avoid scratching!
- Seek medical attention if worsens or sx persist after 7 days of treatment
- Prevent future bites (cover skin, avoid swamps/woods, pest-free pets, barriers, limit time outside)
5
Q
General Treatment Approach to Stings
A
- Remove stinger ASAP
- Apply ice pack in 10 minute intervals
- Apply local anesthetic, skin protectant, antiseptic, topical antihistamine or corticosteroid, or counter-irritant
*Note: labeling of products only mentions “insect bites”; accepted that FDA intends this includes stings
6
Q
N, n-diethyl-m-toluamide 4-100%, DEET
A
- In most products - BEST repellant!
- Releases vapors that discourage insect approach
• Duration varies with concentration (10% ~ 2 hrs, 30% ~ 5 hrs)
- Adults: 10-35% (≥20% to repel ticks; >50% may have longer duration and adverse skin reactions)
- Children: <30% (avoid in <2 months old)
- Apply no more than every 4-8 hours
- Skin irritation is most frequent problem
- Toxic if ingested internally
- Safe for pregnant and breast-feeding moms
7
Q
DEET Safety Counseling
A
- Do not allow children <10 years old to apply to themselves
- Do not apply to young children’s hands or near eyes/mouth
- Do not breathe in, swallow, or get into eyes
- Do not put on wounds or broken skin
- Use just enough to cover exposed skin/clothing
- Do not use under clothing
- Do not spray in enclosed areas
- To apply to face, spray on hands first and then rub on
- Apply sunscreen FIRST and wash hands after applying DEET
- After returning indoors, wash treated skin (soap and water)
- Wash treated clothing before wearing again
8
Q
Pharmacologic Therapy
A
- Not approved for <2 years old
- Consider patient preference and dosage form
- Prolonged use can lead to hypersensitivity
- Max use 7 days for all
9
Q
Local Anesthetics
A
Benzocaine, Lidocaine
- For relief of itching and irritation d/t insect bites
- MOA: reversible blockade of nerve impulses (loss of sensation)
- Apply to bite area up to 3-4x/day, max 7 days
- Relatively nontoxic (may cause allergic contact dermatitis)
- Avoid phenol in pregnant women and children
- Sensitization can occur
10
Q
Topical Antihistamines
A
- Diphenhydramine (0.5-2%) in most products
- MOA: anesthetic effect by depressing cutaneous receptors
- For temporary relief of pain/itching d/t to minor bites
- Apply to bite area up to 3-4x/day, max 7 days
- Not absorbed sufficiently to cause systemic side effects
- Can cause photosensitivity and hypersensitivity reactions
11
Q
Counterirritants
A
• MOA: at low concentrations, depress cutaneous receptors, thereby causing analgesia and anesthesia
• Camphor (0.1-3%)
- Very dangerous if ingested (keep away from children)
• Menthol (0.1-1%)
- Considered safe and effective antipruritic
• Apply to bite 3-4x daily, max 7 days
12
Q
Hydrocortisone (contra)
A
- 1% topical preparations for temporary relief
- Wide variety of dosage forms available
- Apply to bite area 3-4x/day for up to 7 days
• Adverse effects with prolonged use
- Skin atrophy, acneiform eruptions, irritation, folliculitis, skin tightening/cracking
- Can worsen or mask infections
• Contraindications
- Scabies, fungal, or bacterial infections
13
Q
Skin Protectants
A
- Act as protectants, reduce inflammation and irritation
- Zinc oxide and calamine
- Zinc oxide is a mild astringent and weak antiseptic
- Both absorb fluids from weeping lesions
- Both safe and effective at conc. 1%-25%
• Titanium dioxide
- Safety and efficacy not determined by FDA
- Apply as needed to affected area 3-4x/day, max 7 days
- Minimal adverse effects; ok for adults, children, and infants
14
Q
Patient Counseling
A
• To prevent stings
- Avoid perfume, scented lotions, and brightly colored clothes
- Control odors in picnic and garbage
- Wear shoes when outdoors
- Destroy nests of stinging insects near home
- Change children’s clothing if contaminated with fruit
- Do not scratch affected areas; keep fingernails trimmed
- If hypersensitive to stings, wear bracelet or carry card
- If allergic sx occur, administer emergency treatment (epi, oral ah) and seek immediate medical attention
- Seek medical attention if sx worsen or persist after 7 days of treatment or if sx of secondary infection or fever
15
Q
Emergency Treatment of Allergic Reactions
A
- If allergic: hives, itching, swelling, burning of skin
- Anaphylaxis is rare
- Epinephrine drug of choice for anaphylaxis
- Systemic antihistamines and corticosteroids used together
- If allergic to stinging insects, should ALWAYS carry epinephrine
