Insect Bites & Stings Flashcards
1
Q
What happens when you get a spider bite
A
- venom is injected with bite
- most spiders are venomous, but few deliver enough for systemic symptoms
- venom from some is neurotoxic (widow spiders) to cytotoxic (reclusive spiders)
2
Q
what happens when you get a tick bite
A
- attaches and feeds until engorded with blood
- can attach to any part of body, but most often in warm areas that may be dificult to see (armpits, groin, scalp)
- may also attach to pets
*deer tick can cause lyme disease if attached for more than 36-48H
- others carry rocky mountain spotted fever and can transmit if attached fro 4-6 horus
3
Q
what happens when bitten by mosquito
A
- females inset tip of mouth into small bleed vessels near surface of skin and inj salivary secretions that cause local histamine reactions
- mosquitoes can carry number of viral and parasitic diseaess that may be transmitted when they bite
4
Q
what happens upon bee or wasp sting
A
- injected with venom
- honey bees can onyl sting once, bumble and vesipids (wasps) can string multiple times
- venom contains multiple proteins that can cause a severe reaction
5
Q
presentation of a spider bite
A
- Common reaction
- itintial stinging then localized swelling, itching and inflammatio
- More severe raction
- if black widow bite: pain within 30-60 min followed by sweating, nausea, blurred vision and muscle cramps
- Brown reculse bite; redness, itching and pain within 6 hours; tissue necrosis if left untreated
6
Q
presentation of tick bite
A
- common presentation
- red papule at bite site
- swelling, blistering, bruising or itching may occur
- red papule at bite site
- More severe reactions
- Lyme disease
- 3-30 days after bite -> erythema migrans rash that begins at bite site and expands gradually
- flu like symptoms (fever, HA, fatigue, muscle and joitn aches, swollen lymph nodes etc)
- Days to months after bite: severe headaches, facial palsy, severe joint pain, heart palpitations, inflammation of brain spainal chord
- Rocky mountain spotted fever
- Day 1-4: fever, headache, nausea and vomiting, myalia, rash 2-4 days after onset
- Day 5+ altered mental status, coma ,acute resp distress
- Lyme disease
7
Q
presentation of mosquito bite
A
- common
- rad, itchy papule that develops within hours and subsides voer a few days
- More severe
- if develop antibodyies: large welts that last several days
- West nile virus
- flue like symptoms (fever, headache, body aches, swollen lymph nodes); possible rash
- severe illness: high fever, stiff neck, confusion, muscle weakness or degeneration
8
Q
presentation of Bee or Vespid sting
A
- common
- pain, redness and swelling at site within 4-48 horus
- severe
- extensive local reaction: swelling over a large area (ie whole limb) that peaks at 48 hours and subsides over 3-10 days
- systemic reaction: headache, fever, nausea, vomiting etc wtihin 12-24 hours
- anaphylaxis: trouble breathing or swallowing, swelling of lips or throat, rapid HR
9
Q
red flags for insect bites
A
- sigsn fo anaphylactic reaction (trouble breathing or swallowing, swelling of lips or throat, rapid HR)
- experiencing a severe local rxn (significant paind and swelling beyond initial lesion) -> >10cm in diameter or history of severe rxn
- sting on tongue or mouth, or multiple stings
- bullseye appearance around lesion or appears infected (fever, pus or unusual swelling, redness or tenderness)
- immunocompromised
- lesion has persisted for >7days and not improving after 24h of treatment
10
Q
Non pharm strategies to manage insect bites
A
- remove the insect/stringer to decrease local reactoin
- if tick, use tweezers and gasp close to head
- remove stinger by gently scraping side with tweezers,ignernail or credit card
- do not pull, can force more venom into skin
- clean bite with soap and warm water
- ice or cool to provide symptomatic relief and reduce swelling
- home remedies (oatmeal, baking soda baths, toothpaste, salat/vinegar) may relieve symptoms but are not well studies
11
Q
treating bug bites/stings with oral antihistamines
A
- recommend at self case dose to reduce itching, swelling and redness
- may be mroe effective than topical products in reducing pain, itching and ifnlammation associated with stings
- first and second generation are qually effective
- second gen less sedating and longer acting
- avoid topical antihistamines due to risk of contact dermatitis
12
Q
oral analgestics for tick bites/stings
A
can be recommended at usual self care doses to decrease pain
13
Q
tpoical hydrocortisone for treatment of bites/stings
A
- can be applied up to QID for max 7 days to reduce itching, swelling and redness
- Topical hydrocortisone 0.5-1% is available without a prescription in Canada
- pharmacists may prescribe hydrocortisone 0.5-1%, but studies on efficacy are limited
- once or twice daily application of topical hydrocortisone may be as effective as TID or QID
- use cautiously on areas on broken skin and aovid if signs of infection
14
Q
what other products (besides hydrocortisone) are used for bites/stings
A
topical orudcts w/ local anesthetics:benzocains, pramoxine),
- astringents (calamine)
- counter irritants (menthol)
or ammonia/baking soda
*may get some relief but efficacy aidence is lacking
- in some patients may worsen symptoms due to irritation
15
Q
treatment of bties/stings with oral corticosteroids
A
- can be used for severe local reactions (prednisone 1 mg/kg (up to 50 mg) daily F5-7D
- pharmacists cant prescribe for this, so would need to reffer
