Pharm - Epi Pens

Question 1

Describe a type 1 hypersensitivity reaction

Answer 1

• immediate
• IgE mediated
• IgE abs formed after drug exposure occupy receptors on surface of mast cells/basophils. If drug encountered again, it binds IgE abs and causes release of vasoactive mediators which cause the sx

Question 2

common meds that cause type 1 rxns

Answer 2

• beta lactams

- quinolones

Question 3

mechanism of action of epinephrine for a type 1 hypersensitivity reaction

Answer 3

• Acts as α-1 receptors to mediate increased vasoconstriction, increased peripheral vascular resistance, and decreased mucosal edema.
• Agonist effect at β-2 receptors result in bronchodilation and decreased mediator release from mast cells and basophils

Question 4

active drug in the EpiPen

Answer 4

…… epinephrine …… :)

Question 5

EpiPen concentration

Answer 5

0.3 mg per dose

Question 6

EpiPen dosage

Answer 6

• Adult: autoinjectors with 0.3 mg/dose
• Large/obese adults: have access to at least 2 doses
• Children: 0.01 mg/kg, up to 0.3 mg
• Small children: 0.15 mg dose for kids between 10-25kg and 0.3 mg dose for those >25kg
• Infants/toddlers: 0.1mg available→for infants/toddlers 7.5-15kg

Question 7

ADRs associated w/ the use of epi autoinjectors

Answer 7

• tremor, dizziness, palps, anxiety, restlessness, HA

- serious ADR: myocardial ischemia after injection

Question 8

Describe the correct use of an epinephrine autoinjector

Answer 8

• grip pen firmly and remove safety cap
• swing and push pen into middle of outer thigh at 90 degree angle
• keep pen pressed firmly against thigh for 10 s
• remove pen and massage injection area
• after use: get emergency help; make sure 2nd dose is close; take an antihistamine

Question 9

indications for use of EpiPen

Answer 9

• trouble breathing
• tightness in the throat
• lightheaded or think they might pass out
• not responding as expected/has altered consciousness during allergic reaction
• has food allergies and is vomiting repeatedly shortly after eating (esp if accompanied by flushing/hives)
• coughing repeatedly during allergic reaction
• previous anaphylaxis and develops widespread hives after suspected/known ingestion of an allergen
• has definitely eaten a trigger food that previously caused severe anaphylaxis (can use before symptoms in this case)

Question 10

patient education for EpiPen use

Answer 10

• IM injection is preferred
• hold w/ closed fist
• children may not hold still so hold their leg firmly in place and for 3 or more seconds after
• stay with other people during reaction

Question 11

emergency department use of EpiPen

Answer 11

• if alone, self administer EpiPen then call for help to be transported to nearest ED ASAP **important to educate pt that the use of the EpiPen isn’t what’s dangerous, rather the reaction itself
• even if the ED is close and EMTs on the way, still admin Epi
• if pt becomes light headed, lie down and elevate legs
• pt should never be propped up during anaphylaxis (empty ventricle syndrome)
• transport to ED in supine position

Question 12

pt education for replacement of of EpiPens

Answer 12

• should replace annually
• inform pt it’s better to use out-of-date pen than to use nothing
• store in locations w/ neutral temps (heat is the worst on them)

Question 13

explain the FDAs decision to allow the use of EpiPens beyond expiration date

Answer 13

• FDA says certain EpiPens made b/w April-Dec 2018 can be used for an additional 4 mos to help ease shortages
• study showed devices as much as 4 yrs out of date still contained 84-88% of intended dose