Allergy / Anaphylaxis

Question 1

Diphenhydramine / Benadryl

Answer 1

Class:
Antihistamine

MOA:
noncompetitive histamine H1 receptor antagonist used to treat allergic reactions

Indications:
allergic reactions, dystonic reactions

Contraindications:
neonates, infants, pregnant women, nursing mothers, hypersensitivity, cardiac history asthma (thickens bronchial secretions)

Side effects:
can cause CNS depression, potentiates other CNS depressants (including alcohol, narcotics), Sedation, hypotension, drowsiness, loss of coordination, dry nose, mouth and throat, upset stomach

Dosage:
Adult 25 to 50 mg SIVP, IM, PO

Ped 1-2mg/kg SIVP/IO/IM

Question 2

Epinephrine

Answer 2

Class:
Adrenergic, sympathomimetic

MOA:
stimulates Alpha 1, and Beta 1 & 2 receptors

increases chronotropy, dromotropy, inotropy, automaticity

competetive histamines antagonist relaxes smooth bronchial muscles reversing anaphylaxis

Indication:
refractory asthma
anaphylaxis
bradycardia w/ hypotension
cardiac arrest 

Contraindication
Hypersensitivity, hemorrhagic shock, hypovolemic shock, Pre Existing tachydysrhythmia, hypertension, active labor

Side effect:
Anxiety, nervousness, palpitations, fear, sweating, headache, nausea, vomiting, pale skin, shortness of breath, dizziness, weakness, tremors

Untoward effect:
hypertension, a-fib, chest pain, blurred vision, confusion, seizures

Caution:
Injection into the wrong area can cause gangrene and tissue necrosis

Dosage:
Refractory asthma, Anaphylaxis 0.3mg- 0.5 mg (1:1000) IM

Bradycardia, profound hypotension 0.05- 0.1 mg (1:10000) SIVP

Cardiac arrest 1 mg (1:10000) IV/IO every 3-5 minutes

Post arrest infusion 0.1- 0.5 mcg/kg/min with a max of 30 mcg/min mix 1 mg in 250 ml

Ett 2- 2.5 mcg diluted in 10 ml normal saline

Question 3

Baycadron / Dexamethasone
Deltasone / Prednisone
Solu-Cortef / Hydrocortisone
Solu-Medrol / Methylperdnisolone

Answer 3

Classification
Steroid

MOA
Suppresses acute & chronic inflammation. Reverses capillary permeability & potentiates smooth muscle relaxation.

Indication
Bronchospasms, anaphylaxis, croup (laryngotracheobronchitis)

Contraindication
chicken pox, Hypertension, seizure, thrombocytopenia (low platelet count), Hypersensitivity to sulfa, Fungal infection(due to steroids lowering immune system), Cushioning syndrome (which is high levels of cortisol & steroids are synthetic cortisol), CHF (adrenal steroid hormone is responsible for conservation of sodium in the kidneys, and increased elimination of potassium. Reabsorption of sodium leads to a proportionately greater retention of water, and the excess fluid is stored primarily in the interstitial and intravascular spaces. Gradual overfilling of the interstitial compartments produces edema. Excess of fluid in the intravascular spaces acts as a distending force which, like over-transfusion, results in elevation of blood pressure and cardiac enlargement)

Onset time: 1 - 2 hours

Cautions: pregnancy class C crosses placenta can cause fetal harm

Dosage
Allergic reaction 4-10 mg IV/IM

Baycadron / Dexamethasone Asthma 0.6-1 mg/kg

Deltasone / Prednisone 5-60mg PO

Solu-Cortef / Hydrocortisone 100mg IV,IM,IO

Solu-Medrol / Methylperdniolose 125 mg IV,IM,IO / Pediatric 1 - 2mg/kg IV/IM/IO (max dose 125mg)