Ondansetron*

• Ondansetron

• Zofran

Classification:

• Antiemetic, serotonin 5-HT3 receptor antagonist

Mechanism of Action:

• Affects both peripheral and central nerves
• Reduces the activity of the vagus nerve, which deactivates the vomiting center in the medulla oblongata
• Blocks serotonin receptors in the chemoreceptor trigger zone
• Has no effect on dopamine receptors and therefore does not cause extrapyramidal symptoms

Indications:

• Chemotherapy-induced nausea and vomiting
• Nausea and vomiting

Contraindications:

• Hypersensitivity
• Prolonged QTc

Adverse Effects:

• Headache
• Dizziness
• Constipation
• Diarrhea
• Blurred vision

Dose:

Adult:

• 4.0 mg IV/IO slow IVP over 2 minutes, may repeat once after 10 minutes
• 4.0 mg IM, may repeat once after 10 minutes
  

Pediatric:

• 0.1 mg/kg IV/IM/IO to max of 4.0 mg, only once

• IV, IO, IM

• Norepinephrine must be given through an infusion pump.
• Most shock states require fluid administration prior to vasopressors therefore normal saline should be initiated prior to norepinephrine administration.
• It is recommended to administer a normal saline infusion by gravity with any norepinephrine infusion. To do this:
  • Initiate a normal saline infusion at a rate appropriate to patient condition via gravity (i.e., not through the pump)
  • Connect the norepinephrine infusion (via the pump) to the access port of the normal saline infusion line proximal to the patient
  • This will help as a driver when volumes of medication being infused are small
• Focus on fluid administration in patients with hypovolemic shock.
• Epinephrine is the vasopressor of choice within the EHS ground ambulance system for pediatric patients ≤ 16 years of age.
• May cause fetal anoxia when used in pregnancy.
• Pregnancy category D [potential benefits may warrant use of the drug in pregnant women despite potential risks (e.g., if it is required in a life-threatening situation)]

• Compendium of Pharmaceuticals and Specialties (CPS)
• Pharmacology for the Prehospital Provider 2nd Edition