Infusion Reaction (HSR/Allergic) Guide

Reaction Management Flowchart

STOP Infusion
Vitals q5 min
Call Responding Provider / Activate Emergency Response

Stay with the patient; monitor continuously (including SpO₂). Document all actions in HSR/Allergy orders and as an Observed ADR.

Step 1 — First Signs of Reaction

Immediate Actions

  • STOP infusion now.
  • Monitor vitals every 5 minutes and continuous SpO₂.
  • Notify Responding Provider and activate your area’s emergency response process.
Step 2 — Identify Symptoms

Classify Presentation

  • Mild Hives (urticaria), rash, itching, and/or facial flushing.
  • Moderate Fever/chills/rigors (Fever: > 38.3°C OR ≥ 38°C for ≥ 1 hour).
  • Severe Hypotension (SBP < 90 mmHg or ↓ > 20 mmHg), wheeze/shortness of breath, facial/lip/tongue swelling.
Hypotension definition: SBP < 90 mmHg or drop > 20 mmHg from baseline.
Step 3A — Mild: Hives / Rash / Itching / Flushing

Antihistamine Pathway

  • If NO diphenhydramine premed OR it was given > 30 minutes prior to reaction:
    Diphenhydramine 50 mg IV push over 2 minutes.
  • If diphenhydramine premed was within 30 minutes:
    Diphenhydramine 50 mg IV push over 2 minutes and Cetirizine 10 mg PO.
Reassess after 5 minutes. If improving, continue monitoring and follow provider instructions. If not improving, proceed to Step 3B.
Step 3B — Fever / Chills / Rigors

Antipyretic & Notify

  • Acetaminophen 1,000 mg PO x 1 dose.
  • Notify Responding Provider for additional instructions (consider special pathways for SCT patients).
Step 3C — Persistent / Escalating (Allergy Pathway)

If symptoms persist or escalate after initial therapy

  • Hydrocortisone 100 mg IV push over 1 minute, then
  • Repeat Diphenhydramine 50 mg IV push over 2 minutes, and
  • Cetirizine 10 mg PO (if not already given).
Note: Some chemo/biotherapy agents advise avoiding corticosteroids; however, steroids should still be given in severe allergic reactions.
Step 3D — Severe / Suspected Anaphylaxis

Immediate Emergency Management

  • STOP infusion.
  • O₂ 2 L/min via nasal cannula if SpO₂ ≤ 92%.
  • Normal saline 150 mL/hour IV.
  • Administer sequentially:
    1. Epinephrine (1 mg/mL) 0.5 mg IM — anterolateral mid-thigh preferred (deltoid if thigh not possible).
    2. Diphenhydramine 50 mg IV push over 2 minutes (if not given within last 30 minutes).
    3. Hydrocortisone 100 mg IV push over 1 minute.
  • Monitor vitals every 5 minutes and continuous SpO₂; activate emergency response.
Administer epinephrine IM regardless of platelet count when anaphylaxis is suspected.
Step 4 — Disposition & Documentation

Provider Evaluation & Paperwork

  • Responding Provider/emergency team evaluates for re-challenge, rate change, premed changes, or discontinuation.
  • Reassess need for IV fluids and supportive care.
  • Document: use HSR/Allergy orders, record as Observed ADR, include timing, symptoms, vitals, medications (dose/route/time), and response.

Quick Reference (Doses & Interventions)

Medication / SupportTypical Nurse Action
Diphenhydramine50 mg IV push over 2 minutes (see premed timing logic)
Cetirizine10 mg PO
Acetaminophen1,000 mg PO x 1 dose
Hydrocortisone100 mg IV push over 1 minute
Epinephrine (1 mg/mL)0.5 mg IM (anterolateral thigh preferred)
Oxygen2 L/min via NC if SpO₂ ≤ 92%
FluidsNormal saline 150 mL/hour IV
MonitoringVitals every 5 minutes; continuous SpO₂
⚠️ Not intended for pregnant patients. Follow obstetric-specific anaphylaxis pathways when applicable.

Flip Flashcards

Case Quiz

🧪12 questions
🧭Practice mode (instant feedback)
🎯Score: 0 / 0

How it works: Read each case, choose the best nursing action(s) per the Adult HSR/Allergic Reaction Management algorithm. Some questions are multi‑select.

Quick reference
  • First steps for any suspected HSR: Stop infusion, vitals q5 min, notify provider/activate response.
  • Hives/itching: Diphenhydramine 50 mg IV push over 2 min. If diphenhydramine was given within 30 min, still give 50 mg IV and add cetirizine 10 mg PO. Reassess in 5 min. If no improvement: hydrocortisone 100 mg IV push over 1 min; repeat diphenhydramine; ensure cetirizine given.
  • Fever/chills/rigors: Acetaminophen 1,000 mg PO x1 unless given within 4 h or patient is SCT—then get provider guidance before dosing.
  • Severe signs (hypotension, wheeze/SOB, angioedema): Epinephrine (1 mg/mL) 0.5 mg IM (anterolateral mid‑thigh) → Diphenhydramine 50 mg IV → Hydrocortisone 100 mg IV; O₂ 2 L/min NC if SpO₂ ≤92%; NS 150 mL/h; vitals q5; continuous SpO₂.
Reference: Adult Hypersensitivity (HSR)/Allergic Reaction Management – University of Texas MD Anderson Cancer Center, Department of Clinical Effectiveness V9, approved Aug 19, 2025. Not intended for pregnant patients.