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Immunotherapy FAQs

Immunotherapy

How Long Do IVIG Side Effects Last?

  • Most IVIG side effects are mild and short-lived, typically resolving within 24 to 48 hours after an infusion. 
  • Common reactions such as headache, fatigue, fever, chills, and nausea generally improve within one to two days, though some patients may experience lingering symptoms for up to 72 hours. 

How Long Do Different IVIG Side Effects Last?

Side EffectTypical DurationWhen to Call Your Doctor
HeadacheA few hours to 72 hoursPersists >72 hrs or is severe
Fatigue24–48 hoursExtreme tiredness lasting >3 days
Fever / ChillsA few hours to 1 dayFever above 38.5°C / 101.3°F
NauseaUp to 24 hoursVomiting or inability to eat/drink
Muscle aches1–2 daysSevere or spreading pain
Site reactionsHours after infusionSwelling spreading beyond the site

How to Reduce the Duration of IVIG Side Effects

Infusion nurses and pharmacists use several strategies to minimize IVIG side effects:

  • Pre-medications — acetaminophen, diphenhydramine (Benadryl), or corticosteroids may be given before the infusion to reduce reactions
  • Slower infusion rates — reducing the drip speed can lower the risk of headache and systemic reactions
  • Staying hydrated — drinking plenty of fluids before and on infusion day is associated with fewer headaches
  • Rest after infusion — scheduling low-demand activities for the day of and day after treatment helps manage fatigue

Read more about IVIG and side effects here: 

Is Immunotherapy Right For You?

If your doctor has recommended immunotherapy or you'd like to learn whether immunotherapy may be an option for you, contact AmeriPharma Specialty Care to speak with a specialist today.

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