Can a viral infection cause a rash?

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Last updated: April 14, 2025 • View editorial policy

From the Guidelines

Yes, you can develop a rash after a viral infection, as evidenced by various viral infections such as measles, chickenpox, and roseola, which can cause rashes as part of their clinical presentation 1, 2.

Common Viral Infections Causing Rashes

  • Measles: characterized by a maculopapular rash
  • Chickenpox: typically presents with a vesicular rash
  • Roseola: often causes a maculopapular rash
  • Fifth disease: known for its distinctive "slapped-cheek" appearance
  • Influenza and COVID-19: can cause post-viral rashes, although less common

Post-Viral Rash Characteristics

  • Typically appears as the viral infection is resolving or shortly afterward
  • Presents as flat, red or pink spots that may be slightly raised
  • Can appear anywhere on the body
  • Usually resolves on its own within a few days to weeks without specific treatment

Symptom Relief

  • Over-the-counter antihistamines like diphenhydramine (Benadryl) 25-50mg every 4-6 hours or cetirizine (Zyrtec) 10mg daily
  • Topical calamine lotion or 1% hydrocortisone cream applied to affected areas 2-3 times daily
  • Cool baths with colloidal oatmeal can help soothe itching

When to Seek Medical Attention

  • If the rash is severe, painful, blistering, accompanied by high fever, or doesn't improve within a week
  • As it could indicate a more serious condition or secondary infection, such as encephalitis or sepsis, which require prompt medical attention 1, 2

From the Research

Viral Infections and Rashes

  • Viral infections can cause rashes, which can present in different ways, including reactive patterns in the skin to infection elsewhere in the body or infection within the affected skin itself 3.
  • Recognizing the possible systemic symptoms, characteristic distribution, and morphology of rashes can lead to a high degree of accuracy in making a clinical diagnosis 3.

Types of Viral Infections that Can Cause Rashes

  • Herpes zoster, also known as shingles, can cause a rash and is often treated with antiviral medications such as valaciclovir or acyclovir 4, 5.
  • Herpes simplex can also cause a rash and is treated with antiviral medications such as valaciclovir or acyclovir 5.
  • Varicella-zoster virus (VZV) infection can cause a rash and is prevented by vaccines and treated with antiviral agents such as acyclovir or valaciclovir 6.

Differential Diagnosis of Viral Rashes

  • Differential diagnosis of viral rashes can be challenging, especially in cases where the rash appears during antibiotic therapy and concomitant viral infection 7.
  • The absence of eosinophilia, low RegiSCAR score, confirmation of viral etiology, and rapid resolution of the rash may help to rule out drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome 7.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Comparative study of the efficacy and safety of valaciclovir versus acyclovir in the treatment of herpes zoster.

Journal of microbiology, immunology, and infection = Wei mian yu gan ran za zhi, 2001

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.