Flu shot and psoriasis spots

Could Your Flu Shot Trigger Psoriasis? What You Need to Know

Soraya Malik in Health & Wellness December 2025 • 3 min read.

"Uncover the surprising link between the H1N1 vaccine and new-onset guttate psoriasis, empowering you with knowledge and proactive health strategies."

Since the H1N1 influenza vaccine's introduction in 2009, various adverse events, both serious and non-serious, have been documented. These reactions typically include pain, redness, tenderness, and hardening at the injection site, which usually subside within a few days following the vaccination.

However, a recent study has brought to light a less common but noteworthy reaction: the onset of guttate psoriasis. This skin condition is characterized by small, scaly, red or pink, teardrop-shaped spots on the skin. While the connection is rare, understanding the potential link between the H1N1 vaccine and psoriasis can empower individuals to make informed decisions about their health.

This article delves into the details of a specific case study where a 26-year-old woman developed guttate psoriasis following the H1N1 vaccine. We will explore the symptoms, diagnosis, treatment, and potential reasons behind this unexpected reaction.

The Case: New Onset Guttate Psoriasis Following Pandemic H1N1 Influenza Vaccination

In a documented case, a 26-year-old woman developed multiple erythematous, scaly macules on her extremities and trunk after receiving an inactivated split-virus influenza A/H1N1 vaccine without adjuvant (Greenflu-SⓇ).

The initial lesion appeared at the injection site three days post-vaccination, with subsequent lesions spreading to the trunk and extremities. Histopathological examinations revealed specific characteristics indicative of psoriasis, including neutrophilic collections, moderate acanthosis, and dilated capillaries.

Symptoms: Multiple small, scaly, red or pink spots on the skin, mainly on the trunk and extremities.
Diagnosis: Physical examination and skin biopsy to confirm the presence of psoriatic features.
Treatment: Topical steroids and ultraviolet B (UVB) phototherapy to manage the skin lesions.
Outcome: Successful treatment within three weeks with no relapse during the 14-month follow-up period.

Researchers suggest that the onset of guttate psoriasis in this case might be linked to the H1N1 vaccine acting as a trigger in a predisposed individual.

Takeaway: Weighing the Benefits and Risks

While this case highlights a potential association between the H1N1 vaccine and guttate psoriasis, it's essential to maintain perspective. The incidence of such reactions remains rare, and the benefits of influenza vaccination in preventing severe illness and complications far outweigh the risks for most individuals. If you have concerns about psoriasis or other potential vaccine reactions, consult with your healthcare provider to make informed decisions based on your individual health profile.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.5021/ad.2013.25.4.489, Alternate LINK

Title: New Onset Guttate Psoriasis Following Pandemic H1N1 Influenza Vaccination

Subject: Dermatology

Journal: Annals of Dermatology

Publisher: Korean Dermatological Association and The Korean Society for Investigative Dermatology

Authors: Moon Seub Shin, Soo Jin Kim, Seong Hyun Kim, Yee Gyoung Kwak, Hai-Jin Park

Published: 2013-01-01

Everything You Need To Know

What exactly is guttate psoriasis and why is it important to know about in relation to vaccinations?

Guttate psoriasis is a skin condition characterized by small, scaly, red or pink, teardrop-shaped spots on the skin. It's significant because, in rare cases, it has been linked to the H1N1 influenza vaccine. Understanding this potential connection allows individuals to be more informed about their health and any post-vaccination skin changes. While this form of psoriasis is often linked to a trigger, other forms of psoriasis exist such as plaque psoriasis that are more chronic.

What are the typical symptoms someone might experience if they develop guttate psoriasis?

The primary symptoms of guttate psoriasis include the appearance of multiple small, scaly, red or pink spots on the skin, predominantly on the trunk and extremities. These spots are often teardrop-shaped. If you notice such symptoms, it's important to consult a healthcare provider for a proper diagnosis, which may involve a physical examination and potentially a skin biopsy to confirm the presence of psoriatic features and rule out other conditions.

How is guttate psoriasis diagnosed by a doctor?

The diagnosis of guttate psoriasis typically involves a physical examination by a healthcare provider to assess the characteristic skin lesions. A skin biopsy may be performed to confirm the presence of psoriatic features under microscopic examination. These features include neutrophilic collections, moderate acanthosis, and dilated capillaries. Accurate diagnosis is important to differentiate guttate psoriasis from other skin conditions with similar symptoms.

What are the common treatments available for guttate psoriasis?

Treatment options for guttate psoriasis often include topical steroids to reduce inflammation and scaling, and ultraviolet B (UVB) phototherapy, which can help clear the skin lesions. In some cases, a combination of treatments may be used for optimal results. Treatment duration and approach can vary depending on the severity and extent of the condition. Other psoriasis treatments exist like systemic medications and biologics that are typically reserved for more severe or resistant cases of psoriasis.

Is there a real connection between the H1N1 vaccine and developing guttate psoriasis, and what does that mean for me?

The H1N1 vaccine has been associated, in rare instances, with the onset of guttate psoriasis, potentially acting as a trigger in predisposed individuals. This means that the vaccine may initiate the skin condition in someone who already has a genetic or immunological susceptibility. However, it's crucial to remember that the benefits of the H1N1 vaccine in preventing severe influenza and its complications generally outweigh this risk. Consulting with a healthcare provider can help you make an informed decision based on your individual health profile and risk factors.