What Are Early Bullous Pemphigoid Relapse Symptoms?

If you have been in remission (a period where your disease is quiet and controlled) from bullous pemphigoid, it is natural to wonder how a relapse (a return of disease activity) might look. While some relapses start directly with new blisters, many people first notice intense, unexplained itching (pruritus) or a hive-like rash before any blisters form ^[1][2]. Recognizing these possible early signs can help you seek medical assessment sooner, which may allow your care team to adjust your treatment before a full flare-up occurs ^[3].

The Early (Prodromal) Phase

In the weeks or months before blisters appear, your skin may show other changes ^[1]. This non-blistering stage is known as the prodromal phase. Common early signs can include:

• Intense Itching (Pruritus): A return of severe, persistent itching is often the earliest clue ^[4].
• Urticarial Plaques: These are raised, red, hive-like patches. While typical allergic hives usually fade within 24 hours in a single spot, these plaques persist and do not go away quickly ^[5].
• Eczema-like Rashes: You may develop dry, red, or scaly patches that resemble eczema ^[6].

Because these symptoms can also be caused by dry skin, new medications, or common allergies, an itch or rash does not automatically mean your bullous pemphigoid has returned. However, it does warrant a check-in with your doctor.

Progression to Blistering

If early signs are part of a relapse, they may eventually progress to a full blistering flare-up, though this is not inevitable for everyone:

• Tense Blisters: The classic symptom of bullous pemphigoid is the appearance of firm, fluid-filled blisters (bullae). These often form on top of the red, hive-like patches or on normal-appearing skin ^[7][8].
• Common Locations: Blisters most frequently appear on the arms, legs, and trunk ^[9].
• Erosions: As blisters break, they leave behind raw, painful sores called erosions ^[7], which can be vulnerable to infection.

How common is a relapse? Relapse estimates vary widely—from roughly 28% to 74%—depending on the specific clinical study, the treatments used, and how long patients were followed ^[10][11]. Research suggests that many relapses occur within the first six months after reaching remission, but they can still happen later on ^[10].

Mucous Membrane Symptoms and Urgent Care

In a minority of cases, bullous pemphigoid can affect the mucous membranes—the moist linings of your mouth, throat, eyes, and genitals ^[12]. While mucosal involvement does not automatically mean your overall disease is more severe, it requires prompt medical attention ^[13].

Seek urgent or emergency medical care if you experience:

• Vision changes or eye pain: Severe redness, pain, light sensitivity, or a gritty feeling in your eyes require urgent ophthalmic assessment, as scarring can threaten your vision ^[14].
• Throat or airway issues: Difficulty breathing, throat swelling, hoarseness, or an inability to swallow liquids warrant immediate emergency care ^[15][16].
• Signs of severe infection: Rapidly spreading blisters, fever, extreme dehydration, or increased warmth, swelling, and pus around open erosions require prompt escalation.

What to Do if You Suspect a Relapse

If you notice new or worsening symptoms compared to your baseline, contact your dermatologist promptly.

• Do not change your medications: Never restart, stop, or adjust your prescribed steroids or immunosuppressive drugs without your doctor’s supervision.
• Be cautious with over-the-counter (OTC) treatments: If you need interim itch relief, ask your pharmacist or doctor before taking OTC antihistamines. Because many patients with bullous pemphigoid are older adults, sedating antihistamines (like diphenhydramine) can increase the risk of falls, confusion, and urinary issues.
• Prepare for your appointment: Take dated photographs of new rashes or blisters in good light, and bring a current list of all your medications.

How your doctor will check for a relapse:
A skin examination is the first step. Your doctor may run blood tests (such as the BP180 and BP230 antibody tests) as supportive tools; however, these blood tests cannot definitively prove or rule out a relapse on their own, as antibodies can remain detectable even when the disease is quiet ^[17][18]. Ultimately, diagnosis depends on your clinical symptoms, and your doctor will decide if a repeat skin biopsy (taking small samples of affected and unaffected skin for specialized testing) is needed ^[17].