Hives, Urticaria, and Angioedema: Symptoms and Causes

This post was written with Consensus AI Academic Search Engine – please read our Disclaimer at the end of this article. Hives and angioedema are common manifestations of urticaria, with symptoms ranging from transient hives to deeper swelling in angioedema. The causes are diverse, involving both immunological and non-immunological mechanisms, with triggers including autoantibodies, NSAIDs, and certain food additives. Understanding these causes is crucial for managing and preventing episodes of urticaria and angioedema.

Symptoms

Hives, also known as urticaria, are characterized by the sudden appearance of weals or hives on the skin, which can peak within minutes to hours and typically resolve within 24 hours. These hives are often accompanied by intense itching, which tends to worsen at night1. Angioedema, which can occur with or without hives, involves deeper swelling of the skin and mucous membranes, often affecting areas such as the face, lips, and throat2. In chronic spontaneous urticaria (CSU), patients frequently experience severe itching and numerous hives, with some also experiencing angioedema2.

Causes

The underlying cause of urticaria involves the degranulation of cutaneous mast cells, which can be triggered by various factors. These include immunological causes, such as the presence of functional autoantibodies against the high-affinity receptor for IgE (FcεRI) or against IgE itself, which are found in up to half of patients with chronic idiopathic urticaria (CIU)1. Non-immunological triggers, such as hypersensitivity reactions to nonsteroidal anti-inflammatory drugs (NSAIDs), can also induce urticaria and angioedema. These reactions are often nonallergic and may be prevented by avoiding the triggering drug or using antihistamines and leukotriene antagonists3.

Additionally, certain food additives and medications, such as acetylsalicylic acid, can exacerbate symptoms in individuals with chronic urticaria, suggesting that mediators other than histamine, like leukotrienes, may play a role in the pathogenesis of the condition6. Interestingly, despite anecdotal reports, studies have shown that aspartame is no more likely than a placebo to cause urticaria or angioedema, indicating that not all suspected dietary triggers are valid4.

Disclaimer

The content presented in this blog is generated by Consensus, an AI-powered academic search engine, and is based on publicly available scientific literature. While every effort is made to provide accurate, up-to-date, and well-researched information, the content is intended for informational and educational purposes only. It does not constitute medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional before making any decisions regarding medical conditions, treatments, or medications. The AI system’s analysis may not cover all perspectives, emerging research, or individual cases, and it is not a substitute for professional expertise. Neither the blog publisher nor the developers of the AI-powered search engine are responsible for any actions taken based on the information provided in this content. Use of this information is at your own risk. Citations to the original scientific studies are included for reference, but these studies should be reviewed in full and interpreted with the guidance of a healthcare or research professional.

If you are experiencing a medical emergency, please seek immediate attention from a healthcare provider.