National Center for Advancing and Translational Sciences Genetic and Rare Diseases Information Center, a program of the National Center for Advancing and Translational Sciences

Aquagenic urticaria

Aquagenic urticaria is a rare condition in which urticaria (hives) develop rapidly after the skin comes in contact with water, regardless of its temperature. It most commonly affects women and symptoms often start around the onset of puberty. Some patients report itching too. It is a form of physical urticaria. The exact underlying cause of aquagenic urticaria is currently unknown.  Due to the rarity of the condition, there is very limited data regarding the effectiveness of individual treatments; however, various medications and therapies have been used with variable success.[1][2]
Last updated: 6/20/2016
Aquagenic urticaria is a rare condition in which itchy urticaria (hives) develop rapidly after the skin comes in contact with water, regardless of its temperature. The hives associated with aquagenic urticaria are typically small (approximately 1-3 mm), red- or skin-colored welts (called wheals) with clearly defined edges. The rash most commonly develops on the neck, upper trunk and arms, although it can occur anywhere on the body. Some people have itching too. Once the water source is removed, the rash generally fades within 30 to 60 minutes.[1][2]
Last updated: 6/20/2016
The exact underlying cause of aquagenic urticaria is poorly understood. However, scientists have proposed the following theories:[1][2]
  • A substance dissolved in water enters the skin and triggers an immune response. In this theory, the hives are not caused by water, specifically, but rather an allergen in the water.
  • An interaction between water and a substance found in or on the skin generates a toxic material, which leads to the development of hives.
Last updated: 6/20/2016
Most cases of aquagenic urticaria seem to occur sporadically in people with no family history of aquagenic urticaria. However, familial cases have been reported on several occasions, with one report describing the disease in three generations of a single family.[1][3] Some familial cases have been reported in association with other conditions, some of which can be familial. In other words, the family members who had aquagenic urticaria also had another potentially inherited medical condition.[3] However, to our knowledge, no specific inheritance pattern has been definitively associated with aquagenic urticaria.
Last updated: 6/20/2016
A diagnosis of aquagenic urticaria is typically suspected based on the presence of characteristic signs and symptoms. A "water challenge test" may then be ordered to confirm the diagnosis. During this test, a compress of 35ºC water is applied to the upper body for 30 minutes.[1][2] The upper body is chosen as the preferred site for the test because other areas, such as the legs, are affected less commonly.  It is important to tell the patient to not have any antihistamines for several days before the test.[1]

In some case reports, rinsing specific areas of the body with water or giving a direct bath and shower challenges has been attempted. Use of these tests may be needed when the usual water challenge test using a small water compress is negative, although it should be avoided in patients who have a history of serious symptoms.[1]
Last updated: 6/20/2016
Due to the rarity of aquagenic urticaria (AU), there is very limited data regarding the effectiveness of individual treatments. To date, no large-scale studies have been conducted. Unlike other types of physical urticaria where one can avoid the agent that causes the hives, avoidance of water is not practical.[4][5] The following treatments (alone or in various combinations) have been used to manage or treat AU with variable results:[4][5][6][7][8][9]
  • Antihistamines – These typically are used as the first-line medical therapy for all forms of urticaria. Those that block H1 receptors (H1 antihistamines) and are non-sedating, such as cetirizine, are preferred. Other H1 antihistamines (such as hydroxyzine) or H2 antihistamines (such as cimetidine) may be tried if H1 antihistamines are not effective.
  • Creams or other topical agents that serve as a barrier between water and the skin, such as petrolatum-based products. These may be used prior to bathing or other exposure to water to prevent water penetration into the skin.
  • Ultraviolet light therapy (also called phototherapy), such as Psoralens ultraviolet radiation A (PUVA) and ultraviolet radiation B, have been reported to resolve symptoms of AU in a few cases.
  • Omalizumab – an injectable medication typically used for people with severe asthma. This medication has reportedly been tried successfully in a few people with AU.
Due to the lack of strong evidence of the safety and effectiveness of the treatments mentioned above for people with AU specifically, those with AU should consult with their doctors regarding personal treatment options. Some people with AU may not experience improvement of symptoms with medical treatment and may need to rely on minimizing water exposure by limiting bathing time and avoiding water-based activities.[6]
Last updated: 1/24/2019

Research helps us better understand diseases and can lead to advances in diagnosis and treatment. This section provides resources to help you learn about medical research and ways to get involved.

Clinical Research Resources

  • ClinicalTrials.gov lists trials that are related to Aquagenic urticaria. Click on the link to go to ClinicalTrials.gov to read descriptions of these studies.

    Please note: Studies listed on the ClinicalTrials.gov website are listed for informational purposes only; being listed does not reflect an endorsement by GARD or the NIH. We strongly recommend that you talk with a trusted healthcare provider before choosing to participate in any clinical study.

Support and advocacy groups can help you connect with other patients and families, and they can provide valuable services. Many develop patient-centered information and are the driving force behind research for better treatments and possible cures. They can direct you to research, resources, and services. Many organizations also have experts who serve as medical advisors or provide lists of doctors/clinics. Visit the group’s website or contact them to learn about the services they offer. Inclusion on this list is not an endorsement by GARD.

Social Networking Websites

Living with a genetic or rare disease can impact the daily lives of patients and families. These resources can help families navigate various aspects of living with a rare disease.

Financial Resources

  • The HealthWell Foundation provides financial assistance for underinsured patients living with chronic and life-altering conditions. They offer help with drug copayments, deductibles, and health insurance premiums for patients with specific diseases. The disease fund status can change over time, so you may need to check back if funds are not currently available.

These resources provide more information about this condition or associated symptoms. The in-depth resources contain medical and scientific language that may be hard to understand. You may want to review these resources with a medical professional.

Where to Start

  • DermNet NZ is an online resource about skin diseases developed by the New Zealand Dermatological Society Incorporated. DermNet NZ provides information about this condition.
  • MedlinePlus was designed by the National Library of Medicine to help you research your health questions, and it provides more information about this topic.
  • The National Organization for Rare Disorders (NORD) has a report for patients and families about this condition. NORD is a patient advocacy organization for individuals with rare diseases and the organizations that serve them.

In-Depth Information

  • Medscape Reference provides information on this topic. You may need to register to view the medical textbook, but registration is free.
  • The Monarch Initiative brings together data about this condition from humans and other species to help physicians and biomedical researchers. Monarch’s tools are designed to make it easier to compare the signs and symptoms (phenotypes) of different diseases and discover common features. This initiative is a collaboration between several academic institutions across the world and is funded by the National Institutes of Health. Visit the website to explore the biology of this condition.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Aquagenic urticaria. Click on the link to view a sample search on this topic.

Questions sent to GARD may be posted here if the information could be helpful to others. We remove all identifying information when posting a question to protect your privacy. If you do not want your question posted, please let us know.

  1. Dice JP, Gonzalez-Reyes E. Physical urticarias. UpToDate. Waltham, MA: UpToDate; March, 2016; https://www.uptodate.com/contents/physical-urticarias.
  2. Park H, Kim HS, Yoo DS, Kim JW, Kim CW, Kim SS, Hwang JI, Lee JY, Choi YJ. Aquagenic urticaria: a report of two cases. Ann Dermatol. December 2011; 23(Suppl 3):S371-4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3276800/.
  3. Kai A, Flohr C. Aquagenic urticaria in twins. World Allergy Organ J. January 31, 2013; 6(1):2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3646536/.
  4. Wong HK. Urticaria (Hives). Medscape Reference. June 13, 2018; https://emedicine.medscape.com/article/762917-overview.
  5. Hamie L, Abou-Rahal J. Water-related dermatoses. Int J Dermatol. December 2, 2018; [Epub ahead of print]:https://www.ncbi.nlm.nih.gov/pubmed/30506676.
  6. Rothbaum R, McGee JS. Aquagenic urticaria: diagnostic and management challenges. Journal of Asthma and Allergy. November 29, 2016; 2016(9):209-213. https://www.dovepress.com/aquagenic-urticaria-diagnostic-and-management-challenges-peer-reviewed-fulltext-article-JAA.
  7. Damiani G, Diani M, Conic RRZ. Omalizumab in Chronic Urticaria: An Italian Survey. Int Arch Allergy Immunol. 2019; 178:45–49. https://www.ncbi.nlm.nih.gov/pubmed/30396176.
  8. Rorie A, Gierer S. A case of aquagenic urticaria successfully treated with omalizumab. J Allergy Clin Immunol Pract. May-June, 2016; 4(3):547-548. https://www.jaci-inpractice.org/article/S2213-2198(16)00008-8/abstract.
  9. Rivard J, Lim HW. Ultraviolet phototherapy for pruritus. Dermatologic Therapy. July, 2005; 18(4):344-354. https://www.ncbi.nlm.nih.gov/pubmed/16297008.