|Classification and external resources|
CU on the volar aspect of the forearm
CU was first described by Duke in 1924. The term cholinergic derives from the finding that hives similar to those of CU can be elicited using cholinergic agonists (e.g. methacholine), thus suggesting the etiology of CU to includes events that are triggered by a cholinergic stimulus.
CU presents with a number of small, short-lasting hives that develops usually in response to exercise, bathing, staying in a heated environment, or emotional stress. Although the symptoms subside rapidly, commonly within 1 hour, CU may significantly impair quality of life, especially in relation to sporting and sexual activities.
Sweat hypersensitivity 
This subtype refers to those with CU who are hypersensitive to their own sweat.
Wheals are observed coinciding with perspiration points of sweating.
Tanaka et al. found that the sweat-induced release of histamine from basophils is mediated by specific IgE for the partially purified antigen present in the sweat of patients with atopic dermatitis. The sweat hyper-sensitivities of CU and atopic dermatitis seem to be virtually the same, and therefore, the sweat-induced histamine release from basophils may also be mediated by a specific IgE for sweat in atopic dermatitis as well as CU.
- Proposed first-line treatment: Rapid desensitization protocol using autologous sweat.
- Non-pharmacological treatment: Forced perspiration by excessive body warming (hot bath or exercise) used daily may reduce the symptoms of prickling pain through exhaustion of inflammatory mediators. Contraindicated in those with CU as a result of hypohidrosis (see below).
- Antihistamines are a commonly prescribed first-line treatment for conventional urticaria, but its effectiveness in the treatment of CU is rather limited in most cases.
- Treatment(s) with mixed success: omalizumab (anti-igE therapy), danazol (synthetic androgen), propranolol (beta blocker).
Acquired anhidrosis and/or hypohidrosis 
This subtype refers to those with CU who have abnormally reduced sweating.
Sweat is readily visualized by a topical indicator such as iodinated starch or sodium alizarin sulphonate. Both undergo a dramatic colour change when moistened by sweat. A thermoregulatory sweat test evaluates the body’s response to a thermal stimulus by inducing sweating through the use of a hot box ⁄ room, thermal blanket or exercise. Failure of the topical indicator to undergo a colour change during thermoregulatory sweat testing can indicate anhidrosis and/or hypohidrosis (see minor test).
A skin biopsy may reveal cellular infiltrates in sweat glands or ducts.
Severe heat intolerance (e.g., nausea, dizziness, and headache), and tingling, pricking, or burning pain over the entire body on exposure to hot environments or prolonged exercise which improve after cooling the body. Occurs in the absence of any causative skin, metabolic, or neurological disorders. Uniquely the adrenergic innervated apocrine sweat glands remain functional.
- Non-pharmacological treatment: In the absence of sweat, cold-water sprays and wet towels can be used increase the evaporative loss of heat from the skin. Shifting to a cooler or air-conditioned environments when necessary can also reduce discomfort. In the event of severe hyperthermia (body temperature >106 °F), drastic measures such as immersion in ice-cold water are necessary to prevent irreversible brain damage.
Unknown or unclassified at this time. Representing those who do not fall under any of the above categories.
See also 
- Nakamizo, S.; Egawa, G.; Miyachi, Y.; Kabashima, K. (2012). "Cholinergic urticaria: Pathogenesis-based categorization and its treatment options". Journal of the European Academy of Dermatology and Venereology 26 (1): 114–116. doi:10.1111/j.1468-3083.2011.04017.x. PMID 21371134.
- DUKE WW. URTICARIA CAUSED SPECIFICALLY BY THE ACTION OF PHYSICAL AGENTS: (LIGHT, COLD, HEAT, FREEZING, BURNS, MECHANICAL IRRITATION, AND PHYSICAL AND MENTAL EXERTION). JAMA. 1924;83(1):3-9. doi:10.1001/jama.1924.02660010007002.
- Moore-Robinson, M.; Warin, R. P. (1968). "Some clinical aspects of cholinergic urticaria". The British journal of dermatology 80 (12): 794–799. doi:10.1111/j.1365-2133.1968.tb11948.x. PMID 5706797.
- Hirschmann, J. V.; Lawlor, F.; English, J. S.; Louback, J. B.; Winkelmann, R. K.; Greaves, M. W. (1987). "Cholinergic urticaria. A clinical and histologic study". Archives of dermatology 123 (4): 462–467. PMID 3827277.
- Poon, E.; Seed, P. T.; Greaves, M. W.; Kobza-Black, A. (1999). "The extent and nature of disability in different urticarial conditions". The British journal of dermatology 140 (4): 667–671. doi:10.1046/j.1365-2133.1999.02767.x. PMID 10233318.
- Kozaru, T.; Fukunaga, A.; Taguchi, K.; Ogura, K.; Nagano, T.; Oka, M.; Horikawa, T.; Nishigori, C. (2011). "Rapid Desensitization with Autologous Sweat in Cholinergic Urticaria". Allergology International 60 (3): 277–281. doi:10.2332/allergolint.10-OA-0269. PMID 21364312.
- Bito, T.; Sawada, Y.; Tokura, Y. (2012). "Pathogenesis of cholinergic urticaria in relation to sweating". Allergology international : official journal of the Japanese Society of Allergology 61 (4): 539–544. doi:10.2332/allergolint.12-RAI-0485. PMID 23093795.
- Kobayashi, H.; Aiba, S.; Yamagishi, T.; Tanita, M.; Hara, M.; Saito, H.; Tagami, H. (2002). "Cholinergic urticaria, a new pathogenic concept: Hypohidrosis due to interference with the delivery of sweat to the skin surface". Dermatology (Basel, Switzerland) 204 (3): 173–178. PMID 12037443.
- Metz, M.; Bergmann, P.; Zuberbier, T.; Maurer, M. (2008). "Successful treatment of cholinergic urticaria with anti-immunoglobulin E therapy". Allergy 63 (2): 247–249. doi:10.1111/j.1398-9995.2007.01591.x. PMID 18186820.
- Sabroe, R. A. (2010). "Failure of omalizumab in cholinergic urticaria". Clinical and Experimental Dermatology 35 (4): e127–e129. doi:10.1111/j.1365-2230.2009.03748.x. PMID 19925484.
- La Shell, M. S.; England, R. W. (2006). "Severe refractory cholinergic urticaria treated with danazol". Journal of drugs in dermatology : JDD 5 (7): 664–667. PMID 16865874.
- Pachor, M. L.; Lunardi, C.; Nicolis, F.; Cortina, P.; Accordini, C.; Marchi, G.; Corrocher, R.; De Sandre, G. (1987). "Usefulness of propranolol in the treatment of cholinergic urticaria". La Clinica terapeutica 120 (3): 205–210. PMID 2973859.
- Ammann, P.; Surber, E.; Bertel, O. (1999). "Beta blocker therapy in cholinergic urticaria". The American journal of medicine 107 (2): 191. PMID 10460061.
- Chia, K. Y.; Tey, H. L. (2012). "Approach to hypohidrosis". Journal of the European Academy of Dermatology and Venereology: no. doi:10.1111/jdv.12014. PMID 23094789.
- Nakazato, Y.; Tamura, N.; Ohkuma, A.; Yoshimaru, K.; Shimazu, K. (2004). "Idiopathic pure sudomotor failure: Anhidrosis due to deficits in cholinergic transmission". Neurology 63 (8): 1476–1480. PMID 15505168.
- Ohshima, Y.; Yanagishita, T.; Ito, K.; Tamada, Y.; Nishimura, N.; Inukai, Y.; Iwase, S.; Sugenoya, J. et al. (2012). "Treatment of patients with acquired idiopathic generalized anhidrosis". British Journal of Dermatology: no. doi:10.1111/j.1365-2133.2012.11112.x. PMID 22709381.
- Thami, G. P.; Kaur, S.; Kanwar, A. J. (2003). "Acquired idiopathic generalized anhidrosis: A rare cause of heat intolerance". Clinical and experimental dermatology 28 (3): 262–264. PMID 12780708.