You are in: eMedicine Specialties > Dermatology > ALLERGY AND IMMUNOLOGY Urticaria, PressureArticle Last Updated: Oct 2, 2006AUTHOR AND EDITOR INFORMATIONSection 1 of 10
  Author: Joslyn Sciacca-Kirby, MD, Staff Physician, Department of Dermatology, Hospital of the University of Pennsylvania Joslyn Sciacca-Kirby is a member of the following medical societies: American Academy of Dermatology, American Medical Association, and Philadelphia County Medical Society Coauthor(s): Ellen Kim, MD, Assistant Professor, Department of Dermatology, Hospital of the University of Pennsylvania School of Medicine; Robin M Levin, MD, Staff Physician, Assistant Professor, Department of Family Medicine, Division of Dermatology, Kennedy Hospital at Stratford; Warren R Heymann, MD, Head, Division of Dermatology, Professor, Department of Internal Medicine, University of Medicine and Dentistry of New Jersey Editors: Daniel J Hogan, MD, Director of Bay Pines Dermatology Residency Program, Bay Pines Veterans Affairs Healthcare System; Michael J Wells, MD, Associate Professor, Department of Dermatology, Texas Tech University Health Sciences Center; Jeffrey Meffert, MD, Assistant Clinical Professor of Dermatology, University of Texas Health Science Center-San Antonio; Catherine Quirk, MD, Clinical Assistant Professor, Department of Dermatology, Brown University; Dirk M Elston, MD, Director, Department of Dermatology, Geisinger Medical Center Author and Editor Disclosure Synonyms and related keywords: vibratory urticaria, delayed pressure urticaria, dermatographism, PU, physical urticaria INTRODUCTIONSection 2 of 10
  BackgroundPressure urticaria (PU) is an uncommon form of physical urticaria. It may occur immediately, within minutes, after a pressure stimulus. More commonly, wheals develop after a delay of 4-6 hours after a pressure stimulus. The lesions may last for 8-72 hours. The hands, the feet, the trunk, the buttocks, the legs, and the face are the most common areas affected. Lesions can be induced by a variety of stimuli, including standing, walking, wearing tight clothes, or sitting on a hard surface. PathophysiologyThe pathogenesis of PU is unknown. No allergen can usually be found. Mast cells are believed to play a role because injection of a compound "48/80", which causes depletion of mast cell mediators, prevents the induction of lesions in the injected area. Histamine levels are increased in lesional skin, and intracellular histamine levels are decreased in peripheral white blood cells. Despite these findings and the finding of increased stimulated histamine release, histamine is not likely to be the sole mediator in PU, given the relative unresponsiveness of conditions to antihistamine treatment. Other possible mediators include eosinophils, given the elevated numbers of eosinophils, eosinophil cationic protein (ECP), and interleukin 5 found on the biopsies of some patients with PU, particularly bullous PU. Interleukin 6 has also been found in elevated concentrations in lesional skin. FrequencyUnited StatesPU is considered a rare entity, but some investigators have suggested that PU may be more common but not consistently recognized. Mortality/MorbidityPU is a chronic disease, with a mean duration of 9 years (range, 1-40 y). Depending on the severity of the disease and the associated symptoms, PU can be disabling, especially in patients who perform manual labor. SexPU is slightly more common in men than in women. AgeThe peak age of onset is in the 20s and 30s (range, 5-63 y). CLINICALSection 3 of 10
History
Physical
Causes
DIFFERENTIALSSection 4 of 10
Angioedema, Acquired Angioedema, Hereditary Urticaria, Acute Urticaria, Chronic Urticaria, Dermographism Urticaria, Solar Urticarial Vasculitis
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| Drug Name | Prednisone (Deltasone, Sterapred) |
|---|---|
| Description | May decrease inflammation by reversing increased capillary permeability and suppressing PMN activity. Stabilizes lysosomal membranes and also suppresses lymphocyte and antibody production. |
| Adult Dose | 0.5-2 mg/kg/d or 5-60 mg PO qd; taper as condition improves; single morning dose is safer for long-term use, but divided doses have more anti-inflammatory effect |
| Pediatric Dose | Administer as in adults |
| Contraindications | Documented hypersensitivity; viral, fungal, tubercular skin, or connective-tissue infections; peptic ulcer disease; hepatic dysfunction; GI disease; cataract, glaucoma, and coadministration with live vaccines |
| Interactions | Coadministration with estrogens may decrease clearance; when used with digoxin, digitalis toxicity secondary to hypokalemia may increase; phenobarbital, phenytoin, and rifampin may increase metabolism of glucocorticoids (consider increasing maintenance dose); monitor for hypokalemia with coadministration of diuretics; efficacy of oral hypoglycemics (eg, metformin, sulfonylureas) my decrease |
| Pregnancy | B - Usually safe but benefits must outweigh the risks. |
| Precautions | Abrupt discontinuation of glucocorticoids may cause adrenal crisis; hyperglycemia, edema, osteonecrosis, myopathy, peptic ulcer disease, hypokalemia, osteoporosis, euphoria, psychosis, myasthenia gravis, growth suppression, and infections may occur with glucocorticoid use |
These agents may be useful in helping control symptoms of chronic urticaria, which frequently coexists with PU.
| Drug Name | Hydroxyzine (Atarax, Vistaril) |
|---|---|
| Description | Antagonizes H1 receptors in periphery. May suppress histamine activity in subcortical region of CNS. |
| Adult Dose | 0.5 mg/kg up to 25-50 mg PO q4-6h prn; not to exceed 600 mg/d |
| Pediatric Dose | 0.6 mg/kg/dose PO q6h 0.5-1 mg/kg per dose IM q4-6h |
| Contraindications | Documented hypersensitivity |
| Interactions | CNS depression may increase with alcohol or other CNS depressants, nonnarcotic analgesics, barbiturates, and alcohol |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Associated with clinical exacerbations of porphyria (may not be safe for patients with porphyria); ECG abnormalities (alterations in T waves) may occur; may cause drowsiness |
| Drug Name | Loratadine (Claritin) |
|---|---|
| Description | Selectively inhibits peripheral histamine H1 receptors. |
| Adult Dose | 10 mg/d PO on empty stomach Liver failure: 10 mg qod (on empty stomach) |
| Pediatric Dose | <2 years: Not established 2-6 years: 5 mg/d PO >6 years: Administer as in adults |
| Contraindications | Documented hypersensitivity |
| Interactions | Ketoconazole, erythromycin, procarbazine, and alcohol may increase levels |
| Pregnancy | B - Usually safe but benefits must outweigh the risks. |
| Precautions | Initiate therapy at lower dose in liver impairment |
| Drug Name | Desloratadine (Clarinex) |
|---|---|
| Description | Long-acting tricyclic histamine antagonist selective for H1 receptor. It is a major metabolite of loratadine, which after ingestion is extensively metabolized to active metabolite 3-hydroxydesloratadine. |
| Adult Dose | 5 mg PO qd |
| Pediatric Dose | <6 months: Not established 6-11 months: 1 mg PO qd 12 months to 5 years: 1.25 mg PO qd 6-11 years: 2.5 mg PO qd >12 years: Administer as in adults |
| Contraindications | Documented hypersensitivity to desloratadine or loratadine |
| Interactions | Limited data exist; erythromycin and ketoconazole increase desloratadine and 3-hydroxydesloratadine plasma concentrations, but no increase was observed in clinically relevant adverse effects, including QTc |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Decrease dose in hepatic impairment; rarely causes pharyngitis or dry mouth |
| Drug Name | Cetirizine (Zyrtec) |
|---|---|
| Description | Selectively inhibits histamine H1 receptor sites in blood vessels, GI tract, and respiratory tract, which, in turn, inhibits physiologic effects that histamine normally induces at H1 receptor sites. Once-daily dosing is convenient. Bedtime dosing may be useful if sedation is a problem. |
| Adult Dose | 5-10 mg PO qd |
| Pediatric Dose | Oral syr <6 months: Not established 6 months to 2 years: 2.5 mg PO qd; may increase dose for children 12 months to 2 years to 2.5 mg PO bid 2-5 years: 2.5 mg PO qd >5 years: 5-10 mg PO qd Chewable tab <2 years: Not established 2-5 years: For children taking cetirizine syrup 5 mg PO qd, may take chewable tab at same dose (do not substitute 5 mg chewable tab for children taking oral syrup 2.5 mg/d) >5 years and adults: 5-10 mg PO qd |
| Contraindications | Documented hypersensitivity |
| Interactions | CNS depression may increase with alcohol or other CNS depressants, nonnarcotic analgesics, barbiturates, and alcohol |
| Pregnancy | B - Usually safe but benefits must outweigh the risks. |
| Precautions | Caution in hepatic or renal dysfunction; doses higher than 10 mg/d may cause drowsiness |
NSAIDs are the most commonly used medications to control mild to moderate pain and to decrease inflammation. Sulfasalazine, steroids, and immunosuppressive agents are sometimes used. These agents have been used with variable success.
| Drug Name | Ibuprofen (Ibuprin, Advil, Motrin) |
|---|---|
| Description | NSAID with analgesic, anti-inflammatory, and antipyretic properties. Inhibits inflammatory reactions and pain by decreasing prostaglandin synthesis. |
| Adult Dose | 200 mg PO qid or 800 mg PO bid; higher doses have been tried with variable success; not to exceed 3.2 g/d |
| Pediatric Dose | 6 months to 12 years: 4-10 mg/kg/dose PO tid/qid; not to exceed 2.4 g/d >12 years: Administer as in adults |
| Contraindications | Documented hypersensitivity; peptic ulcer disease; recent GI bleeding or perforation; renal insufficiency; high risk of bleeding |
| Interactions | Coadministration with aspirin increases risk of inducing serious NSAID-related adverse effects; probenecid may increase concentrations and, possibly, toxicity of NSAIDs; may decrease effects of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; may increase PT when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently |
| Pregnancy | B - Usually safe but benefits must outweigh the risks. |
| Precautions | Category D in third trimester of pregnancy; caution in congestive heart failure, hypertension, and decreased renal and hepatic function; caution in coagulation abnormalities or during anticoagulant therapy |
| Drug Name | Naproxen (Aleve, Naprelan, Anaprox) |
|---|---|
| Description | Inhibits inflammatory reactions and pain by decreasing activity of cyclo-oxygenase, which results in a decrease of prostaglandin synthesis. |
| Adult Dose | 500 mg PO followed by 250 mg q6-8h; not to exceed 1.25 g/d |
| Pediatric Dose | <2 years: Not established >2 years: 2.5 mg/kg/dose PO; not to exceed 10 mg/kg/d |
| Contraindications | Documented hypersensitivity; peptic ulcer disease; recent GI bleeding or perforation; renal insufficiency |
| Interactions | Coadministration with aspirin increases risk of inducing serious NSAID-related adverse effects; probenecid may increase concentrations and, possibly, toxicity of NSAIDs; may decrease effects of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; may increase PT when taking anticoagulants (instruct patients to watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently |
| Pregnancy | B - Usually safe but benefits must outweigh the risks. |
| Precautions | Category D in third trimester of pregnancy; acute renal insufficiency, interstitial nephritis, hyperkalemia, hyponatremia, and renal papillary necrosis may occur; patients with preexisting renal disease or compromised renal perfusion risk acute renal failure; leukopenia rarely occurs, is transient, and usually returns to normal during therapy; persistent leukopenia, granulocytopenia, or thrombocytopenia warrants further evaluation and may require discontinuation of drug |
Some recent small studies have shown efficacy in reducing the size, erythema, and pruritus associated with PU lesions.
| Drug Name | Clobetasol Propionate (Clobex, Olux, Embeline, Temovate) |
|---|---|
| Description | Class I superpotent topical steroid; suppresses mitosis and increases synthesis of proteins that decrease inflammation and cause vasoconstriction. Decreases inflammation by stabilizing lysosomal membranes, inhibiting PMN leukocytes and mast cell degranulation. |
| Adult Dose | Topically apply bid for up to 2 wk; not to exceed 50 g/wk |
| Pediatric Dose | Not established |
| Contraindications | Documented hypersensitivity; viral or fungal skin infections |
| Interactions | None reported |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | May suppress adrenal function in prolonged therapy |
Article Last Updated: Oct 2, 2006
