Urticaria is an allergic skin rash also known as 'nettle rash' or hives. There are two distinct type
Urticaria is an allergic skin rash also known as 'nettle rash' or hives. There are two distinct types: acute urticaria is often caused by an allergy and can last between several hours and six week chronic urticaria persists beyond six weeks. Most hives go away within days to a few weeks. Occasional unlucky individuals will have itches and swellings that come and go over many years. Urticaria is cla ified as either acute or chronic. Acute urticaria is defined as urticaria that has been present for le than 6 weeks. Chronic urticaria is defined as urticaria that has been continuously or intermittently present for at least 6 weeks. The 6-week period is a guide and not an a olute demarcation.Skin lesio and pruritus occur, caused by an allergic or nonallergic mechanism.
Urticaria occurs following release of histamine, bradykinin, kallikrein, and other vasoactive su tances from mast cells and basophils, resulting in intradermal edema from capillary and venous vasodilation and occasionally from leukocyte infiltration. Urticaria has four major mechanisms. Most commonly, it is a manifestation of acute immunoglobulin E (IgE)mediated hyperse itivity with histamine and other vasoactive peptides released from mast calls and basophils. Nonimmunologic urticaria occurs when an exogenous su tance results in mast cell degranulation either by direct stimulation of the mast cell or by unknown mechanisms (reaction to intravenous contrast dye). A irin and other no teroidal anti-inflammatory drugs ( AIDs) cause urticaria by a nonmast cell mechanism, e ecially in asthmatics.
Causes of Urticaria
1.Allerge .
2.Environmental factors.
3.Drugs.(Penicillin).
4.Urticaria and alcohol.
5.Emotional factors( emotionalstre es).
Symptoms of Urticaria
1.Rash
2.Itchine
3.Stre .
4.Swelling
Treatment of Urticaria
Oral antihistamines control wealing and itching for the majority of patients with urticaria. Avoid a irin and codeine. It is usually safe to take paracetamol and the newer Cox-II inhibitor anti-inflammatories and avoid alcohol. Non-sedating antihistamines (loratidine, fexofenadine, terfenadine, cetirazine, and astemizole) are le likely to cause drowsine than the le expe ive conventional antihistamines. They may be u uitable in pregnancy. Terfenadine and astemizole may increase the risk of a ormal heart rhythms. They should be avoided if you have heart disease or you are also taking erythromycin, ketoconazole and some other medicatio . Fexofenadine, loratidine, desloratidine and cetirazine are safe. Oral steroids (prednisone) are useful for severe acute urticaria but u uitable long term because of serious adverse effects. Antifungal agents, used to clear an a umed underlying infection.
Urticaria occurs following release of histamine, bradykinin, kallikrein, and other vasoactive su tances from mast cells and basophils, resulting in intradermal edema from capillary and venous vasodilation and occasionally from leukocyte infiltration. Urticaria has four major mechanisms. Most commonly, it is a manifestation of acute immunoglobulin E (IgE)mediated hyperse itivity with histamine and other vasoactive peptides released from mast calls and basophils. Nonimmunologic urticaria occurs when an exogenous su tance results in mast cell degranulation either by direct stimulation of the mast cell or by unknown mechanisms (reaction to intravenous contrast dye). A irin and other no teroidal anti-inflammatory drugs ( AIDs) cause urticaria by a nonmast cell mechanism, e ecially in asthmatics.
Causes of Urticaria
1.Allerge .
2.Environmental factors.
3.Drugs.(Penicillin).
4.Urticaria and alcohol.
5.Emotional factors( emotionalstre es).
Symptoms of Urticaria
1.Rash
2.Itchine
3.Stre .
4.Swelling
Treatment of Urticaria
Oral antihistamines control wealing and itching for the majority of patients with urticaria. Avoid a irin and codeine. It is usually safe to take paracetamol and the newer Cox-II inhibitor anti-inflammatories and avoid alcohol. Non-sedating antihistamines (loratidine, fexofenadine, terfenadine, cetirazine, and astemizole) are le likely to cause drowsine than the le expe ive conventional antihistamines. They may be u uitable in pregnancy. Terfenadine and astemizole may increase the risk of a ormal heart rhythms. They should be avoided if you have heart disease or you are also taking erythromycin, ketoconazole and some other medicatio . Fexofenadine, loratidine, desloratidine and cetirazine are safe. Oral steroids (prednisone) are useful for severe acute urticaria but u uitable long term because of serious adverse effects. Antifungal agents, used to clear an a umed underlying infection.
