Urticaria, commonly known as hives, is a skin rash characterized by itchy, raised bumps that can appear anywhere on the body. It is often caused by allergic reactions. Chronic hives persist for over six weeks, while acute hives resolve within six weeks. Treatment involves identifying and avoiding triggers as well as using antihistamines to reduce symptoms. More severe cases may require stronger medications like corticosteroids. Contact dermatitis is skin irritation or rash caused by contact with an allergen or irritant and can be classified as allergic, irritant, or photocontact dermatitis.

2. URTICARIA
 Commonly referred to as hives, is a kind
of skin rash notable for pale red, raised,
itchy bumps. Hives are frequently caused
by allergic reactions

3. Urticaria - Causes
The majority of chronic hives cases have
an unknown (idiopathic).
Acute viral infection is another common
cause of acute urticaria (viral exanthem)
Less common causes of hives include
friction, pressure, temperature extremes,
exercise, and sunlight.

4. APPEARANCE OF
SYMPTOMS
Wheals (raised areas surrounded
by a red base) from urticaria can
appear anywhere on the surface of
the skin.
Wheals may be pinpoint in size, or
several inches in diameter.
Fluid leakage from superficial
blood vessels

5. Immunologic Mechanism:
(A) Type I -HYPERSENSITIVITY REACTION.
(B) Type III- HYPERSENSITIVITY REACTION.
Non Immunologic Mechanism
(a) direct effect
(b) effect on archidonic acid metabolism-
Leukotrien B4
(C) idiopathic or undetermined

6. CLASSIFICATION
1.Acute Urticaria.
Presence of evanescent wheals which completely
resolve within six weeks.
2.Chronic urticaria (ordinary urticaria)
Presence of evanescent wheals which persist
for greater than six weeks.

7. Food item: Spicy food, Egg, Fish, Strawberry even milk
and it product.
Drug: Aspirin, Certain Antibiotics, NSAID. ,Codeine ,
Morphine.
Inhalants :- Pollen - Spore – House Dust Mite.
INFECTION AND INFESTATION:
 Psychological factor play important role
Certain systemic diseases : Malignancy [lymphoma ]
endocrine.
Diseases as [thyrotoxicosis . polycythemia] , Liver
Disease, Pregnancy

8. Drug-induced urticaria
Urticaria by infection or
environmental agent
Dermatographic urticaria
Pressure or delayed pressure
Classification By Cause

9. Classification …
 Chronic cold urticaria
 Solar urticaria
 Water-induced urticaria
 Exercise urticaria

10.  General : CBP , ESR, GSE, GUE, urine and blood
sugar, liver and renal function tests.
 Skin test: commonly used in patient with chronic
urticaria.
 Certain disease commonly associated with chronic
urticaria as sinus infection, UTI, hyperthyroidism,
intestinal warms, internal malignancy, lymphoma,
pregnancy and chronic exposure to external allergen.

11. It can be difficult to determine appropriate
medications, since some, such as loratadine, require a
day or two to build up to effective levels, and the
condition is intermittent and outbreaks typically clear up
without any treatment.
Treatment plans for urticaria involve being aware of
one's triggers
Antihistamines such as diphenhydramine may be
used.
MANAGEMENT

12.  85/15 ratio of skin H1/H2 receptors
 Combination of anti H1&2 provides
additional treatment benefit
 Doxepin blocks both receptors and
is a more potent anti-H1 blocker than
diphenhydramine or hydroxizine
 Sedation may limit usefulness of
doxepin

13.  Zafirlukast and montelukast superior to placebo
in treatment of chronic urticaria.
 Have not been compared to therapy with
antihistamines.
 No additional effect once maximal antihistamine
effect achieved.

14.  Oral sympathomimetics (e.g., terbutaline) studied to reduce
erythema / swelling
 Side effects substantial (insomnia, tachycardia)
 Efficacy low
SYMPATHOMIMETIC
AGENTS

15.  Indicated when inadequate response to
histamine receptor blockers and leukotriene
receptor antagonists
 Effective but with substantial side effects
 Alternate day therapy if must be used
 One approach – start 15-20 mg qod and taper
to 2.5-5mg q three weeks, d/c after 4-5 months

16. Experimental
Therapies
 Cyclosporine at low doses (2.5-3 mg/kg) effective and
steroid sparing
 High dose (6 mg/kg) very effective but with severe side
effects
 Other agents less well studied include sulfasalazine,
hydroxychloroquine and dapsone, IV IgG
 Plasmapheresis for patients with anti-IgE Ab effective but
impractical for long-term treatment

17. Recommendations
 Laboratory workup rarely necessary (except thyroid
evaluation)
Antihistamines mainstay of therapy (H1and H2)
Nonsedating at low/high doses effective for mild/moderate
disease
Older, sedating antihistamines more effective for severe
urticaria and/or angioedema
Minimize systemic corticosteroids (alternate day)

18. Contact Dermatitis
It is a term for a skin reaction (dermatitis) resulting
from exposure to allergens (allergic contact dermatitis)
or irritants (irritant contact dermatitis).
Phototoxic dermatitis occurs when the allergen or
irritant is activated by sunlight.

19. Symptoms
 Localized rash or irritation of the skin caused by contact
with a foreign substance.
Only the superficial regions of the skin are affected in
contact dermatitis.
Contact dermatitis results in large, burning, and itchy rashes,
and these can take anywhere from several days to weeks to
heal.

20. Causes
The most common causes of allergic contact
dermatitis a
The alkyl resorcinols in Grevillea banksii and
Grevillea 'Robyn Gordon' are responsible for
contact dermatitis re plants of the
Toxicodendron genus.
Other common causes of irritant contact
dermatitis are harsh (highly alkaline) soaps,
detergents, and cleaning products.

21. Classification
Irritant contact dermatitis
Allergic contact dermatitis
Photocontact dermatitis

22. Self-care at home.
Immediately after exposure to a known allergen or irritant,
wash with soap and cool water to remove or inactivate
most of the offending substance.
Medical care
Corticosteroids.
Antihistamines.