Mechanism of Action
Download
Report
Transcript Mechanism of Action
Antihistamines & Corticosteroids
for Disorders of Skin
2007.9.21
R2 윤인기
ANTIHISTAMINES
Diphenhydramine
Description
A popular antihistamine due to its relative safety
after oral or parenteral administration
An H1-antagonist of the ethanolamine class
Ethanolamine H1-antagonists
Significant antimuscarinic activity and produce marked
sedation in most patients
Other members of this group
carbinoxamine, clemastine, dimenhydrinate (a salt of
diphenhydramine), doxylamine, phenyltoloxamine and
others
Diphenhydramine
Drug Effects
For the usual allergic symptoms, irritant cough, airway drying
effect
Relief of nausea, vomiting, and vertigo associated with
motion sickness
Treatment of drug-induced extrapyramidal symptoms as well
as to treat mild cases of Parkinson's disease.
As an OTC hypnotic
Minimal gastrointestinal side effects
Approval by FDA
Originally approved by the FDA in 1946 as a prescriptiononly drug but was later changed to non-prescription status
Diphenhydramine
Mechanism of Action-1
Not prevent the release of histamine
(as do cromolyn and nedocromil)
Competes with free histamine for binding at
H1-receptor sites
Competitively antagonizes the effects of histamine
on H1-receptors
In the GI tract, uterus, large blood vessels, and bronchial
muscle.
Suppresses the formation of edema, flare, and
pruritus that result from histaminic activity
Diphenhydramine
Mechanism of Action-2
Greater anticholinergic activity than do other
antihistamines as ethanolamine derivatives
Antidyskinetic action of diphenhydramine
A direct suppressive action on the cough center and causes
sedation via CNS depression
Topical diphenhydramine
Providing local relief from insect bites, minor burns, sunburn,
or minor abrasions
Due to an anesthetic effect resulting from decreased
permeability of nerve cell membranes to sodium ions
(preventing the transmission of nerve impulses)
Occurrence of tolerance
Following prolonged use
Beneficial because of reduced sedative effects
Diphenhydramine
Pharmacokinetics-1
Administered orally, topically, intravenously, or
intramuscularly
Less soluble H1-antagonists
Slower onset of action & less likely to cause toxicity
Onset of action following oral administration
15-30 minutes
The time of peak concentrations
2-4 hours
The duration of action ranges
4-6 hours
The duration of the maximum sedative effect
1-3 hours
Diphenhydramine
Pharmacokinetics-2
The onset of antiextrapyramidal effects following an
intramuscular injection
15-30 minutes
Highly protein-bound
Widely distributed in body tissues and fluids
Crosses the placenta and is excreted into breast milk.
Metabolism
In the liver to produce diphenylmethoxyacetic acid, which
then becomes conjugated
Plasma half-life
2-8 hours
Most unchanged drug and metabolites
Excreted renally within 24—48 hours of a dose.
Hydroxyzine
Hydroxyzine-HCl Tablet (Tab 25 mg)
Description
A piperazine antihistamine (H1-blocker) structurally related to
buclizine, cyclizine, and meclizine
Drug effects
Effective in treating histamine-mediated pruritus or pruritus
due to atopy or other allergic conditions
Used as a perioperative sedative and anxiolytic
Effective alternative treatment for anxiety disorders
Used to alleviate nausea and control emesis perioperatively
The intramuscular (IM) dosage form
Used for the symptomatic management of acute alcohol withdrawal
Hydroxyzine
Known as one of the most sedating H1-blockers
a small study showed that hydroxyzine produced less sedation than
either azatadine or clemastine
Approval by FDA
Originally approved by the FDA in 1956.
Officially discontinued all product lines of the Atarax® brand
name on May 4, 2004 by Pfizer
Hydroxyzine
Mechanism of Action
Competes with histamine for H1-receptor sites on the
effector cell surface
Blockade of H1-receptors
Suppression of the formation of edema, flare, and pruritus
that result from histaminic activity
The dose-related sedative properties
At the subcortical level of the CNS
Antiemetic actions secondary to its central
anticholinergic actions
Antiarrhythmic, analgesic, local anesthetic, and
skeletal muscle relaxant properties
Bronchodilatory and mild antisecretory effects
Not used as potent analgesics
Hydroxyzine
Pharmacokinetics-1
Administered orally or intramuscularly
Rapidly absorbed following oral administration
The onset of effect for hydroxyzine
15-60 minutes
Thel duration of action
4-6 hours
The inflammatory response and pruritus
Suppressed for up to 4 days
Distribution of hydroxyzine
Not fully described
Unknown whether it crosses the placenta or is distributed
into breast milk
Hydroxyzine
Pharmacokinetics-2
Metabolized in the liver
Cetirizine
One of active metabolite; mostly excreted renally as
unchanged drug
The elimination half-life of hydroxyzine
14—25 hours
Cetirizine
Zyrtec Tablet (Tablet 5 mg)
Description
The active metabolite of hydroxyzine, a piperazine
H1-receptor antagonist
Different from the parent compound by having greater
affinity for the H1-receptor
Drug effects
Effective in the treatment of chronic idiopathic urticaria,
perennial allergic rhinitis, and seasonal allergic rhinitis
For the treatment of allergic asthma, physical urticaria
(triggered by physical stimuli)
For symptomatic relief of atopic dermatitis
Cetirizine
Drug Effects
A higher incidence of somnolence than the non-sedating
antihistamines fexofenadine and loratadine
The cardiovascular safety in drug-interaction studies
elevated-dose studies, and clinical trials
Good tolerance in pediatric and elderly patients
Approval by FDA
Initially FDA-approved on December 8, 1995
An expansion of labeling for use in infants as young as 6
months of age
For the treatment of allergic rhinitis and chronic urticaria
FDA-approved in October 2002
A chewable tablet
FDA-approved in March 2004
Cetirizine
Mechanism of Action
High affinity for histamine H1-receptors
Less affinity than terfenadine or hydroxyzine for calciumchannel, alpha-adrenergic, D2-dopamine, 5HT2-serotonin,
muscarinic receptors
A low incidence of sedation compared with older antihistamines
The less lipophilic carboxyl group to the ethylamine side chain
reduces the penetration of cetirizine into the CNS
Dose-related drowsiness
The action of cetirizine in the inflammatory response involving
a number of mediators
Affecting cell adhesion
Decrease of leukotriene C4 production
Suppression of neutrophil migration in IgE-mediated reactions
Reduction of eosinophil infiltration to nasal mucosa in patients
with seasonal allergic rhinitis
Cetirizine
Pharmacokinetics
Administered orally
Rapid onset (time to Cmax)
1 hour
Long duration of action
The overall bioavailability
Not altered by the presence of food, although the rate of
absorption can be slightly reduced
Poor penetration into the CNS
Metabolized to limited extent via O-dealkylation
The elimination half-life of cetirizine
6.5 -10 hours (mean 8.3 hours)
Astemizole
Description
An oral H1-receptor antagonist similar in structure to
terfenadine, another H1-receptor antagonist
Structurally related to haloperidol, a butyrophenone
antipsychotic
Drug effects
Unlike other H1-antagonists, therapeutic doses of
astemizole produce insignificant anticholinergic activity or
sedation
Extremely long duration of action
Relieves symptoms associated with chronic idiopathic
urticaria and seasonal allergic rhinitis
Not be used PRN for the immediate relief of symptoms
Due to the poor penetration into the CNS
Due to its slow onset of action
Associated with QT prolongation and torsades de pointes
Astemizole
Approval by the FDA
In December 1988 and came off patent in 1997
Discontinuation from manufacture in the US by
Janssen Pharmaceutica in June 1999
Due to low prescription usage and the availability of other
agents with less propensity for adverse effects and drug
interactions
Fexofenadine
Allegra Tablet (Tab 180 mg)
Description
An H1-receptor antagonist
The active metabolite of another H1-antagonist,
terfenadine
Drug effects
Both fexofenadine and terfenadine are non-sedating
Unlike terfenadine, fexofenadine does not cause QT
prolongation when given in doses up to 800 mg/day
or when administered concomitantly with
ketoconazole or erythromycin
Fexofenadine
Approval by FDA
First approved by the FDA in July 1996
for seasonal allergic rhinitis, subsequent approval was
granted in February 2000 for children as young as 6
years old
For the treatment of chronic idiopathic urticaria in
adults and children in February 2000.
Oral liquid formulation & Orally disintegrating tablet
Approved in October 2006 and in July 2007, respectively
For seasonal allergic rhinitis and chronic idiopathic
urticaria in children
Fexofenadine
Mechanism of Action
Not prevent the release of histamine as do cromolyn
and nedocromil
Competes with free histamine for binding at the H1receptor.
relatively irreversible H1-receptor antagonism at
higher concentrations
Lipophilic compared to first generation
antihistamines
Not readily cross the blood-brain barrier.
Minimal CNS depression compared with other H1antagonists.
Fexofenadine
Pharmacokinetics
Administered orally and is rapidly absorbed.
the mean time to maximum plasma concentrations
following oral administration with tablets or oral
solution
2-3 hours and 1 hour, respectively.
The mean time to maximum plasma concentrations of
the Orally Disintegrating Tablet (ODT) formulation
2 hours post-dose
The absolute bioavailability of fexofenadine: unknown
The mean elimination half-life
14.4 hours in normal volunteers receiving 60 mg twice daily.
Loratadine
Loratadine Tablet (Tablet 10 mg)
Description
An oral non-sedating H1-blocker similar in structure
to cyproheptadine and azatadine, other H1-blockers.
Differs structurally from the other non-sedating H1blockers terfenadine and astemizole
Administered once daily
Drug effects
The CNS effects are less with loratadine compared to the
traditional H1-blockers (due to poor penetration into the CNS
and a low affinity for CNS H1-receptors)
Not associated QT prolongation or torsades de pointes.
(Unlike astemizole and terfenadine, loratadine)
Loratadine
Approval by FDA
First approved in April 1993
An OTC loratadine oral solution
To relieve the symptoms associated with seasonal
allergic rhinitis
Approved in June 2006
An OTC 12-hour oral disintegrating tablet
(Claritin® RediTabs® 12 Hour)
Approved on December 12, 2006
For the temporary relief of hay fever or other upper
respiratory allergies to include symptoms such as
rhinorrhea, sneezing, itchy, watery eyes, and itching
of the nose or throat
Loratadine
Mechanism of Action
Competes with free histamine for binding at the H1-receptor.
Pharmacokinetics
Administered orally
The onset of action of loratadine
1-3 hours
Peak effects in 8-12 hours
Duration of action greater than 24 hours
The normal mean elimination half-lives of loratadine and its
metabolite
8.4 hours (range 3-20 hours) and 28 hours, respectively.
Elimination occurs through the fecal and renal routes
Ranitidine
Ranitidine Tablet (Tab 300 mg)
Description
An antagonist at histamine H2-receptors.
The actions and indications for ranitidine differ
little from other H2-blockers
5-12 times more potent as a histamine receptor
antagonist (compared to cimetidine)
Less affinity for the cytochrome P450 hepatic
enzyme system
Much less likely than cimetidine to interact with
other drugs
Ranitidine
Drug effects
For the treatment of various gastrointestinal disorders
Approval by FDA
First approved as Zantac® in June 1983
A non-prescription (OTC) formulation (75 mg tablets)
approved in December 1995
Ranitidine
Mechanism of Action-1
Competitively inhibition of the binding of histamine to
receptors on gastric parietal cells (designated as the
H2-receptor)
Reduction of basal and nocturnal gastric acid
secretion
Decrease of the amount of gastric acid released
In response to stimuli such as food, caffeine, insulin,
betazole, or pentagastrin
Reduction of the total volume of gastric juice
Indirectly decreasing pepsin secretion
Ranitidine
Mechanism of Action-2
Aid of gastromucosal healing & protection of the
mucosa
From the irritant effects caused by aspirin and nonsteroidal
antiinflammatory agents
Combination therapy with an H1-receptor antagonist
Stimulation of both H1- and H2-receptors expressed by
Human skin mast cells
Blocking both the initial and delayed histaminic response
Suppressing the formation of edema, flare, and pruritus that
results from histaminic activity
Ranitidine
Pharmacokinetics
Administered either orally or parenterally
Intramuscular (IM) administration
A bioavailability of 90-100% versus intravenous (IV) administration.
The oral bioavailability of ranitidine
About 50-60%
The duration of effects
8-12 hours.
Partial metabolism (30%) in the liver
Both the unchanged drug and its metabolites
Excreted in the urine and feces
The half-life of the drug
2-3 hours but increases to roughly 5 hours in patients with renal
impairment (CrCl < 35 ml/min).
3-4 hours in elderly patients with decreased renal function
Cimetidine
Cimetidine Tablet (Tab 400 mg)
Description
The first commercially available drug to be used for
peptic ulcer disease
An oral H2-receptor antagonist similar to
famotidine, nizatidine, and ranitidine
A known inhibitor of many of the isoenzymes of the
hepatic CYP450 enzyme system
Exhibition of many significant drug interactions with other
medications
Used mainly for treating gastrointestinal disorders
Approval by FDA
First approved in 1977
Cimetidine
Mechanism of Action
Blocking the effects of histamine at the receptor located on the
basolateral membrane of the parietal cell (designated as the H2receptor)
Decreasing the amount of gastric acid
Not reducing acid-output as dramatically as the proton-pump
inhibiting medications (e.g., omeprazole)
Exhibition of weak anti-androgenic effects
Combination therapy with an H1-receptor antagonist
Suppression of the formation of edema, flare, and pruritus that
results from histaminic activity by blocking both the initial and
delayed histaminic response
Cimetidine
Pharmacokinetics
Rrapidly and completely absorbed in the GI tract
Oral bioavailability: 60-70%
Distribution throughout body tissues
Found in breast milk, and crosses the placenta.
Extensively metabolized predominately to a sulfoxide metabolite
following oral administration
Half-life
2 hours in patients with normal renal function.
Management of Acute Urticaria and
Angioedema
Antihistamines (both H1 and H2)
The first-line drugs
H1 antihistamines
Diphenhydramine:12.5 to 100 mg per dose every 4 hrs
Nonsedating agents
Cetirizine, Loratadine, or Fexofenadine
For stabilizing any respiratory insufficiency &
hemodynamic instability in the emergency
department
Hydroxyzine (10 to 100 mg daily at bedtime)
Can be tried when other H1 antihistamines are
inadequate
Decrease of histamine-induced urticarial reaction
by adding an H2 blocker (e.g., ranitidine or
cimetidine)
Histamine receptors in the skin: H1 (85%) & H2 (15%)
Doxepin (25 to 100 mg/day)
An excellent alternative as it has both H1 and H2 activity
Treatment for Hereditary Angioedema
Life-threatening acute attacks
Not usually respond satisfactorily to treatment with
epinephrine in normal dosage, antihistamines, or
steroids
Active airway management
The mainstay of treatment
Fresh frozen plasma (C1 inhibitor)
Effective in abolishing acute attacks
High-dose epinephrine with caution
Second-Line Therapy for Anaphylaxis
All patients with anaphylaxis should receive
histamine-1 (H1) blockers
Diphenhydramine
The most commonly used H1 antihistamine
The typical dose
A loading dose
50 mg every 4 to 6 hours in adults or 5 mg/kg/day in divided
doses for the pediatric population
1 to 2 mg/kg intravenously (IV) to a maximum of 100 mg
for severe reactions
Too large a dose or too rapid administration
Marked sedation and hypotension
Cf) Diphenhydramine: intravenous (or oral) (Rosen’s)
Adult
50 mg, up to 400 mg/24 hr, titrated to effects
Pediatric
1 mg/kg, up to 300 mg/24 hr, titrated to effects
Chlorpheniramine
The alkylamine family (chlorpheniramine maleate)
Administration to children by the same routes
At a standard dose of 10 to 20 mg or 0.35 mg/kg/day in
divided doses
Histamine-2 (H2) blockers
Effective in shock refractory to epinephrine, fluids, steroids,
and H1 blockers
Common in refractory urticaria; however, clear evidence of
benefit from controlled trials is lacking
Ranitidine and cimetidine
Ranitidine: intravenous (or oral)
Adult: 50 mg
Pediatric: 1 mg/kg
Cimetidine
Should not be used for patients who are elderly (side
effects), with multiple comorbidities (interference with
metabolism of many drugs) have renal or hepatic impairment
Or whose anaphylaxis is complicated by beta-blocker use
(prolongs metabolism of -blockers and may prolong
anaphylactic state)
After the initial intravenous dose of steroids and
antihistamines, the patient may be switched to oral
medication (Table 34-2)
Management of Dermatologic
Disease
Antihistamines (H1 antagonists)
Used frequently in the management of dermatologic disease,
particularly in the control of pruritus
The first-generation antihistamines
Diphenhydramine and hydroxyzine
Used PO, IM, or IV
The second-generation antihistamine agents (newer
agents)
Astemizole, cetirizine, fexofenadine, and loratadine
Offer the advantages of reduced dosing frequency and less
sedative effect
More costly
The use of topical antihistamine preparations
Discouraging because these agents are readily absorbed
Dosing is therefore difficult to predict
Suggested dosing, administration schedules, and
routes of therapy
H2 antagonists (ranitidine or famotidine)
Some benefit in the patient with an allergic-mediated event,
in particular urticaria
Other recommended antipruritic therapies
Domeboro solution (aluminum sulfate diluted 1:10 with water)
soaks, potassium permanganate baths, and oatmeal baths
CORTICOSTEROIDS
CORTICOSTEROIDS
The production of the adrenal gland (cortex)
More than 50 different steroids, grouped into three classes
according to their effects
Glucocorticoids
Mineralocorticoids
Androgenic steroids
Major effects of Corticosteroids
Anti-inflammatory
Antipruritic
Vasoconstrictive properties
Glucocorticoids
Cortisol
The most abundant steroid produced by the adrenals
representative of this class
Involved in the regulation of a number of metabolic
pathways
Including gluconeogenesis, fat redistribution, protein
metabolism, and calcium balance
Some mineralocorticoid effects
Active in the synthesis of medullary catecholamines
as well as beta-adrenergic receptors
Important role in the maintenance of vascular tone and
cardiac contractility
Glucocorticoids
Other hemodynamic effects
Maintaining endothelial integrity
Controlling vascular permeability
Total daily production of cortisol
Approximately 25 mg in the nonstressed state
Free forms
Only 5 to 10 percent is free and physiologically active
Bound forms
The remainder is bound to plasma proteins, principally (80
percent) cortisol-binding globulin
Mineralocorticoids
Aldosterone
The principal mineralocorticoid produced by the adrenals.
Alteration of electrolyte and fluid balance by facilitating
sodium resorption and hydrogen and potassium excretion
Regulation of Aldosterone
ACTH has a minor influence on its secretion
the primary regulators: the renin-angiotensin system and
serum potassium levels
Mineralocorticoids
Stimulation by the diminished glomerular filtration
seen in volume depletion
→ Release of prorenin from the juxtaglomerular apparatus
→ Release of aldosterone from the adrenals
→ Resorption of sodium and water in the distal tubules at
the expense of potassium loss
Minor degrees of hyperkalemia
Directly stimulate the adrenals to secrete aldosterone
The net result
Increase of serum volume while depleting potassium
Edema and hypertension
Adrenal Androgens
Under the control of ACTH
The same diurnal rhythm as cortisol
A minor contributor to total androgen levels in the
male
Significant source in the female
Leading to some of the signs of adrenal insufficiency in
these patients
Mechanism of Action
Lipocortins
Peptides induced by corticosteroids at the cellular level
Phospholipase A2
the breakdown of leukocyte lysosomal membranes to release
arachidonic acid
Antagonized by lipocortins
decrease of the subsequent formation and release of
endogenous inflammatory mediators including prostaglandins,
kinins, histamine, liposomal enzymes and the complement
system
Mechanism of Action
Early anti-inflammatory effects of topical
corticosteroids
Inhibition of macrophage and leukocyte movement and
activity in the inflamed area by reversing vascular dilation
and permeability
Later inflammatory processes
Capillary production, collagen deposition, keloid (scar)
formation
Inhibition by corticosteroids
Decrease of edema, erythema, pruritus, plaque formation and
scaling of the affected skin
Hydrocortisone
Ala Cort Cream (Cream1% ) Cortef Tablet (Tab 10 mg)
Description
A steroid hormone secreted by the adrenal cortex
Both mineralocorticoid actions and glucocorticoid
actions
Commercially available forms
The unchanged hormone
Hydrocortisone acetate, hydrocortisone cypionate
Hydrocortisone sodium phosphate, hydrocortisone butyrate
Hydrocortisone valerate, and hydrocortisone sodium succinate
Hydrocortisone
Hydrocortisone
The preferred glucocorticoid for replacement therapy in
patients with adrenal insufficiency
Although some patients require concomitant administration
of a more potent mineralocorticoid, such as fludrocortisone,
to treat this condition
Topical hydrocortisone
Low potency topical corticosteroids
the safest for chronic use and may be used on the face or
intertriginous areas, with occlusion, and in infants and young
children
Approved by the FDA in 1951
Hydrocortisone
Pharmacokinetics
Rapidly absorbed following an oral dose
The time of peak effects following oral and IV
administration
Within 1-2 hours
The onset and duration of action
Depend on type of injection (e.g., intra-articular or IM
injection) and the extent of the local blood supply
Distribution of Methylprednisolone
Quickly distributed into the kidneys, intestines, skin, liver,
and muscle
Distribute into breast milk and cross the placenta
Hydrocortisone
Pharmacokinetics
Metabolism
Topical preparations of hydrocortisone
Metabolized in the skin
Systemic hydrocortisone
Metabolized by the liver to inactive metabolites
Excretion in the urine
The biologic half-life of hydrocortisone
8-12 hours
Methylprednisolone
A-Methapred Powder for Injection (Injection 125 mg)
Description
A synthetic glucocorticoids used orally or parenterally
as antiinflammatory or immunosuppressive agents
Very little mineralocorticoid activity
not used to manage adrenal insufficiency unless a more
potent mineralocorticoid is administered concomitantly.
Originally approved by the FDA in 1957
Methylprednisolone
Pharmacokinetics
Route of administeration
Orally
Methylprednisolone sodium succinate: by IM or IV injection
or by IV infusion.
Methylprednisolone acetate: by IM, intra-articular,
intralesional, or soft tissue injection.
The time of peak effects following oral and IV
administration
1-2 hours
Methylprednisolone
Pharmacokinetics
The duration of absorption of methylprednisolone
from an intra-articular injection site
Over about 7 days
Distribution of Methylprednisolone
Metabolism
The biologic half-life of methylprednisolone
18—36 hours
Prednisone
Prednisone Tablet (Tab 1 mg)
Description
the most commonly-prescribed oral corticosteroid.
Potency relative to hydrocortisone
Roughly 4 times as potent as a glucocorticoid
Diuration of action
Intermediate between hydrocortisone and dexamethasone
Common Uses
Allograft rejection, asthma, systemic lupus erythematosus,
and many other inflammatory states
Very little mineralocorticoid activity
First approved by the FDA in 1955
Prednisone
Pharmacokinetics
Rapidly absorbed across the GI membrane following
oral administration
The time of peak effects
1—2 hours
The plasma elimination half-life
1 hour
The biological half-life of prednisone
18—36 hours
Many Medical indications for Glucocorticoid
therapy
1. Rheumatoid arthritis
2. Psoriatic arthritis
3. Gouty arthritis
4. Bursitis and tenosynovitis
5. Systemic lupus erythematosus
6. Acute rheumatic carditis
7. Pemphigus
8. Erythema multiforme
9. Exfoliative dermatitis
10. Mycosis fungoides
11. Allergic rhinitis
12. Bronchial asthma
13. Atopic dermatitis
14. Serum sickness
15. Allergic conjunctivitis
16. Uveitis
17. Retrobulbarneuritis
18. Sarcoidosis
19. Löffler's syndrome
20. Berylliosis
21. Idiopathic thrombocytopenic
purpura
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
Autoimmune hemolytic anemia
Lymphomas
Immune nephritis
Tuberculous meningitis
Urticaria
Chronic active hepatitis
Ulcerative hepatitis
Regional enteritis
Nontropical sprue
Dental postoperative
inflammation
Cerebral edema
Subacute nonsuppurative
thyroiditis
Malignant exophthalmos
Hypercalcemia
Trichinosis
Myasthenia gravis
Organ transplantation
Alopecia areata
Management of Acute Urticaria and
Angioedema
Topical steroids
No value
Systemic steroids
should be reserved for pressure urticaria, vasculitis
urticaria, and intractable chronic urticaria
Second-Line Therapy for Anaphylaxis
All patients with anaphylaxis should receive
corticosteroids
Treatment of anaphylaxis refractory to the first-line
treatments or associated with complications
Prevention of recurrences
Others
Antihistamines, asthma medications, and glucagon, etc.
Systemic corticosteroids
Late onset of action
Approximately 4 to 6 hours after administration
Limited benefit in the acute treatment of the anaphylactic
patient
Clinical Uses
Most useful in persistent bronchospasm or hypotension
Should be used to prevent the biphasic reaction of
anaphylaxis
Rare cases of deterioration after corticosteroid
administration
The result of anaphylactic sensitivity to this medication
Systemic corticosteroids
Hydrocortisone (Solu-Cortef)
Adult: 250 to 500 mg (or 1g; Rosen’s) IV
Children: 5 to 10 mg/kg; up to 500 mg
Methylprednisolone (Solu-Medrol)
Adult: 125 to 250 mg IV
Children: 2 mg/kg; up to 125 mg (40-80 mg IV; Rosen’s)
Produces less fluid retention than does hydrocortisone
Preferred for elderly patients and for those patients in whom
fluid retention would be problematic (e.g., renal and cardiac
impairment)
Acceptable regimen after the anaphylactic episode
Corticosteroid IV followed by oral prednisone over 7 to 10
days
Management of Skin Disorders
Potential indications for systemic corticosteroids
Urticaria, angioedema, and toxicodendron dermatitis (rhus,
poison ivy, or poison oak) and other contact or allergic
dermatitides
Treatment benefits
Dermatologic syndromes (erythema multiforme, toxic
epidermal necrolysis, and vasculitis)
Reduction of pruritis & urticaria
Small bursts of prednisone (40 mg daily for 4 days) in one
study
Poison ivy or oak
best treated with systemic steroids only after consultation with
a dermatologist.
Systemic steroids; oral prednisone (1 mg/kg body weight) with
a slow 2- to 3-week taper.
Other contact or allergic dermatitides
Benefit from an abbreviated course (4 days) of oral prednisone
Management of Skin Disorders
Relative Contraindication or cautions of oral
corticosteroids
In those with diabetes, hypertension, active peptic ulcer
disease, psychiatric disease, and immunodeficiency.
Close follow-up is needed if oral corticosteroids are
prescribed to these patients.
Topical corticosteroids
Powerful and useful tools in the management of
dermatologic disease.
Numerous agents
Different in concentration, base components, and cost
Familiarity with a single agent in each potency class
Sufficient to safely and effectively treat any steroidresponsive skin ailment
Topical corticosteroids
Measurement of corticosteroid potency or strength
(i.e., the anti-inflammatory property)
Rated by vasoconstricting ability on a scale of one to seven,
with lower scale numbers correlating with more potent
corticosteroids
Group 1 agents: the most powerful corticosteroids
Group 7 agents: the least potent
Table 245-7 for a listing of topical corticosteroid agents relative
to group potencies
Use of the appropriate-strength topical steroid
Strongly encouraged at the start of therapy
The use of a less powerful agent
Not likely to spare the patient from potential adverse effect
or produce adequate control of the disease
Topical corticosteroids
Hydrocortisone
The most frequently used topical corticosteroid in the
outpatient setting
Used safely on most body surfaces, including the face,
genitalia, flexure creases, and intertriginous zones
Safe for use in infants and children
A poor choice for the treatment of diseases involving the
palms and soles
Relatively low-potency in penetration of skin
Triamcinolone acetonide & fluocinoline acetonide
Corticosteroids of moderate potency
Useful in severely inflamed skin and on the thicker skin
(the scalp, trunk, extensor surfaces, palms, and soles)
Should not be applied to the face or genitals or used in the
infant
Topical corticosteroids
Fluorination in many corticosteroids
Greatly increases the potency
Increases the risk of adverse reactions
Should not be used in pregnancy
Recommendations of corticosteroid potency
relative to dermatologic disease
Topical corticosteroids
Different skin surfaces
Different response rate varies relative to the absorption of
the steroid into the deeper tissues
The relatively thin skin surfaces of the face
Respond very rapidly to the use of group 7 agents
The thicker skin of the palms and soles
Requires a highly potent steroid
Topical corticosteroids
Irritations that resolve with an effective, higher
potency application when using a low-potency agent
Raw & inflamed skin
More rapidly and readily absorbs medication
Treatment regions involving skin surfaces in frequent contact
Intertriginous areas
The apposition of two skin surfaces produces enhanced absorption
of drug
Areas of skin surfaces enclosed under tight clothing
(the diaper area)
Enhanced absorption of the agent due to the occlusive effect
of the garment
Topical corticosteroids
Washing the skin before corticosteroid application
Unnecessary
The medication applied in thin layers
Massaged daily into the skin
Advised directions for corticosteroid application in
the treatment course
Early application with extra medication per dose or more
frequent medication administrations
Not desired
A reduced frequency of application or a decreased amount
of medication as the disease process responds to therapy
can cause relapse.
Topical corticosteroids
Optimum application regimens
Not been determined in most dermatologic syndromes
The more potent agents from the steroid groups
Applied two to three times daily for 1 to 2 weeks followed by
a drug-free week
Additional therapy
Required as determined by the disease and by the particular
patient's response to the initial therapy
The Less potent agents
Applied three times daily for 2 to 4 weeks followed by a 7day steroid-free period.
Topical corticosteroids
Estimate the amount of topical corticosteroid to prescribe
according to the burn rule of 9's
Calculate the percentage of body surface area requiring therapy
Providing the amount of topical corticosteroid in grams for a single
application
In general, 9 g of topical steroid will cover 9 percent of the body
surface area in a thrice-daily application for 1 day
Description of topical corticosteroid amount to be dispensed
relative to the coverage area and duration of therapy
Tachyphylaxis of corticosteroids
Tachyphylaxis
The decrease in responsiveness to a drug as a result of
enzyme-mediated events.
Acute tolerance to the vasoconstricting ability in
relation to topical corticosteroids
Decreasing progressively over time after a topical steroid has
been applied.
As soon as 4 days into the treatment course in all potency
groups
Strategy to counter the development of tachyphylaxis
Interrupted application schedules
ex.) an initial thrice-daily application for 2 weeks, followed
by 1 week without using the drug and a repeat of the cycle.
스테로이드제 치료가 도움이 되는
주요 피부질환
Atopic Dermatitis
Toxic Shock Syndrome
Urticaria
Contact Dermatitis
Diaper Dermatitis
Erythema Multiforme
Pemphigus Vulgaris
Herpes Zoster
Exofoliative Dermatitis
Acneiform Eruptions
Seborrheic Dermatitis
Exogenous Photosensitivity
Disorders
Contact Dermatitis of the
Face
Alopecia Areata
Hand and Foot Dermatitis
Psoriasis
Lichen Simplex Chronicus
Human Scabies
Pediculosis Corporis
Venous Stasis Dermatitis and
Venous Leg Ulcers
Erythema Nodusum
Noninfectious Intertrigo
Candida intertrigo
항히스타민제 치료가 도움이 되는
주요 피부질환
Drug eruptions
Atopic Dermatitis
Urticaria
contact dermatitis
Erythema Multiforme
Contact Dermatitis of the Face
Lichen Simplex Chronicus
Human Scabies
Pediculosis Corporis
Venous Stasis Dermatitis and Venous Leg Ulcers
References
Tintinalli’s Emergency Medicine, 6th ed.
Internet web site
http://www.accessmedicine.com/content.aspx?aID=609483
Drug Information provided by Gold Standard, Inc. 2007
Marx: Rosen’s Emergency Medicine: Concepts and
Clinical Practrice. 6th ed.