DERMATOLOGIC
THERAPY
Dr.MOHAMED NASR
Lecturer Of
Dermatology & Venereology
I. Topical therapy

In medicine, a '''topical''' medication is applied to
body surface such as the skin or mucous
membranes.
CLASSES OF TOPICAL
PREPARATIONS
Solutions
These are a powder dissolved in a base of water
or alcohol.
Lotions

Lotions are similar to solutions but thicker and
more emollient. They are usually oil mixed with
water.
Shake lotions

These are suspensions of fine powders in oil
mixed with a water-based solution. The mixture
separates with time so it needs to be shaken well
into suspension before usage.
Emulsions

These are oil in water emulsions, they are more
stable than shake lotions and less drying than
lotions
Cream (hydrophilic ointment)
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A Cream is a semisolid compound of oil (or
petrolatum) and water in approximately equal
proportions stabilized with a detergent such as
sodium lauryl sulphate.
Cream is thicker than lotion.
It has a good penetration power of the stratum
corneum.
Ointment

An '''ointment''' is a homogeneous, viscous, semisolid preparation of the active ingredient in a
greasy, thick oil or white soft paraffin
(petrolatum) with a concentration of oil 80% and
water 20%.
Gel
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Gels are thickened aqueous lotions.
They are often a semisolid emulsion of high
molecular weight polymers in an alcohol base.
Gels and lotions are especially suitable for
treatment of the scalp and other hairy areas as
well as body folds.
Collodions

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They are liquid preparations consisting of
cellulose nitrate in an organic solvent.
They evaporate rapidly to leave a flexible film
holding the medicaments in contact with skin.
Transdermal patch

A method of delivering a drug by diffusion to the
skin.
Powder

Powder is either the pure drug by itself or the
drug is mixed in a carrier such as corn starch.
Solid

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Some medications are placed in a solid form such
as deodorants, antiperspirants and astringents.
Some solids melt when they reach body
temperature e.g. rectal suppositories.
Tape

Topical applications may be used under occlusion
by a tape. This greatly increases the potency and
absorption of the topical agents.
Paste
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Paste is a semisolid preparation, thicker and drier than an
ointment.
Protective fatty paste is a suspension of a powder such as
zinc oxide or starch in a greasy ointment base. It is greasy
and water insoluble. It acts as occlusive, protective and
hydrating agent.
Drying paste (cooling paste) is a mixture of powder with
liquid so it is non greasy and water miscible and easy to
apply and remove. It acts as a drying and soothing agent.
1-Topical steroids:
Indications:
 Dermatitis
 Lichen planus
 Alopecia areata
 DLE
 Psoriasis
Side effects:
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Epidermal atrophy.
Impaired wound healing.
Persistent vasodilatation and telangiectasia.
Hypopigmentation (melanocyte inhibition).
Striae due to collagen synthesis inhibition.
Acneiform eruption.
Suppression of inflammatory signs of infectious cases as impetigo
contagiosa followed by marked exacerbation of the condition after
stoppage of steroids.
Scabies and fungus infection clinical pictures may be modified by the
use of steroids leading to scabies incognito and tinea incognito.
Indications for intralesional steroid
injection
1.
2.
3.
4.
5.
6.
Keloid
Hypertrophic lichen planus
Alopecia areata
Nodulocystic acne
DLE
Post scabietic nodules
2-Topical retinoids:
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Tretinoin 0.1% and isotretinoin 0.05% cream and
gel are used for acne, melasma and solar lentigenes.
They may cause dermatitits and irritation.
Adapalene 0.1% gel is less irritant and better
tolerated.
II.Systemic therapy
Antihistamines
Indications: itchy skin diseases as:
 Generalized pruritus
 Atopic dermatitis and other types of eczema
 Urticaria and angioedema
 Scabies
 Lichen planus
Types of antihistamines :
1- H1 receptor antagonists
 First generation (sedation & atropine like effect).
 Second generation (do not cross the blood brain
barrier, so do not cause drowsiness, they also have
longer action).
2-H2 receptor antagonists
 They are antagonists for H2 histamine receptors,
found principally in the parietal cells of the
stomach.
 They can be combined with H1 antihistamines in
chronic urticaria
Systemic steroids
Indications:
 Acute anaphylactic reactions.
 Autoimmune diseases: pemphigus, pemphigoid, Behcet's.
 Connective tissue diseases: SLE, Dermatomyositis, systemic
sclerosis.
 Lichen planus: oral ulcerative lichen planus, destructive nail
involvement and generalized lichen planus.
 Disseminated or extensive cases of eczema.
Antimalarials

They are indicated in: lupus erythematosus
especially DLE and solar urticaria.
Dapsone
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It is indicated in leprosy and acne conglobata.
Ivermectin
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It is effective against Sarcopts scabiei.
Dose in scabies is 200 μg / kg repeated in 7 to 14 days.
Side effects: (rare and usually minor)
Transient tachycardia
Flushing
Nausea
Diarrhea
Skin rash
Oral retinoids

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Oral retinoids are synthetic derivatives of Vitamin
A (retinol).
They have a role in normalization of skin
differentiation and keratinization.
Etretinate:
 It is the parent of retinoids.
Acitretin:
 It results from hydrolysis of etretinate and is now superior
to it.
 It is used in extensive forms of psoriasis especially
erythrodermic and pustular forms.
 It is also used in disorders of keratinization as icthyoses,
palmoplanter keratoderma, PRP and lichen planus.
 The dose ranges from 0.25: 1 mg/ kg per day.
 It is best taken after a meal because it needs fat to be
absorbed through the gut wall.
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Isotretinoin: it is effective in severe and resistent
forms of acne as nodulocystic acne and cases not
responding to ordinary treatments.
Bexarotene: for cutaneous T cell lymphoma.
Side effects of retinoids:
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The most serious is teratogenecity, so pregnancy should be
absolutely prevented for at least 2-6 months after stoppage
of the drug.
Headache,lethargy, anorexia, nausea and vomiting.
Benign intracranial hypertension (with isotretinoin).
Dryness of lips, nose and eyes.
Skeletal hyperostosis in prolonged therapy.
Elevation of liver enzymes.
Changes in serum lipids and elevation of triglycerides and
cholesterol.