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Chapter 5
The Skin and Dermatologic
Drug Therapy
© Paradigm Publishing, Inc.
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Chapter 5
Topics
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Anatomy and Physiology of the Skin
Sun Exposure, Aging, and Skin Cancer
Acne and Dandruff
Skin Infections
Hair Loss
Dermatitis, Eczema, and Psoriasis
Wounds and Burns
Adverse Drug Reactions on the Skin
Herbal and Alternative Therapies
© Paradigm Publishing, Inc.
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Anatomy and Physiology of the Skin
Integumentary System
• Is the dermatologic tissue that covers the body
• Includes the skin, nails, and hair
• Protects the body from harmful pathogens and harsh
substances
• Helps to regulate the body temperature
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Anatomy and Physiology of the Skin
The Skin
• Has three layers
 Epidermis
 Dermis
 Subcutaneous
tissue
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Anatomy and Physiology of the Skin
Epidermis
• Is the outermost layer
 Is made up of dead and dried cells generated from the
dermis (next layer down)
Dermis
• Is the living, functioning layer of skin
 Hair follicles and nail beds form, arteries and veins
circulate blood, and nerves provide sensation
 Melanocytes provide skin pigmentation
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Anatomy and Physiology of the Skin
Dermis (continued)
• Contains sweat, sebaceous, and ceruminous glands
 Sweat glands make watery secretions all over the body
 Sebaceous glands secrete oil to lubricate hair and skin
 Ceruminous glands in the ear canal release waxy
material
Subcutaneous Tissue
• Is the innermost layer made up of elastic fibers (called
fascia) and adipose tissue (fat cells)
• Thickness varies depending on the region of the body
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Anatomy and Physiology of the Skin
Skin Problems and the Pharmacy
• External skin is easy to examine in the pharmacy
• Pharmacists can inspect an area of the skin
 Determine if self-treatment is fine or the patient needs
to see a physician or dermatologist
• If patients have a skin problem, pharmacy technicians can
get involved
 Can help identify patients with likely problems
 Get the pharmacist to physically assess the problem
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Sun Exposure, Aging, and Skin Cancer
Two Types of Skin Aging
• Intrinsic aging (natural skin aging)
 Is the loss of collagen and elastin in the dermis
 Over time, glands make less oil resulting in dryness
 Subcutaneous tissue shrinks, skin thins, and sagging
occurs
• Extrinsic aging
 Is caused by external factors
Sun exposure (accelerates the loss of collagen and
elastin), air pollutants, smoking, and skin irritation
Lesions (skin injuries); genetic predisposition
possible
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Sun Exposure, Aging, and Skin Cancer
Skin Tumors
• Caused by constant sunlight exposure and oxidizing
chemicals that cause DNA mutation
• DNA damage can result in
 Benign tumors such as moles and skin tags
 Precancer of the skin such as actinic keratosis
 Three types of skin cancer
Squamous and basal cell carcinomas grow slowly
Melanoma is fast-growing; treat early to prevent
spreading and becoming life-threatening
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Sun Exposure, Aging, and Skin Cancer
ABCDs and the Pharmacy
• Pharmacists and technicians can help patients
 Understand how to identify signs of dangerous skin
lesions
• Signs of cancer are categorized into the ABCDs
 When patches of skin have any of these characteristics,
patient should be evaluated medically
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Sun Exposure, Aging, and Skin Cancer
Signs of Skin Cancer: ABCDs
Asymmetry
one half unlike the other half
Border irregularity edges are jagged, not smooth in shape
Color variation
Diameter
patches of tan, brown, black, red,
and/or white
larger than 6 mm or the top of a pencil
eraser
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Sun Exposure, Aging, and Skin Cancer
Drug Therapy
• Indications: limit sun exposure, prevent damage from
ultraviolet radiation, and treat damaged skin
• Ultraviolet radiation is strongly linked to skin cancer
 Treating damaged skin is less effective than limiting skin
exposure in the first place
 Patients frequently buy sunscreen and sun block
products in a pharmacy
• Products for skin damage such as actinic keratosis or for
skin cancer are usually applied in a physician’s office
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Sun Exposure, Aging, and Skin Cancer
Rating System for Sunscreens and Sun Blocks
• SPF
 Estimates the amount of resistance to burning that
products provide
 Example: An SPF of 8 means a person can spend 8
times longer in the sun than normal time to burn
• Patient skin type is based on exposure to unprotected sun
for 45 to 60 minutes
• Products rated 50 or higher are sun blocks
 Do not allow tanning to occur
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Sun Exposure, Aging, and Skin Cancer
Recommended Sunscreen Product Guide
Patient Skin Type
Suggested SPF Product
Always burns, rarely tans
20–30
Burns easily, tans minimally
12–20
Burns moderately, tans gradually
8–12
Burns minimally, tans well
4–8
Rarely burns, tans profusely
2–4
Never burns, deeply pigmented
None needed
© Paradigm Publishing, Inc.
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Acne and Dandruff
Acne
• Is the most common skin condition for which treatment,
either OTC or prescription, is sought
• Due to sebum overproduction (glands around hair follicles)
• Involves pimples, blackheads, and whiteheads
 Caused by pores and follicles clogged with oily material,
dead skin cells, and dirt
• Severe acne (nodular acne or acne vulgaris)
 Can cause deep cysts that permanently damage the
dermis
 OTC products used for mild acne
 Prescription drugs used for moderate to severe acne
© Paradigm Publishing, Inc.
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Acne and Dandruff
Rosacea
• Is categorized as acne, but is a chronic inflammatory
disorder in adults
 Causes redness, visible surface blood vessels, raised
bumps on face and cheeks
 Becomes worse with sun or extreme temperatures
Dandruff
• Is a malfunction of oil-producing glands around hair
follicles on the scalp; overproduction of sebum and cells
• Results in specks of skin in hair and on scalp; not harmful
© Paradigm Publishing, Inc.
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Acne and Dandruff
Drugs for Acne
• Mild to moderate acne
 Clean the area daily to prevent new blackheads and
pimples
• Repeated acne lesions
 Use OTC products like benzoyl peroxide
• Moderate to severe acne
 Requires prescription products
 Start with topical agents and progress to oral agents such
as oral contraceptives (for women) or antibiotics like
tetracycline
• Rosacea
 Use metronidazole or azelaic acid
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Acne and Dandruff
Topical Acne Agents
• Indications: mild acne; in combination with oral agents for
moderate to severe acne
• Mild acne mainstays are benzoyl peroxide and salicylic acid
 Benzoyl peroxide is a bleaching agent that promotes
cell turnover in follicles
 Salicylic acid is a keratolytic agent that breaks down and
peels of dead skin cells so they do not clog pores
 Available in facial cleansers, washes, and masks
© Paradigm Publishing, Inc.
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Acne and Dandruff
Topical Acne Agents (continued)
• Side effects: dryness, redness, burning, and flaking or
peeling skin
• Cautions: external use only
 Some are flammable and should be kept away from
heat
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Acne and Dandruff
Retinoids
• Are vitamin A derivatives
• Mechanism of Action: increase cell turnover in follicles,
which pushes clogged material of the pores
• Mechanism of Action (Acne Vulgaris): change cell
development and inflammatory processes to reduce
swelling and redness
• Indications: moderate to severe acne and fine line and
wrinkle reduction
• Indications of Oral Retinoids: severe acne or psoriasis
© Paradigm Publishing, Inc.
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Acne and Dandruff
Retinoids (continued)
• Topical Retinoids
 Side Effects: burning, peeling, dry skin, redness, and
itching
 Cautions: Do not use with antibiotics
• Oral Retinoids such as isotretinoin
 Severe Side Effects: depression, psychosis, pancreatitis,
high triglycerides, and hepatotoxicity
 Cautions: Isotretinoin cannot be used by women who
are or might become pregnant
Is prescribed and dispensed through a FDAapproved program called iPLEDGE
© Paradigm Publishing, Inc.
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Acne and Dandruff
Dandruff Products
• Active ingredients in most dandruff products are selenium
sulfide and pyrithione zinc; both available OTC in shampoo
• Coal tar shampoos also OTC; used in severe dandruff
• Ketoconazole, an antifungal is available OTC and
prescription
• Mechanism of Action: slow cell and oil production
 Reduces skin flaking and itching
• Severe Side Effects: dermatitis, photosensitivity, and
aggravation of prior skin conditions (acne or psoriasis)
© Paradigm Publishing, Inc.
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Your Turn
Question 1: A patient is picking up a prescription. She mentions
that a mole on her leg looks different now, because one side is
bigger than the other? What should the technician do?
Answer: The asymmetry could be a sign of cancer. The
technician should ask the pharmacist to talk to the patient.
Question 2: A male patient, age 15, has mild acne. What is the
likely treatment?
Answer: Benzoyl peroxide and salicylic acid are the first-line
therapies for mild acne.
© Paradigm Publishing, Inc.
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Skin Infections
Fungal Skin Infections
• Caused mostly by dermatophytes and Candida albicans, a
yeast
• Common types include ringworm, athlete’s foot, jock itch
• Use antifungals to treat fungal skin infections
Viral Skin Infections
• Herpes simplex virus, type 1 causes cold sores
• Herpes zoster causes shingles (reemergence of a systemic
viral infection that appears as painful skin lesions)
• Genital herpes is a sexually transmitted disease
• HPV causes genital warts that are linked to cervical caner
© Paradigm Publishing, Inc.
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Skin Infections
Bacterial Skin Infections
• Caused by overgrowth of Staphylococcus aureus
 Example: impetigo occurs typically in children and
causes pus-filled blisters to break and form yellow crust
• Localized infections of the superficial skin layers are
treated with topical agents
• Severe skin infections that spread to other soft tissues are
treated with systemic agents
© Paradigm Publishing, Inc.
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Skin Infections
Topical Antibiotics for Bacterial Skin Infections
• Indications: local skin infections like cuts, scrapes,
impetigo, and skin rash
 Mupirocin used for impetigo and rosacea
• Mechanisms of Action: varies depending on drug class
• Side Effects: burning, stinging, pain, rash, dry skin,
swelling, and redness
• Side Effects (used near the nose): headache, runny nose,
respiratory congestion, and sore throat
• Cautions: Keep away from eyes; external use only
© Paradigm Publishing, Inc.
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Skin Infections
Lice and Scabies Infestation
• Lice
 Are parasitic insects that use the human body as a host
 Feed on human blood, which causes intense itching
Head lice are passed through direct contact or by
sharing combs, brushes, or hats
Pubic lice (crabs) are passed through sexual contact
• Scabies
 Are parasitic insects that burrow into the epidermis
 Feed on cellular material, which causes intense itching
 Spread by skin-to-skin contact or sharing a bed
• Treatment for both is OTC; also wash clothing and bedding
© Paradigm Publishing, Inc.
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Skin Infections
Pediculicides and Scabicides
• Pediculicides
 Indication: lice
• Scabicides
 Indication: scabies
• Mechanism of Action: impair CNS of insects, causing death
• Usage: Spread and left on skin, then washed off
• Pyrethrin is a first-line drug (OTC) for head lice
• Permethrin is a first-line drug (OTC) for lice and scabies
 Side Effects: mild itching, burning, tingling, numbness,
rash, headache, dizziness, diarrhea, nausea, and
vomiting
© Paradigm Publishing, Inc.
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Skin Infections
Pediculicides and Scabicides (continued)
• Lindane (prescription)
 Indications: lotion used for scabies and shampoo used
for lice
 Side Effects: dermatitis, itching, headache, pain, and
hair loss
 Severe Side Effects: significant and possibly lifethreatening
 Cautions: Can cause seizures; do not use on infants or
children
 Administration: wear gloves and wash hands
• All pediculicide products for external use only
© Paradigm Publishing, Inc.
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Hair Loss
Two Major Types of Hair Loss
• Androgenic alopecia
 Is most common type affecting men and women (called
male-pattern baldness)
 Treated with minoxidil (OTC solution or foam) or
finasteride
Side Effects (rare): dermatitis, redness, and itching
Takes 4 to 6 months before results are seen
• Alopecia areata
 Is a chronic inflammatory disorder affecting hair
follicles and may cause total hair loss
 Treated with potent topical corticosteroids
© Paradigm Publishing, Inc.
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Dermatitis, Eczema, and Psoriasis
Dermatitis and Seborrheic Dermatitis
• Dermatitis
 Is itchy, inflamed skin caused by many factors
 Causes redness, dry flaky skin, raised or bumpy skin, and
pruritus (severe itching)
• Contact dermatitis
 Occurs from exposure to irritants or allergenic substances
 Causes rash; plants cause redness, itching, rash, blisters
• Seborrheic dermatitis (cradle cap)
 Is greasy, scaly skin area; sometimes red, brown, or
yellow
 Treatment is good hygiene, topical antihistamines,
anti-inflammatory agents, and moisturizers
© Paradigm Publishing, Inc.
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Dermatitis, Eczema, and Psoriasis
Atopic Dermatitis
• Is a chronic (not curable) condition that appears in
childhood and continues into adulthood; also called
eczema
• Not well understood; patients often have elevated IgE
levels in their blood
• Appears as dry, flaky, red skin that is very itchy
• Severe symptoms (exacerbation) cycle with remissions
• Common triggers are stress, skin irritants, and food
allergies
• Treatment is to moisturize skin well and topical
corticosteroids for flare-ups
© Paradigm Publishing, Inc.
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Dermatitis, Eczema, and Psoriasis
Psoriasis
• Is an immunologic condition affecting T cell activity in skin
• Appears on skin as well-defined plaques (patches) that are
raised, silvery or white, flaky, and pruritic
 Can appear as small or large, painful plaques anywhere
on body
• Severe symptoms (exacerbation) cycle with remissions
• Triggers are stress and exposure to environmental factors
that dry out skin
• Difficult to treat and may not respond well to drug therapy
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Dermatitis, Eczema, and Psoriasis
Diaper Rash
• Occurs most often in children wearing diapers and also in
incontinent adults wearing absorbent undergarments
• Caused by bacteria that enters damaged surface skin tissue
• Diaper rash products used for skin irritation and redness
• Various ingredients in OTC products used for diaper rash
 Eucalyptol (eucalyptus oil) for antimicrobial activity
 Zinc oxide, a drying agent
 Camphor or menthol to provide local anesthetic action
 Balsam of Peru for wound healing and tissue repair
 Talc or kaolin for moisture absorption
© Paradigm Publishing, Inc.
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Dermatitis, Eczema, and Psoriasis
Drugs for Dermatitis, Eczema, and Psoriasis:
Corticosteroids
• Are usually the first choice for dermatitis, eczema, and
psoriasis
 Starts with topical treatment and then oral
• Use immunosuppressants or immunomodulators if
corticosteroids do not work
• Calamine relieves mild itching from allergic reactions
• Topical corticosteroids
 Are anti-inflammatory agents that inhibit redness
swelling, itching, and pain in the dermal layer
 Start with OTC products then prescription if needed
© Paradigm Publishing, Inc.
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Dermatitis, Eczema, and Psoriasis
Drugs for Dermatitis, Eczema, and Psoriasis:
Corticosteroids (continued)
• Indications (Topical Corticosteroids):
 Use creams for moist or oozing lesions
 Use ointments (more potent) for dry, scaly lesions
 Creams, gels, and ointments are not interchangeable
• Side Effects: burning, itching, dryness, hair growth,
dermatitis, acne, hypopigmentation, and skin thinning
• Cautions: super-potent topical corticosteroid products
should not be used longer than two consecutive weeks
 Do not apply occlusive wound dressings
© Paradigm Publishing, Inc.
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Dermatitis, Eczema, and Psoriasis
Drugs for Dermatitis, Eczema, and Psoriasis:
Calcineurin Inhibitors
• Are immunomodulators used sparingly for a short time
• Mechanism of Action: inhibit T cell activation preventing
release of chemical mediators that promote inflammation
• Indication: severe eczema (when topical corticosteroids do
not work)
• Types: Pimecrolimus (Elidel) and Tacrolimus (Prograf,
Protopic)
• Routes: topical and oral
© Paradigm Publishing, Inc.
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Dermatitis, Eczema, and Psoriasis
Drugs for Dermatitis, Eczema, and Psoriasis:
Calcineurin Inhibitors (continued)
• Side Effects (common): burning, itching, tingling, acne, and
redness at the site of application
• Side Effects (other): headache, muscle aches and pains,
sinusitis, and flu-like symptoms
• Cautions: associated with increased occurrence of cancer
(skin cancer and lymphoma) and do not take with alcohol
(topical and oral)
© Paradigm Publishing, Inc.
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Dermatitis, Eczema, and Psoriasis
Drugs for Dermatitis, Eczema, and Psoriasis:
Vitamin D Analogs
• Are synthetic forms of vitamin D that regulate cell growth
and development of skin cells
 Indication: psoriasis
 Routes: topical or oral
 Side Effects: burning, itching, and redness
 Side Effects (less common): burning, itching, skin
irritation, color change at application site, skin thinning
• Caution: do not use for patients with too much calcium in
the blood (such as kidney stones)
© Paradigm Publishing, Inc.
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Wounds and Burns
Decubitus Ulcers (Pressure Sores, Bedsores)
• Are severe wounds involving tissue damage through the
epidermis and dermis
• Caused by constant pressure applied to an area of skin
• Appear where skin covers bony protrusions that receive
constant pressure when lying or sitting down
• Prevent by turning or repositioning patients every 2 hours
• Treat by cleaning and removing necrotic (dead) tissue
while the wound heals on its own
• Some drugs promote regranulation, the process of building
new skin layers over a wound area
© Paradigm Publishing, Inc.
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Wounds and Burns
Burn Wounds
• Are caused by heat and thermal injury or by electrical and
chemical sources
• Treatment and prognosis depend on the severity and
amount of body surface area affected
• Affected surface area is estimated by dividing the body
into sections, each representing 9% of the total surface
• Treatment at a burn center is needed for third-degree
burns over a significant portion of the body
• Patients with burns over 80% or more of their bodies are
not likely to survive long term
© Paradigm Publishing, Inc.
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Wounds and Burns
Burn Wound Staging
Degree
Damage
First-degree
burn
Surface epidermal layers damaged, causing
redness and possibly peeling, but no blisters
Seconddegree burn
Third-degree
burn
Epidermis and dermis skin layers damaged,
causing redness, blisters, swelling, and pain
Destruction of epidermis and dermis layers,
possible damage to tissue underneath.
Permanent scarring . Requires medical
treatment.
© Paradigm Publishing, Inc.
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Adverse Drug Reactions on the Skin
Adverse Drug Reactions on the Skin
• A couple of the most common reactions to medication
show up on the skin
• Pharmacists often counsel patients on these potential side
effects
• Skin rash is the most common sign of allergy
• Pharmacy technicians must make sure to ask and
document any drug allergies and the symptoms
 Important to maintain patient safety
© Paradigm Publishing, Inc.
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Your Turn
Question 1: Soon after taking a new drug, a patient develops
an itchy rash. What could have caused this to happen?
Answer: The patient might be allergic to the drug. A rash is
the most common reaction for a drug allergy.
Question 2: Topical corticosteroids come in various forms,
including ointment and cream. How is the purpose of the
ointment form different than the cream corticosteroid form?
Answer: Ointments are best for dry, scaly lesions. Creams
are best for moist or oozing lesions.
© Paradigm Publishing, Inc.
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Adverse Drug Reactions on the Skin
Photosensitivity
• Is a frequent side effect of many drug therapies
• Is excessive response to solar exposure where the skin
easily burns after a short time in the sun
• Avoid sunburns by using sun block and clothing
• Many drugs associated with photosensitivity
(see Table 5.9)
• Pharmacy technicians should apply warning label
© Paradigm Publishing, Inc.
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Adverse Drug Reactions on the Skin
Drug Allergy Rashes
• Rashes from drug allergies appear as urticaria (hives) and
pruritus (intense itching)
• Reaction often appears soon after taking a new medication
• Allergic reactions can progress in severity
• Anaphylaxis
 Is a severe and potentially fatal reaction to drug
therapy causing airway swelling and difficulty breathing
 Should stop drug use immediately
 Treatment is antihistamines, corticosteroids, and
epinephrine
© Paradigm Publishing, Inc.
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Adverse Drug Reactions on the Skin
Stevens-Johnson Syndrome
• Is rare skin reaction that can become life-threatening
• Starts as a localized rash that, if left untreated, spreads
deeper, causing layers of skin to slough off
• Results in severe infection and temperature problems
• Caused by specific drug therapies
Heparin-Induced Thrombocytopenia (HIT)
• Is a rare allergic reaction to heparin (an anticoagulant)
that can become life-threatening
• Diffuse red, pruritic rash and stop drug immediately
© Paradigm Publishing, Inc.
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Herbal and Alternative Therapies
• Topical skin care products and cosmetics
 Addition of various natural substances added as
moisturizers to creams and lotions
Lanolin, cocoa butter, and vegetable or seed oils
 Works to supply added oils and moisturize
 Vitamins E, A, and D are emollients added to
moisturizers
• Aloe vera
 Has healing and anti-inflammatory properties
 Used for mild psoriasis and burn wounds
 Concentrations in many OTC lotions and oil too low to
treat conditions or disorders
© Paradigm Publishing, Inc.
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Summary
• OTC topical agents and retinoids are used for acne, in
addition to daily cleansing
• Topical antibiotics are used for acne and impetigo
• Pediculicides are used for head, body, and pubic lice
• Topical corticosteroids and calcineurin inhibitors are used
for dermatitis and eczema
• Vitamin D analogs are used for psoriasis
• Some drug reactions such as allergies, photosensitivity,
and Stevens-Johnson manifest on the skin
© Paradigm Publishing, Inc.
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