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Prescribing in Dermatology No recording of the slides please. You will receive handouts. PRESENT ATIONOVERVIE W • Treatment modalities • Cover the principles of topical therapy • A note on topicalcorticosteroids • Systemic treatments in dermatology • Brief notes on the management of: • Acne • Psoriasis • EczemaTREA TMENTMODALITIES Treatment modalities for skin disease can be broadly categorisedinto: • Medical Therapy (Topical and systemic treatments). • Physical Therapy(Cryotherapy, phototherapy, photodynamic therapy, lasers and surgery).MEDICAL THERAPYROUTES OF ADMINISTRATION ORAL | TOPICAL PARENTERAL • Directly deliver treatment to the affected areas. • Systemic therapy is used for • Reducessystemic side effects. • Suitable for localised and less severe extensive and more serious skin conditions. skin conditions, if the treatment is ineffective • Consist of active constituents which topically or if there is systemic are transported into the skin by a involvement. base or ‘vehicle’. • Disadvantage - causes • Active ingredients include: steroids, systemic side effects. tar, immunomodulators, retinoids, and antibiotics. TOPICALFORMULATIONS Ointments Semi-solid vehicles composed of lipid, such as white soft paraffin BP (petrolatum). Contain fewer preservatives than other vehicles. Occlusive and emollient properties. Creams Semi-solid emulsions containing both lipid and water. Emollient, lubricant and mildly occlusive. Pastes Semi-solid preparations containing a high proportion of finely powdered material such as zinc oxide or starch. Occlusive, protective and hydrating. Lotions Liquid formulations, usually simple suspensions or solutions of medication in water, alcohol or other liquids. Suitable for treating the scalp and other hairy areas of skin. Gels Thickened lotions. Suitable for treating the scalp and other hairy areas of skin. Powders Occasionally used to deliver drugs such as antifungal agents applied to the feet. Paints Liquid preparations which are usually applied with a brush to the skin or mucous membranes. Dressings Impregnated dressings e.g. bandages containing ichthammol or zinc oxide, or tapes containing topical steroid.GENERALPRINCIPLES • Prescribing topical medication requires careful consideration of several factors to achieve optimal results. • Whenprescribing itisnecessary to specify the concentrationofthe active ingredient,the vehicle and the frequency of application. • The patient also needs advice on the quantity to be used , where it should be applied and often further explanation about timing of application in relation to bathing and other treatments. Duration is important, as well as potential side effects such as irritant or allergic reactions. • As a rule, acutely inflamed skin is best treated with bland preparations that are least likely to irritate. • Moist or exudative eruptions are treated with lotions or creams. • Dry skin responds well to ointments.FREQUENCY OF APPLICATION • Emollients should be applied frequently enough to maintain their physical effect which may require severalapplications a day. • The pharmacological actions of a drug may persist long after it has left the surface of the the intensity of a treatment, especially when you can’t use a lower concentration or less potent agent. QUANTITYTO BE APPLIED • Should be specified when prescribing. • Explain how much of the active ingredient is needed for effective treatment. There can be a tendency, especially with topical steroids, for patients to be overcautious in their interpretation of the advice to ‘apply sparingly’, which is found in the instructions. Minute quantities are rarely effective. • ‘Fingertip units’ are a useful guide for topical corticosteroid application, and this is the amount of cream squeezed out of a tube onto the fingertip. • In general emollients should be applied more liberally. The quantity of cream in a fingertip unit varies with The amount of cream that should be used varies with age: the bodypart: Adult male 1 fingertip unit One hand apply 1 fingertip unit provides 0.5 g One arm apply 3 fingertip units Adult female 1 fingertip unit One foot apply 2 fingertip units provides 0.4 g Child aged 4 years approximately 1/3 of adult amount One leg apply 6 fingertip units Face and neck apply 2.5 fingertip units Infant 6 months approximately 1/4 to 1 year of adult amount. Trunk, front and back 14 fingertip units Entire body about 40 units.TIMING OF APPLICATION • Leave a suitable amount of time between emollient and active agent. This avoids dilution of the active medication and prevents spread over areas of skin where it is not required.POTENTIAL HAZARDS • Localised irritant or allergic reactions. • All topically applied drugs are absorbed to some degree, but systemic side effects are rare. • Absorption varies considerably depending on the region of skin being treated (absorption greatest from the genital area and least from the soles and palms). • Paraffin-based ointments are flammable, which is a particular risk in smokers.A NOTE ON TOPICAL CORTICOSTEROIDS • Corticosteroid hormones are formed in the cortex of the adrenal glands. • Twoeffects: • Mineralocorticoid. • Glucocorticoid. • Large amounts of corticosteroids in the body will suppress immune system activity and produce an anti-inflammatory effect. • Mode of action: • Enzyme inhibition • Suppressing the formation of prostaglandin and leukotriene inflammatory mediators . • Decrease histamine release from basophils . • Suppress the inflammation and allergic/immune responses . • Side effects: Hyperglycaemia, diabetes, muscle atrophy,paper thin skin, ‘moon-face’and ‘buffalo-hump’, increasedsceptibility to infection, oedema, hypernatraemia, hypokalaemia, hirsutism.TOPICALCORTICOSTEROIDS • Potencyof topical corticosteroidsvary. • Mild and moderately potent topical corticosteroids are rarely associated with side effects. • Systemicabsorption can be increased in certain situations. • Thinning of the skin and prominent blood vessels are the most common side effects. • Only mild corticosteroidsshould be applied to the face. • Rebounderythroderma can occur if a treatment is stopped abruptly.TOPICALCORTICOSTEROID PREPARATION POTENCY MILDLY POTENT MODERATELY POTENT POTENT VERY POTENT Hydrocortisone Clobetasone Beclomethasone Clobetasol Alclometasone Betamethasone Halcinonide Fluocinonide Mometasone Fluocortolone Fluticasone Flurandrenolone Diflucortolone Halcinonide Desoxymethasone Fluocinonide TriamcinoloneSYSTEMICTHERAPY • Used for extensive and more serious skin conditions, if the treatment is ineffective topically or if there is systemic involvement. • Disadvantage: systemic side effects. • In dermatology we frequently use: o Antihistamines, Systemic glucocorticoids, systemic retinoids, Antimalarial agents like Hydroxychloroquine, Methotrexate, mycophenolate Mofetil, Antimicrobial drugs, Biological therapies, IVIG.MANAGEMENTOF ACNE Goals: 1. Alleviate symptoms 2. Clear existing lesions 3. Limit disease activity by preventing new lesions forming as well as scars developing 4. Avoid negative impact on quality oflife Therapy is determined by severity and extent of disease but should be guided by other factors such as duration, response to previous treatments, predisposition to scarring, post -inflammatory erythema and pigmentation, as well as patient preference, lifestyle and treatment cost. NB: Treatment needs to be continued for at least 6 weeks to produce effect. COMEDONAL ACNE First Line Second Line • Topical retinoid • Fixed dose combination clindamycin and BPO • Azelaic acid • Fixed dose combination adapalene and BPO • Combined oral • BPO • Fixed dose combination clindamycin- contraceptive pill tretinoin gel MILD-TO-MODERATE PAPULOPUSTULAR ACNE First Line Second Line • BPO OR • Topical retinoid OR • Fixed dose combinations • Systemic antibiotic ± topical • Adapalene + BPO OR retinoid • BPO + clindamycin • Combined oral contraceptive pills in females if not contraindicated SEVERE ACNE First Line Second Line • EU directive suggests systemic antibiotics plus BPO ± topical retinoid. • Systemic antibiotic ± • If poor prognostic factors and topical retinoid + BPO. severe disease consider oral isotretinoin as monotherapy early in the disease course. ISOTRETINOIN Dose Up to 1.0 mg/kg per day taken with fatty foods for 4 –6 months. Duration Adjusted to give at least 90% clearance of acne, followed by 4 –8 weeks of consolidation. Mode of action Reduces sebum production, influencescomedogenesis, lowers surface and ductal P.acne,s as anti-inflammatory properties. Indications Severe acne that has failed to respond to antibiotic therapies. Resistant rosacea. Most important things to Women of childbearing potential must be counselled about teratogenicity; must not become counsel patient about pregnant during or for 1 month after treatment. Psychiatric referral if significant depression. Do not donate blood during and for at least 1 month after treatment. Avoid waxing/dermabrasion during and for 6 months after. Sun protection (more likely to burn). Intolerance of contact lenses. Contraindications Inability to attend for monitoring, pregnancy/breast-feeding, hepatic impairment, uncontrolled hyperlipidaemia, hypervitaminosis A, airline pilots, Allergy to soya bean. Side effects Dryness of nasal, buccal, lip or conjunctival mucous membranes, epistaxis, nail fragility, paronychia, teratogenic, very rarely suicide reported, arthralgia, myalgia, photophobia, impaired night vision, headaches, raised lipids, hepatitis, anaemia, neutropenia. Baseline investigations Pregnancy prevention programme as per local guidelines, Liver enzymes and lipids. Monitoring Liver enzymes and lipids repeated at 1 month and 3-monthly during treatment. Monthly requirements pregnancy test and 5 weeks post treatment in women of childbearing potential. Mood assessed each visit.MANAGEMENTOF PSORIASIS • General measures - avoid known precipitating factors, emollients to reducescales. • Mild plaque psoriasis without psoriatic arthritis: • First line: Coal tar, dithranol, potent topical corticosteroid or vitamin D analogue often combined with corticosteroid, topical retinoids,keratolyticsand scalp preparations. • Second line: Phototherapy - Local narrow band UVB or PUVA, excimer laser. • Moderate to severe plaque psoriasis without psoriatic arthritis: • First line: Narrow band UVB or PUVA. • Second line: Acitretin, apremilast, ciclosporin, fumaric acid esters (where available), methotrexate. • Third line: Biological agents (e.g. etanercept, adalimumab, ustekinumab). • Moderate to severe plaque psoriasis with psoriatic arthritis: • First line: apremilast, methotrexate. • Second line: Biologics. • Third line: Combination therapy.MANAGEMENTOF PSORIASIS • Coal tar: • Coal tar has anti-inflammatory and anti-scaling properties. • Its use may be limited because it stains skin and clothes, is messy to apply, and has a strong smell . • Coal tar sometimes causes irritation, contactallergy, and sterile folliculitis . • Highlight the importance of shampoo formulations reaching the scalp.MANAGEMENTOF PSORIASIS • Calcipotriol: • Vitamin-D derivative. • Often used as first-line therapy for plaque psoriasis. • Contraindications include calcium metabolism disorders and hypercalcaemia. • Use with caution in generalised pustular, guttate and erythrodermic psoriasis where there is an increased risk of hypercalcaemia . • May cause irritation when applied to sensitivesites. • Avoid excessive sunlight. • Monitor serum calcium and renal function before commencing calcipotriol and 3- monthly following this if maximum doses may be exceeded.MANAGEMENTOF ECZEMA • General Measures : o Education: Effective education facilitates effective treatment . o Skin irritants: Where possible avoid triggers that can directly inflame the skin, including fabrics, chemicals,humidity, and dryness. o Food: Food allergies may exacerbate atopic dermatitis, but avoidance diets do not cure the problem. Avoidance may exacerbate atopic dermatitis. Food allergy testing is needed if there is concern of anaphylaxis . o Psychologicalsupport: Counselling and cognitive behavioural therapy can be beneficial . • Frequent emollients +/ - bandages and bath oil/soap substitute. • Topical steroids for actir es. • Topical immunomodulato ers.(tacrolimus,pimecrolimus) for maintenance therapy as steroid-sparing agents. • Oral therapies - antihistamines for symptomatic relief. • Antibiotics (e.g. flucloxacillin) for secondary bacterial infections. • Antivirals (e.g. aciclovir) for secondary herpes infection.EMOLLIENTS FOR ECZEMA • The selection of an emollient is based on eczema severity, degree of xerosis, and the patient’s preference. • Ideal emollient should be pleasant to use, optimise skin appearance, and restore theskin barrier. In addition, it should contain only a few ingredients and ideally avoidirritants or allergenssuch as fragrances. • Emollients come in a variety offormulations. • Leave-on emollients are applied directly to the ski. • Vary in consistency from light to heavy. • Lightpreparations, such as creams and lotions, are quickly absorbed owing to their highwater content but require more frequent application than thicker ointments.Suitable for a broad area of application. • Heavy preparations (ointments) have an occlusive, protective, longer lasting effect due to their higher oil content, but are usually less cosmetically acceptable due to their oily appearance • Typicallypatients withchronic eczema will prefer to use a heavy preparation, especially when applied to a small area. • Soap can be used on body folds but should be completely rinsed off. • Emollient soap substitutes are preferred when washing the rest of thebody. THANK YOU FOR LISTENING FeedbackForm Any questions, please email.