Lecture 2 Dermatology Pharmacology and Prescribing Flashcards
Name licensing boards in the UK
MHRA
EMA
SMC
Define unlicensed
Not approved for use in the UK
Define off label
– A licensed medication that is being used for an unlicensed indication
– Paediatric use- does not have license for this use but is licensed
Define Specials
– unlicensed dermatological preparations
– Long history of use, no strong evidence base but clinically effective.
What are some causes of prescription errors
• Lack of knowledge
– About the patient, the medication, allergies
• Mistake writing/generating the prescription
• Poor communication
• No local or national guidelines
• Pharmacy/medicine info service
What is pharmokinetics
The effect of the body on the drug
What is pharmacodynamics
The effect of the drug on the body
Factors associated with poor adherence of drugs
- Psychiatric co-morbidities
- Slower acting agents
- Multiple applications per day
- Lack of patient education
- Cosmetic acceptability of treatments
- Unintentional non-adherence
What is topical therapy
Vehicle combined with active drug
Name factors that affect absorption
- Concentration
- Base/vehicle
- Chemical properties of the drug
- Thickness and hydration of stratum corneum
- Temperature
- Skin site
- Occlusion
What forms does vehicles come as
- Solution
- Paste
- Cream
- Spray powder
- Lotion
- Shampoo
- Gel
- Ointment
- Foam
- Paint
- Tape
Drugs used Topically
- Corticosteroid
- Chemotherapy
- Antibiotic
- Parasiticidals
- Antiviral
- Coal Tar
- Dithranol- effective treatment in psoriasis
- Anti-inflammatory
- Vitamin analogues
- Salicylic acid
- Topical immunodilators- JAK Inhibitors
What is the mechanism of Topical steroids
– Regulate pro inflammatory cytokines
– Suppress fibroblast, endothelial, and leukocyte function
– Vasoconstriction
– Inhibit vascular permeability
What is the finger-tip unit
- About 0.5 g
- Should treat area double the size of one hand
- Useful in young children
Side effects of topical steroids
- Thinning /atrophy
- Striae
- Bruising
- Hirsutism
- Telangiectasia
- Acne/rosacea/perioral dermatitis
- Glaucoma
- Systemic absorption
- Cataracts
What are Retinoids
Systemic treatment
• Vitamin A analogues
– Normalise keratinocyte function
– Anti inflammatory and anti cancer effects
What retinoid is used to treat acne
Isotretinoin (1 month to eave system)
What retinoid is used to treat Psoriasis
Acitretin (takes 3 years to leave system)
What retinoid is sued to treat cutaneous T cell lymphoma
Bexarotene
What retinoid is used to treat Hand eczema
Alitretinoin
Side effects of Retinoids
– Cheilitis(dry lips) and xerosis (dry skin)
– ↑transaminases, ↑triglycerides
– Rarely psychiatric, eye, bone side effects
Name Immunosupressants
- Oral steroids
- Azathioprine
- Ciclosporin
- Methotrexate
- Mycophenolate mofetil
Precautions when using immunosuppressants
• Risk of malignancy and serious infection
• Need regular blood test monitoring, in particular
– FBC (esp in methotrexate and azathioprine)
– Renal function (esp ciclosporin)
– Liver function (esp methotrexate)
– Sun protection
Suffix ‘cept’ means
It is a receptor fusion
Suffix ‘mab’ means
monoclonal antibodies
‘zu’ in biologics means
Humanised
‘ix’ in biologics means
Chimeric
‘u’ in biologics means
Fully human
‘li/I’ in biologics means
Immodulator
What targeted treatments can be used to treat melanoma
Biologics:
• Vemurafenib
• Dabrafenib
– Immunotherapies
• Ipilumumab
• Pembrolizumab