Practice Flashcards
What are the five types of dermatological treatment?
1) surface treatment (insect repellent, sunscreen, topical anti microbial/fungal)
2) stratum corneum (solar keratosis, emollient therapy)
3) skin appendages (acne, depilatory, antiperspirant)
4) viable epidermis/dermis (anti-inflammatory, anaesthetic, antihistamine)
5) transdermal (HRT, opioid, Parkinson’s)
Examples of internal topical preparations?
Mucosal membranes, rectal, vaginal Bonjela Nystatin Clotrimazole Anusol
Advantages of topical delivery?
No first pass metabolism Controlled release More selective to target site Less side effects Easy to use Good compliance Avoid fluctuation in drug levels Efficacy with lower daily doses Easy to terminate drug action
Disadvantages of topical delivery?
Allergic reactions to active and excipients
Larger drug particles may not penetrate the skin
Only for drugs where smaller plasma concentrations are required
Enzymatic breakdown of some drugs in the skin
How do transdermal penetration enhancers act?
1) disruption of highly ordered structure of stratum corneum lipid
2) interaction with intercellular protein
3) improved partition of the drug, co-enhancer or solvent into the strain corneum
Examples of transdermal penetration enhancers?
Propylene glycol
N-methyl pyrrolidone (NMP)
Dimethyl sulphoxide (DMSO)
Laurocapram (azone)
Types of solid topical dosage forms?
Powder
Aerosol
Plaster
Types of liquid topical dosage forms?
Lotion Liniment Solution Emulsion Suspension Aerosol
Types of semi-solid topical dosage forms?
Ointment Cream Paste Gel Jelly Suppository
Ointment features?
Usually less than 20% water More than 50% hydrocarbons Greasier than other preparations Soften/melt at body temperature Translucent
Advantages of ointments?
Less skin sensitivities due to less preservatives
Good for moderate to severe dry skin
Good for night time application
Less regular applications needed
Disadvantages of ointments?
Some people don’t like the greasy feeling so can cause non-adherence
Can ‘grease’ clothes and bedding
Features of creams?
Semisolid that possesses a relatively soft, spreadable consistency
More fluid than ointments
Formulated as either water in oil or oil in water emulsions
White appearance due to scattered light from dispersed oil globules
Less greasy
Advantages of creams?
Less greasy so increased adherence
Can be used in weeping eczema
Disadvantages of creams?
More applications required
Features of lotions?
Light preparations with high water content
Oil in water emulsion
Advantages of lotions?
Spread easily
Quickly absorbed
Can use on hair areas
Can be used to deliver antibiotics, antifungals, corticosteroids etc
Disadvantages of lotions?
Poor moisturising properties
Must be shaken
Features of gels?
Semisolid systems
Consist of dispersion of small inorganic particles or large organic molecules in an aqueous suspension
Also use a gelling agent such as carbomer to thicken the colloidal dispersion
Non-Newtonian flow characteristics
Very high water content but are water insoluble
Can contain drug substances, cosolvents, anti microbial preservatives, stabilisers
Drug release rate depends of physical structure of the gel
What are emollients?
Smooth and soften skin by restoring the skin barrier
Semi-solids that contain no water (oil or grease based)
Can contain exfoliations (salicylic acid), antipruritics (lauromacrogols), lipids such as ceremides and cholesterol and antiseptics
How do emollients moisturise the skin?
Increase the amount of water in the stratum corneum in two ways:
Occlusion by trapping moisture into the skin it is best achieved by greasy emollients such as petrolatum products
Active movement of water from the dermis with low molecular weight molecules called humectants (urea, glycerine)
What are parabens?
Hydroxybenzoates Popular preservative found in creams Broad spectrum of anti microbial activity Colourless, odourless Stable Unexpensive But allergies in 1.2% of patients
What is lanolin?
Yellow, waxy substance secreted from sebaceous glands of sheep to waterproof their wool
Rarely cause reactions (hypoallergenic)
Counselling required for paraffin?
Flammable
What is sodium Lauryl Sulfate?
Surfactant and detergent
Partly water soluble and partly oil soluble this allows the water and oil to become mixed
Used in emollients for its thickening and emulsifying properties
Can be drying and may cause irritation
Advice when giving out an emollient?
Wash and dry hands and affected area
Maybe use a spatula to reduce microbial contamination or give a pump dispenser
Apply as frequently as possible and especially after bathing
Avoid bubble baths
Use as a soap substitute- either apply when wet or dry then wash off
Apply in the direction of the growing body hair
What is the recommended amount of emollient to use per week?
500-1000g per week
Half for a child
Cautions with bath oils?
Elderly and young children due to bath becoming slippery
What are adverse drug reactions?
An unwanted or harmful reaction that occurs after administration of a drug and is suspected or known to be to due to the drug
What percentage of hospital admissions are due to ADRs?
6-7%
ADRs occur in what percent of hospital inpatients?
10-20%
Implications of ADRs?
adverse effect on patients quality of life
Can cause patients to lose trust
Increased cost of patient care
Lengthen hospital stays
May mimic disease, causing unnecessary investigations
What does type A ADRs stand for?
augmented
What are type A ADRs?
Predictable Does related Morbidity high Mortality low Usually stops when the drug is withdrawn
Examples of type A ADRs?
Bleeding from warfarin
Antimuscarinic side effects from TCAs
Antimuscarinic ADRs mneumonic?
SLUMBAG Salivation, secretions, sweating (lack of) Lacrimation (lack of) Urinary retention Miosis Bradycardia, bronchoconstriction, bowel movement Abdominal cramps, anorexia GI upset
What do type B ADRs stand for?
bizarre
What are type B ADRs?
unpredictable
Rare
Often severe
Examples of type B ADRs?
anaphylaxis from antibiotics
Agranulocytosis from clozapine, carbimazole and carbamazepine
What do type C ADRs stand for?
Continuous
What are type C ADRs?
when the patient has been taking for a long time
Need to assess benefits vs risks of continuing treatment
Example of a type C ADR?
osteonecrosis of the jaw with bisphosphonates
What do type D ADRs stand for?
delayed
What are types D ADRs?
It can happen after the course of medication has been completed
Example of a type D ADR?
Tendon rupture with ciprofloxacin
What do type E ADRs stand for?
end of use
What are type E ADRs?
withdrawal symptoms
Example of a type E ADR?
Benzodiazepine withdrawal
Groups most vulnerable to ADRs?
Elderly Renal impairment Hepatic impairment Children Pregnancy Breast-feeding Women (due pharmacokinetics, immunology and hormones)
Frequency of a very common ADR?
More than 1 in 10
Frequency of a common ADR?
1-10 to 1-100
Frequency of an uncommon ADR?
1 in 100 to 1 in 1000
Frequency of a rare ADR?
1 in 1000 to 1 in 10,000
Frequency of a very rare ADR?
less than 1 in 10,000
What does frequency not known mean in regards to ADRs?
frequency is not defined by product literature, or the side effect has been reported from post-marketing surveillance data
Top 10 drugs that cause ADRs?
NSAIDs Diuretics Warfarin ACE inhibitors/ AII antagonists Antidepressants Beta-blockers Opiates Digoxin Prednisolone Clopidogrel
ADRs from NSAIDs?
GI bleeding Poetic ulceration Haemorrhagic cerebrovascular event Renal impairment Wheezing Rash
ADRs from Diuretics?
Renal impairment
Hypotension
Electrolyte disturbance
Gout
ADRs from warfarin?
GI bleeding
Haematuria
High INR
Haematoma
ADRs from ACE inhibitors/AII antagonists?
Renal impairment
Hypotension
Electrolyte disturbance
Angioedema
ADRs from antidepressants?
Confusion Hypotension Constipation GI bleeds Hyponatremia
ADRs from beta-blockers?
Bradycardia
Heart block
Hypotension
Wheezing
ADRs from opiates?
Constipation
Vomiting
Confusion
Urinary retention
ADRs from digoxin?
Symptomatic toxic levels
ADRs from prednisolone?
Gastritis
GI bleeding
Hyperglycaemia
Osteoporotic fracture
ADRs from clopidogrel?
GI bleeding
What drug reactions should be reported by the yellow card scheme?
Serious reactions from established drugs
All reactions from new drugs
What is pharmacovigilance?
Monitoring the use of medicines in everyday practice to identity ADRs
Assessing risks and benefits of medications
Providing information to healthcare professions to optimise safety
Monitoring the effect of any action taken
Drugs that increase the risk of falls in the elderly?
benzodiazepines Antidepressants Sedatives Antipsychotics Anticonvulsants Anticholinergics Opioids Antihypertensives
What kind of drugs require close monitoring?
those with a narrow therapeutic index
Drug interaction definition?
when the effect of one drug is changed by the presence of another drug, food, drink or an environmental chemical agent
Types of pharmacodynamic drug reactions?
interference with drug effects of receptor
Interference with a physiological control process
Additive or opposing physiological effects
What is serotonin syndrome?
increased stimulation of serotonin receptors through increased release, reduced reuptake of serotonin and increased stimulation of receptors
Symptoms of serotonin syndrome?
mental status changes GI disturbances Agitation Confusion Hallucinations Hyperthermia Tremor
Drugs that can cause serotonin syndrome?
Ondansetron Triptans SSRIs Mirtazapine Fentanyl Tramadol Cocaine St. Johns wort Legal highs
What are pharmacokinetic drug interactions?
When the presence of one drug increased or decreased the concentration of another
More difficult to predict
All ADME
What are absorption drug interactions?
Formation of insoluble complexes
Enhanced absorption
Examples of absorption drug interactions?
Alendronic acid has decreased bioavailability when taken with calcium
Rivaroxaban had increased absorption when taken with food
What are distribution drug interactions?
drugs that compete for the same transport proteins
Inhibition of efflux transporters
Examples of distribution drug interactions?
Verapamil affects P-gp efflux pumps, so less digoxin is transported back out. Increasing digoxin concentrations
Phenytoin and valproate compete for the same protein binding site, usually displacing phenytoin
Examples of drugs that commonly interact with CYP enzyme inhibitors and inducers?
warfarin Contraceptive pill Theophylline Corticosteroids Tricyclics Pethidine Statins
What do CYP inducers do?
Reduce the concentration of drugs that are metabolised by CYPs
Examples of CYP inducers?
CRAPGPS Carbamazepine Rifampin Alcohol Phenytoin Griseofulvin Phenobarbital Sulphonylureas
Why do CYP inhibitors do?
increase the concentration of drugs that are metabolism by CYPs
Examples of CYP inhibitors?
SICKFACESCOM Sodium valproate Isoniazid Cimetidine Ketoconazole Fluconazole Alcohol and grapefruit juice Chloramphenicol Erythromycin Sulfonamides Ciprofloxacin Omeprazole Metronidazole
Example of food/drink being a CYP inhibitor?
cranberry juice inhibits CYP2C9, which breaks warfarin down, leading to increased levels of warfarin
Grapefruit juice inhibits CYP3A4, which breaks down statins leading to increased exposure. This can lead to rhabdomyolysis
How can CYP induction cause toxic metabolites?
paracetamol is usually conjugated with glutathione to form a non-toxic metabolite
Once this is used up, paracetamol can conjugate with other compounds to produce toxic metabolites
Name a drug that can act as both a CYP inducer and inhibitor depending on the scenario?
Ritonavir
What is a sign?
It can be objectively observed by the healthcare professional
What is a symptom?
What is observed by the patient and cannot be directly measured
What is biomedical testing?
the area of biomedical science that is concerned with the analysis of body specimens
Types of biospecimen?
urine Blood Tissues Cells DNA RNA Proteins
Types of routine biomedical tests?
Microbiology Virology Haematology Coagulation Clinical biochemistry Toxicology Immunology/serology Immunohaematology Urinalysis Histopathology Cytopathology Electron microscopy Genetics TFTs Lipid profile
How can drugs affect biomedical tests?
in vivo In vitro (interference with analytical procedure)
Types of in vivo effects on biomedical tests?
such as raised LFTs or other tests due to drug side effects
Types of in vitro effects on biomedical tests?
Alteration of chemical reactions, cause of turbidity in the reaction system, interference with enzyme reactions, cross-reaction with antibodies, radioactive interference
What are the 12 standards for medical notes?
1) Should be available at all times during hospital stay
2) Every page should have name, identification number and hospital location
3) Standardised structure and layout
4) Documentation should reflect continuum of care (chronological)
5) Standardised proforma to document admission, handover and discharge
6) Every entry dated, timed (24hr clock), legible with name signed and printed. Alterations should be countersigned
7) Entries made as soon as possible
8) Should identify most senior professional present and consultant
9) Agreed transfer of care if consultant changes
10) Entry should be made everytime doctor sees patient. If no entry for 4 days (acute) or 7 days (long-stay) the next entry should explain why
11) Discharge summary should be commenced when patient is admitted
12) Clearly record advanced decisions such as refusing treatment, DNAR, consent
What are Korotkoff sounds?
Noises used to measure blood pressure manually. It is when the blood pressure cuff changes the flow of blood through the artery
What does NEWS stand for?
National Early Warning Score
What does a NEWS score take into account?
Respiratory rate Oxygen saturations (including if any supplementary oxygen) Temperature Systolic blood pressure Heart rate Consciousness
