OD Flashcards
1
Q
Diagnostic Dyes (medical devices)
A
Fluorescein Sodium
Rose Bengal
Lissamine green - unverified legally
2
Q
Fluorescein - Uses, mode, AR, preparation
A
1) Goldmann, cL, corneal integrity, tear BUT
2) Ph indicator
3) rare
4) Single dose Minims 1mg (1&2%)
3
Q
Lissamine Green - Uses, mode, AR, preparation
A
1) Dry eye
2) stains devitalized cells
3) Less than Bengal
4) paper strips 1.5mg
4
Q
Bengal Rose (Uses, Mode, AR, Preparation)
A
1) Keratoconjunctivits sicca
2) stains devitalized cells
3) stings and stains skin
4) paper strip 1.5mg
5
Q
Paper strips as vehicles (advantages)
A
Economy and storage
not aqueous, sterile
when eye vunerable
6
Q
Why fluorescein?
A
visible in low conc
7
Q
Topical Anaesthesia uses, mode of action, onset and recov time, AR, preps
A
1) applanation tonometry, lenses; superficial FB, gonioscopy, ultrasound
2) blocks increase in nerve permeability, to na+ ions, no depolarization
3) 30 seconds: 25/30 mins
4) toxicity & allergy
5) minims -
- proxymetacaine0.5%, - stings signif less and store -in refrigerator
- oxybruprocaine0.4% - stings signif
- tetracaine 0.5% and 1% - minor surgery
- lidocaine 4% +0.25% fluorescein- stings and surgery onset 1 min, recov 20-30mins
8
Q
Re-usable ophthalmic devices, steps
A
1) rinse in water and saline for irrigation >30 secs
2) clean surfaces with detergent >30 secs
3) immerse in na hypochlorite 1% for 10 mins
4) rinse in 3 changes of water for irrigation >10mins
5) shake, dry, store
6) conventional disinfection
9
Q
Why topical Anaesthesia?
A
inhibit reflex tearing
facilitate corneal absorption
10
Q
Dry eye, what do we do?
A
give: povidone, theratears, actimist spray, rohto
refer severe cases and Sjorgens syndrome
11
Q
Importance of adequate aq production and drainage of aqueous
A
1) maintain tear nutrients
2) moisten the surface
3) mechanical flushing system
12
Q
Mucin deficiency, effects on tear film and why?
A
- Unstable tear films, abnormal tbut
- reduction in goblet cells
13
Q
Importance of lipids
A
bacterial release of lipase to hydrolyse reactions
decreases rate of spreading
14
Q
Impaired lid function
A
Exposure keratitis
poor mucous distribution
15
Q
Lubricants
A
Acetylcysteine Carbomers Carmellose sodium hydroxyethycellulose hypromellulose liquid paraffin macrogols paraffin, yellow and soft polyvinyl alcohol nacl na hyaluronate soya bean oil
16
Q
Tear substitutes, types of Carbomers and properties
A
most prescribed tear substitute after hypromellulose Carbomers: polymer of acrylic acid reduce natural elimination of tears retention time 7 x pva drops 4x a day not 20 protects in sleep less benzalkonium allergy risk
17
Q
Contact lens product categories
A
- Designer Molecule Disinfectants - (biocides) H2O2, 3%, req neutralisation Polyhexamide, common constituent Polyquaternium 1 Alexidine, Amidoamine
- Surfactant cleaner - poloxamer, removes bacteria,
- Chelating agent - EDTA removes calcium and protein
- Demulcents - water soluble polymers
- Propylene Glycol - enhanced water retention on hydrogel lens surface
- Tonicity and Buffering agents - phosphates, borates & citrates, resist pH change
18
Q
Ocular first aid advice
A
WHAT TO HAVE
- Keep calm
- Auxiliary staff recognising important sx
- Record is essential
- Drugs used - fluorescein, saline, tear subs, anti infective, allergy
BE PREPARED FOR
- superficial FB - evert, sketch staining pattern and record advice give. If embedded, refer. Check both eyes
- Harmful chem agents - lime and alkali DANGEROUS AS NOT SELF LIMITING, irrigate, refer if signif damage, but H/S usually protects
- AR to instillation, Acute ocular pathology
19
Q
Most likely presentations of FB
A
Sports - cycling, running, tennis DIY - drills, sanding, gardening Everyday tasks - elec toothbrush Corneal epitheliopathy - finger nails The Lost Contact Lens...
20
Q
Optometric Drug Use categories
A
Extraocular Intraocular Cycloplegia, mydriatics miotics
21
Q
Muscle Pathways: Cillary, Sphincter, Dilator
A
Cillary
- CILLARY & SPINCTER.
PARASYMPATHETIC
acetylcholine - Muscarinic. Via Cholinegic (neuro - effector)
DILATOR AND MULLERS MUSCLE SUPERFICIAL CONJUNCTIVAL VASCULATURE
SYMPATHETIC
Nor adrenalin - Alpha 1. Via Adrenergic (neuro - effector)
alpha 2 receptors on pre synaptic nerve
22
Q
Which drugs effect which receptors
A
- Cycloplegia (antagonist) - Block muscarinic (CYCLOPENTOLATE)
- Mydriasis - Block Muscarinic (TROPICAMIDE) and stimulate Alpha 1 (PHENYLEPHERINE)
- Miosis - Stimulate Muscarinic (PILOCARPINE) and block Alpha 1 (THYMOXAMINE)
23
Q
Pharmacological Group
A
- Parasympathomimetic - Stimulate ACh, accom and miosis, cholinomimetic esterase’s & alkaloids. PILOCARPINE
- Anticholinesterases - Increase ACh, accom and miosis, indirect muscarinic, reversible (physostigmine) and irreversible (ecothiophate)
- Antimuscarinics - ACh antagonist,
Natural - atropine (as), hyoscine
Synthetics - cyclopentolate & tropicamide(EL), Homatropine (AS) - Sympathomimetics - cause adrenergic action. Cause mydriasis (widening)
Catecholamines (hormones in body)
Non - catecholamines - phenylephrine, naphazoline, xylometazoline, brimonidine, apraclonidine - Adrenergic blockers - block adrenergic receptors
miosis, ptosis
Thymoxamine
24
Q
The aim of cycloplegics? and how does it work? Types?
A
Estimate static refraction by eliminating accommodation as a variable.
25
When to use Cycloplegics (signs) and sx
```
Hyperopia, FH
unstable ESOP
anomalies of AC/A
malingering
Refraction surgery
```
Accom spasm,
asthenopia,
visual conversion reaction
26
Advantages and Disadvantages of Cycloplegia
Ad
full static rx, assoc mydriasis useful
DIsad
unnatural, aberrations, glare disability, toxicity
27
Alternatives to cycloplegia and ensure
Fogging, Mohindra, Auto-rx
```
Dosage,
progression,
retinoscopy,
pre and post cyclo - D & N WHILE CYCLO, JUST D
prescribing, AR
```
28
Cyclopentolate, action n recovery times
Main cycloplegic 1%, 2 drops of 0.5%
action time - c 40m m 20m
Recovery times - c24hr m 48hr
29
Tropicamide, who, action n recov times, AR?
```
Mydriatic normally but cycloplegic for olders
and is rapid
0.5 and 1%
Action time - c 20m M 15m
recovery - c 3hr M 5hr
peak period 10 -15 mins
toxic reactions rare
```
30
Atropine and Homatropine
Rarely used in GP, sx of poisoning
| young child with no BV
31
Application of Mydriatics
Anti muscarinic, sympathomimetics
General - unsure about cause, stereo needed, risk of detachment
Specific - diab, cataract, monocular px
Instrumentation - ret camera, mono bin, slit lamp
32
CN of mydriatics, risk and how to minimalize
1) consent, measure diameter before, monitor change, glare sensitivity
2) 1/5000 ACG, risk when driving and cycling. Risk of missed pathology outweighs risk of dilation
3)
- IOP before and after
- angle
- sx of sub acute attack of closed angle glaucoma
- management of acute attack
33
Sympathomimetics and synergistic combinations
1)
- phenylephrine
- relatively slow action
- pupil reactions retained
2)
- can reduce cycloplegic effect
- rapid action and recovery
- use of topical anaesthesia
34
Miotic drugs, what do they do, categories
Causes constriction of pupil
assists recovery, rarely used in practice
Categories - parasympathomimetic, anticholinesterases, adrenergic blockers
Parasympathomimetic - Pilocarpine, 1% ,2% ,4%
- POM - AS)
- CI - phenylephrine
- limited use for POAG
Anticholinesterase
-Physostigmine, not available in practice, very pronounced miosis
ecothiosulphate
```
Adrenergic -
Thymoxamine (AS), alpha 1 adrenergic antagonist.
-refrigerate
-stings a lot
-Conjunctival ptosis
```
35
What is infection
1)Detrimental colonization by foreign species
2)this pathogen uses the bodies resources
main ones - bacteria, fungi, virus. Optoms do bacteria
Mechanisms of action
- > Antibacterial
- > Antiviral
- > Antifungal
36
Anti viral and Antifungals
Only SP and IP
- Antivirals (SP & IP)
aciclovir (POM)
ganciclovir (POM)
- Antifungals (SP & IP)
Specialist centres
37
Anti bacterial
superficial infection, usually staphyloccoci, usually
incorporates a steroid and broad spectrum
EL -
- Chloramphenicol - eye infections. Inhibit protein synthesis, binding to 50s subunit
CI - pregnant, hypersensitivity, bone marrow
disorder
AR - aplastic anemia
Minims.
```
- Fusidic acid - protein synthesis inhibitor for eye
infection.
CI - Hypersensitivity
AR- transient stinging
Ointment
```
- Propamidine isetionate - Modify DNA uptake, minor eye infections
CI - hypersensitivity
Ointment - Golden eye
AS -
Amino glycosides - gentamycin, Polymycin B, neomycin, tobramycin
Quinolones - ciprofloxacin, oloxacin, levofloxacin, moxifloxacin
Macrolide antibiotic - Azithromycin
SP AND IP - all current
38
Inflammatory response and allergy mechanism
1) Response to threat: infection, allergy or trauma
2) Biological response of vasculature
3) ocular structures susceptible to damage
[antigen-antibody]>allergen>IgE >mast cells >histamine
vasodilation, itching, oedema
39
Mechanisms of action, corticosteroids
1) Corticosteroids
- inhibit cyclooxygenase, so decreased prostaglandin
- short term therapy
- eg Hydrocortisone and prednisolone
- AR - raised IOP
- corneal thinning
- betamethazone, dexamethazone, fluromethazone, rimexalone, loteprednol, etabonate, prednisolone
- ONLY SP AND IP AND ALL
2) NSAID
- inhibit prostaglandin synthesis
- diclofenac sodium (AS), the rest all IP AND SP
3) Antihistamines (antagonist),
- Block H-1 histamine receptors
- antazoline EL, Emedastine AS, ALL SP AND IP
Antazoline
- indic, allergic conjunc
- CI <5yrs, cl problems
- AR - transient stinging
- prep - Otrivine-Antistin: 0.5%
4) Mast cell stabilizers,
- Inhibit CA2+ inflow, no degranulation
- loading does req
- Sodium cromoglycate EL
- lodoxamine EL
- nedocromil AS
- ALL SP AND IP
Sodium cromoglycate
- acute allergic conjunc/season
- CI - soft CL, hypersensitivty
- AR - transient stinging
- prep - opticrom
Lodoxamine
- inhibits release of Mast cell mediators
- allergic conjuc
- CI - <4 yrs, CL, hypersensitivity
- AR, burning, itching
- prep -alomide eyedrops 0.1%
5)Vaso constrictors
40
Anti histamines + MSC
No EL
AS
Azelastine Hydrochloride - AS
Ketotifen - AS
Olopatadine - AS
IP AND SP
all available
41
Vasoconstrictors
determine cause of redness
- prolonged use can cause reactive hyperaemia
eg - naphazoline, xylometazoline often
combined with antihistamine
-we have access to all
42
Glaucoma
1 - Beta blockers, decrease aqueous humor production = lower IOP
prostaglandin first choice
CI - asthma, heart/lung disease
Receptor sensitivity - B1 heart, B2 Bronchioles
- Timolol - 12% of all Rx
dorsolamide (Cosopt ®), brimonidine(Combigan ®)
brinzolamide (Azarga ®), latanoprost (Xalacom ®)
travoprost (DuoTrav ®), bimatoprost (Ganfort ®)
tafluprost (Taptiqom ®), Betaxolol, Carteolol,
Levobunolol
2 - Prostaglandin analogues & prostamides
Latanoprost, tafluprost, travoprost, bimatoprost
- AR - eyelash growth, dark lid skin
3 - Sympathomimetics
brimonidine, a2 agonist
apraclonidine, a2 agonist used after surgery
- combined products
- brimonidine & timolol - combigan
- brimonidine & brinzolamide - simbrinza
5 - Carbonic anhydrase inhibitors
Dorzolamide, 3x daily
Brinzolamide, 2x daily, more comfort
Dorzolamide + timolol =cosopt
```
6 -Miotics
- pilocarpine, 1,2,4% drops - muscarinic receptor agonist
drops iop by 15-20%, 3x/4x a day
superseded by newer agents
significant AR
```
43
Role of optom in AR
> Monitor - Large sample, wide age range, regular visits
> Detect - Base line data, quantify OAR, assess to FIT
> Report - Reporting essential, implied criticsm, med continues.
report
- MHRA.GOV.UK
- CONSULT GP INDEPENDANTLY
- MUST INFORM GP
- Black Triangle drugs
- Drugs given, vaccines, OCT, herbal remedies
- areas of interest, children, young and elderly
44
AR - Medical Devices, Sources of information, probability of occurrence
- CL, care products
- ophthalmic equipment
- dressing
- disinfecting, sterilizing equipment
SOURCES OF INFORMATION
> patient - part of GH assessment, name of drug/condition, consult BNF
> local RX - Prescribing profile, cardiovascular/CNS, log book of medicines
> Black triangle drugs
> mims.co.uk
> mhra.gov.uk
> emc.medicines.org.uk
CONDITION - CHRONIC PATHOLOGY METABOLISM - route of administration
PX - AGE, HISTORY, GENETIC - systemic AR
DRUG - NATURE, DOSE, INTERACTIONS
```
AMIODARONE - anti-arrhythmic
- corneal microdepositis
no stain, clear after 3-7 months, change lens
- night glare
- Optic Neuritis, phototoxicity
```
VIGABATRIN - for epilepsy
VF constriction - dose dependant,
Field deficits in CV, CS, VA
CORTICOSTEROIDS - suppression of inflam/allergy
Cataract - PSC, BILATERAL, IRREVERSIBLE
Raised IOP - glaucomatous change
Corneal Oedema
HYDROXYCHLOROQUINE - for rheumatoid arthritis
corneal deposits, bulls eye macular, check peri-macular field
TAMOXIFEN - Post-surgery breast cancer
Retinopathy, keratopathy, cataract
Vortex corneal deposits - amiodarone, chloroquine, tamoxifen, chlorpromazine, indometacin.
45
Auxiliary topics - ocular peri-operative drugs
- Ocular peri-operative drugs - injected into AC at surgery time to prepare.
prevent inflam, pain, prophylaxis
Diclofenac, flurbiprofen: prevent miosis in surgery
cefuroxime: after cataract surgery
1) apraclonidine - alpha 2-adrenoreceptor agonist, reduce IOP via reducing AH prod
2) acetylcholine - instilled into AC in surgery, cause rapid Miosis
3) sodium hylauronate - with salt solution in surgery
4) sodium chloride - 0.9% for surgery irrigation
5) povidone-iodine - antisepsis for conjuc, prevent infection
46
Auxillary topic - Sub-foveal choroidal neovascularisation
- Sub-foveal choroidal neovascularisation
Anti-VEGF
Pegaptanib
Ranibizumab
Aflibercept
- Verteporfin
subfoveal choroidal neovascularisation
activated by local irradiation using non-thermal red light, produces cytotoxins
47
Auxiliary topics - Vitreomacular traction
Vitreomacular traction
- Ocriplasmin
including when associated with a macular hole of
diameter less than or equal to 400 microns.
48
Auxiliary topics - Nutritional supplements
good and bad
robust evidence req for AMD
carotenoids, balanced diet, healthy weight, no smoking
49
Auxiliary topics - drugs for myopia treatment
- pirenzepine
- 7-methylxanthine (‘7-mx’)
- Atropine (CYCLOPLEGIA +MYDRIASIS)
enters muscarinic receptors (cillary muscle) via M3
Inhibits myopia in children action on sclera
50
Intro
AFLUC
EL, AS, SP, IP
Extraocular drugs - Fluorescein, anaesthesia, anti histamines, anti bac, tear subs
Intraocularagents - cycloplegics, miotics, mydriatics
Drug sources - inorganic, organic, synthesis, proteomics & genomics
Nomenclature
1) full chem name
2) brand
3) shorter generic name
51
Administration
```
3 points before admin:
1) Clinical data
2) Why this drug?
3) Indirect consequence of it?
CONSENT
```
Before
Why
What
When
Give leaflet - educating: driving, topical anaesthesia, AR/allergy
Principle concerns
1- Mydriatics - dilation dont drive etc, glare, ACG
2- topical anaesthetic - 15 mins before instillation, 25 mins before CL reinsert
3- AR - ocular/ systemic
```
Administration -
Wash hands and short nails
4D's
DRUG
DOSE
DATE
DISPOSAL
```
Instillation technique order
1) remove CL
2) clear throat
3) head back
4) nose horizontal
5) expose fornix
6) keep looking back
7) instil in fornix
8) release
9) head forward
10) close eyes and wipe
52
Formulation
Process where excipients combines with generic drug to produce a final medicine
-
Examples of excipient
-buffers, chelating agent, viscosity agents and electrolytes, antimicrobial preservatives
Sterility -
Minims: (sterile and single dose)
Multidose containers for preservatives
Preservatives (antimicrobials) - Quaternary ammonium compounds, Benzalkonium Chloride (0.01%), Mercurials (20%), Phenylmercuric nitrate (0.002%), Alcohols (20%), Chlorobutanol, Others
Boric acid, Chlorhexidine (0.01%)
Stability -
Store in cool and dark
Ph vs tonicity
- Cornea is semi permeable membrane,
- Isotonicity is 300 milliosmoles/kg and isotonic to tear film, eye drops change this when applied.
- Tonicity also measured as % of NaCl - 0.9%
- Buffer - sodium acetate, sodium borate
Sustained activity -
Viscous enhancing agent: povidone, hydrophilic CL, ointments, cellulose derivatives
53
Drug preps
```
Minims: 0.5% & 1%
paper strip
multidose container
ointment
gels
lotion
irrigation system
wafer inserts
```
POSOLOGY: the study of the dosages of drugs,
especially the determination of appropriate doses
BD: twice (two times) a day, stands for ‘bis die’
OD: once a day; stands for ‘quaque die’
OD nocte: once a day at night
TDS: three times a day; stands for ‘ter die sumendum’
QDS: four times a day; q.i.d. stands for ‘quater die
sumendum’
54
Pharmakinetics
Action of a drug in your body over a period of time.
Admin + Formulation
- Dosage & instillation (dosage vs conc)
- Drug vehicle - usually sol
- Surface drainage and retention - q of tears
- Vascular absorption
eye drops - 50ul
palpebral capacity - 30ul
Tear layer - 7-10ul
drop life - 2 mins
Corneal transmission
1) FAT - tear layer, corneal epithelium - Bowmans membrane (squamous tight layers)
2) H2O - stroma
3) FAT - descemets membrane (junctional gaps in endothelium cells), corneal endothelium, anterior chamber
1% of drug reaches ac, conc decided based on this.
Biphasic solubility
- corneal epith/endo - allow fats through only (non ionised)
- stroma - allows water soluble and ionised particles through
- AC- allows everything through
Excretion - Intraocular excretion - diffusing into surrounding vessels and into aqueous for canal of schlemm
- oxidation and reduction and hydrolysis happens in liver and kidney excretion
```
Additional factors:
Age - kidney and liver less efficient
Body-weight - low higher doses (children),
higher BMI can store it for longer
Gender - recommended amount subject
genetics - AR
interaction - interact with other meds
pathology - CI, excretion
Time - best with food some
Tolerance - built up
```
55
Legislation
Medicine: is a substance used to
treat or
prevent disease
restoring, correcting or modifying physiological functions
by exerting a pharmacological, immunological or metabolic action; a medicine can also be used to make a medical diagnosis.
Medical Device: diagnosis/prevention/monitoring/treatment of a disease - does not involve pharmacology, immunology, metabolism
56
HMR 2012 enforced & MHRA
HMR 2012 - sets legislation req, for admin, supply and prescription
- Sales and supply through registered pharm
- Medical devices - CE annotation
POM - doctor, dentist or vet
P - from pharmacy
GSL - supply to public without pharm. supervision
- eye drops and eye ointments not
available under GSL
- Certain drugs can be a combination of GSL, P and POM depending on e.g. pack size, %, presentation and use.
- Contact Lens products/solutions & diagnostic dyes are devices
57
AS
non sight threatening conditions
● 2 years post-registration;
● Post-graduate course covering theory and practice of
prescribing;
● Hospital placement under supervision of
ophthalmologist.
58
Signed orders
req for EL AND AS, given by optom to pharmacist or by px if given instruction
```
Content:
optom name address, GOC no
date
px name, address
drug, dose, reason
labelling directions
optom signature
```
59
SP
voluntary relationship with an independent
prescriber (i.e. doctor)
management plan is agreed for an individual patient
SP manage px cond, prescribing and management
60
IP
responsibility of assessment, diagnosis and management
61
Comanagement schemes
- Limited special circumstances
- post surgical
- drugs outside P, EL, AS
- under authority of Patient group direction
- access to responsible medical practitioner
- must be signed by a senior medical doctor and senior pharmacist
62
Self prescribing and treatment
1) Avoid, avoid POM on family/friends, risks litigation due to less objectivity
xexceptions - minor ailments/emergencies
2) no legal restriction on instillation
- but optom still responsible for it, should intervene and be on premises
