28. Oral Medications for Treating the Anterior Eye Flashcards
What are the best practices for prescribing medication? (4 points)
- Select the best drug according to px presentation e.g. where in the eye?
- Ensure max efficacy and least propensity for side effects
- Orals for ocular surrounding tissues
- Use Australian Medicine Handbook as reference
What are the 8 patient factors that need to be considered before prescribing?
- Px age
- Weight
- General health status
- Mental status & potential medications using for mental status
- Allergy Hx
- Liver and kidney function
- Present medications
- Pregnancy status / Use of oral contraceptive pills
What are the age ranges for neonates, infants and children, according to the Australian Medicine Handbook?
- Neonate = 0 - 28 days
- Infant = 1 month - 2 years
- Child = 2 - 12 years
According to AMH, children over the age of ...
are eligible for the same dosage as ...
. Younger px should be assessed for their ....
and ...
using one of the many ...
, such as AMH, MIMs or ...
. It is also essential that optoms ...
with the child’s ...
or ...
.
According to AMH, children over the age of 12
are eligible for the same dosage as adults
. Younger px should be assessed for their suitability
and contraindications
using one of the many reference guides to medicines
, such as AMH, MIMs or Australian Prescriber
. It is also essential that optoms communicate
with the child’s paediatrician
or family GP
.
What are the 5 main classes of oral medications for ophthalmic diseases?
- Antibiotics
- Steroids/ Corticosteroids
- Antivirals
- Analgesics
- Carbonic anhydride inhibitors
What are the 5 classes of antibiotics?
- Penicillin
- Cephalosporin
- Macrolides
- Fluoroquinuolones
- Tetracycline
Penicillins are ...
used in eyecare. They work by inhibiting ...
. Penicillins contain a ...
that allows them to be ...
. However, ...
produce ...
which degrades the clinical efficacy of penicillins. In this case, ...
and ...
can be used.
* ...
[dicloxsig] is resistant to ....
. It also has a short half life, therefore dosage of ...
mg regimen
can be taken without regard to ...
.
* ...
[augmentin] is a classic ...
penicillin. It is combined with a ...
inhibitor, ...
. This combination increases the drug’s spectrum of activity against ...
. This extends coverage of ...
and ...
. It also has excellent choice in combating most common ...
and ...
infections.
- Penicillins are
rarely
used in eyecare. They work by inhibitingbacterial cell wall synthesis
. Penicillins contain abeta-lactam ring
that allows them to bebactericidal
. However,staphyloccal species
producepenicillinase
which degrades the clinical efficacy of penicillins. In this case,dicloxacillin
andamoxycillin
can be used. -
Dicloxacillin
[dicloxsig] is resistant topenicillinase
. It also has a short half life, therefore dosage of250
mgQID
can be taken without regard tomeals
. -
Amoxycillin
[augmentin] is a classicsynthetic
penicillin. It is combined with abeta lactamase
inhibitor,potassium clavulanate
. This combination increases the drug’s spectrum of activity againstbeta lactamase producing bacteria
. This extends coverage ofG+ and G-
. It also has excellent choice in combating most commoneye
andeyelid
infections.
What are the 3 levels of penicillin dosage determined by severity of clinical conditions?
BID for 1 week
* Mild - 500mg
* Moderate - 875mg → most common dosage
* Severe - 1000mg
What are the potential side effects of penicillins? (3 points)
*Hypersensitivity reactions (20%) → Skin rashes (mostly), severe anaphylaxis (uncommon)
* Alter normal flora in respiratory tract
* GIT upset
What are the 3 alternatives to penicillin when one has an allergy to penicillin?
- Cephalosporin
- Macrolide
- Fluoroquinolone
Cephalosporins are an alternative to ...
. The oral type used in optometry is ...
, which is commonly traded as ...
. It is also usually the ...
in ophthalmic antibiotics. It affects bacterial ...
. It contains a ... group
, however it is not affected by ...
like penicillins as this is derived from ...
. Depending on the severity or conditions, cephalosporin is usually prescribed for duration
with dosage of ...
mg regimen
or ...
mg regimen
(2g).
Cephalosporins can destroy ...
necessary for the synthesis of ...
, which can result in ...
, therefore it is contraindicated in ...
.
Common adverse reactions to cephalosporin are similar to penicillin because ...
, where 5-10% of those allergic to penicillin are also ...
. Consequently, px with hx of penicillin anaphylaxis should avoid the use of cephalosporin and choose either ...
or ...
.
Cephalosporins are an alternative to penicillins
. The oral type used in optometry is cephalexin
, which is commonly traded as keflex
. It is also usually the first choice
in ophthalmic antibiotics. It affects bacterial cell wall synthesis
. It contains a beta lactam group
, however it is not affected by penicillinase
like penicillins as this is derived from different amino acids
. Depending on the severity or conditions, cephalosporin is usually prescribed for 1 week
with dosage of 500
mg BID
or 500
mg QID
(2g). Cephalosporins can destroy intestinal bacteria
necessary for the synthesis of vitamin K
, which can result in impaired blood clotting
, therefore it is contraindicated in haemophiliacs
. Common adverse reactions to cephalosporin are similar to penicillin because they share similar structures
, where 5-10% of those allergic to penicillin are also allergic to cephalosporin
. Consequently, px with hx of penicillin anaphylaxis should avoid the use of cephalosporin and choose either macrolide
or fluoroquinolone
.
Fluoroquinolone is a ...
that is usually reserved for use when there is a ...
. Fluoroquinolones inhibit ...
by blocking ...
activity. Examples include drug
which is used by GPs for UTI and drug
dosage
mg regimen
for duration
. This is contraindicated in epilepsy, ...
and ...
.
Fluoroquinolone is a broad spectrum antibiotic
that is usually reserved for use when there is a penicillin allergy
. Fluoroquinolones inhibit bacterial DNA synthesis
by blocking DNA gyrase
activity. Examples include norfloxacin
which is used by GPs for UTI and ciprofloxacin
500
mg QID
for 1 week
. This is contraindicated in epilepsy, myasthenia gravis
and pregnancy
.
How can you differentiate between hordeolum internum, chalazion and pre-septal cellulitlis based on px response?
- Hordeolum internum - pain at the middle of the eyelid
- Chalazion - no pain
- Preseptal cellulitis - pain all over the orbit
Internal hordeolum is an ..., ...
infection that affects the ...
and caused by ...
.
It is managed by ...
and ...
.
There are 3 different treatment options, all are for a treatment period of ...
days:
* Most common = trade name
...
mg regimen
* Augmentin ...
mg regimen
* Dicloxacillin ...
mg regimen
Internal hordeolum is an acute, focal
infection that affects the meibomian glands
and caused by staphylococcus aureus
.
It is managed by hot compresses
and topical therapy
.
There are 3 different treatment options, all are for a treatment period of 7 days
:
* Most common = Keflex
500
mg QID
* Augmentin 875
mg BID
* Dicloxacillin 250
mg QID
Preseptal cellulitis can develop from ...
. It is characterised by the ...
of the eyelid, anterior to the ...
. This should be differentially diagnosed from ...
, which is a more ...
condition. To differentiate, ...
should be conducted. If there is no pain, this indicates ...
. This is different to internal hordeolum as there is no ...
/ ...
.
Preseptal cellulitis is commonly caused by ...
in adults and ...
in children. It also associates with ...
, ...
and upper respiratory tract infections. Preseptal cellulitis should be treated ...
using either drug
..
mg regimen
or drug
...
mg regimen
, usually for 5 to 10 days.
Preseptal cellulitis can develop from internal hordeolum
. It is characterised by the diffuse inflammation
of the eyelid, anterior to the orbital septum
. This should be differentially diagnosed from orbital cellulitis
, which is a more severe
condition. To differentiate, motility
should be conducted. If there is no pain, this indicates preseptal cellulitis
. This is different to internal hordeolum as there is no focal lesion
/ inflammation
. Preseptal cellulitis is commonly caused by staphylococccus spp
in adults and streptococcus pneumoniae
in children. It also associates with sinusitis
, dacryocystitis
and upper respiratory tract infections. Preseptal cellulitis should be treated empirically
using either augmentin 500mg QID
or keflex 500mg QID
, usually for 5 to 10 days.
Acute dacryocystitis is the ...
of the overlying ...
. It is usually associated with obstruction of the ...
. This is commonly caused by ...
or ...
. Px may present with ...
discharge, ...
and pain and swelling over the ...
area. Treatment involves drug
...
mg regimen
for duration
days. If intervention is done in a timely matter, there should be a ...
.
Acute dacryocystitis is the inflammation
of the overlying lacrimal sac
. It is usually associated with obstruction of the nasolacrimal duct
. This is commonly caused by staphylococcus epidermidis
or aureus
. Px may present with mucopurulent
discharge, epiphora
and pain and swelling over the medial canthal
area. Treatment involves Keflex
500
mg QID
for 7
days. If intervention is done in a timely matter, there should be a rapid improvement
.